Abstracts of the 49th annual scientific meeting of the cardiac society of Australia and New Zealand

Abstracts of the 49th annual scientific meeting of the cardiac society of Australia and New Zealand

Heart, Lung and Circulation 2001; 10 (Suppl.): A55-A152 ABSTRACTS OF THE 49TH ANNUAL SCIENTIFIC MEETING OF THE CARDIAC SOCIETY OF AUSTRALIA AND NE...

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Heart, Lung and Circulation 2001; 10 (Suppl.): A55-A152

ABSTRACTS OF THE

49TH ANNUAL SCIENTIFIC MEETING OF

THE CARDIAC SOCIETY OF

AUSTRALIA AND NEW ZEALAND

SUNDAY ~-WEDNESDAY 8 AUGUST AUCKLAND,

NEW ZEALAND

2001

A56

49th Annual

Scientific

Meeting

of CSANZ

Heart,

12 MONTH EVALUATION OF A NURSE INITIATED PHONE SERVICE POST ANGIOPLASTY. J.Crilly*, MDahl. tigations Unit, The Prince Charles Hospital, Brisbane Australia.

FOLLOW UP Cardiac Inves-

Decreased lengths of hospital stay increases the complexity of patient discharge needs. This causes major challenges for nurses today, such as providing complete, effective pre-discharge education and support. Recent literature demonstrates that follow up phone services provide ongoing care and support to patients and their families after discharge. The Cardiac Investigations Unit at The Prince Charles Hospital is a special&d cardiac unit that has a unique Angioplasty Nursing Service. The service consists of a clinical nurse specialist who educates and supports Angioplasty patients during their hospital admission. Post discharge the Angioplasty Service provides telephone follow up. Patients are contacted at 1, 6 and 12 months after their procedure. A small example of data evaluated is shown below Month

No. of pts contacted

% of haematomas

% of better quality of life

Jan

38 234 90 129 153

10.53 3 6.6 4 0.65

85 88 84 89 93

Feb Mar *pr May

% of return of angina 42 27 28 44 34

% of return to smoking 0 3.4 0 4 4

The data collected demonstrates and supports other findings that phone follow-up for patients after hospital discharge has potential for port and increased patient and family satisfaction with health care. follow-up service assists with reinforcing pi-e-discharge education and factor modification post Angioplasty.

telesupThe risk

Lung

and Circulation

LONG-TERM GAINS FROM A COMPREHENSIVE SYSTEM FOR HEART FAILURE e H. Krum -A.. (HFC), The Alfred Hospital. Melbourne, Victoria

2001; 10

MANAGEMENT Heart

Failure

Background: Multidisciplinary treatment of congestive heart failure (CHF) can provide significant short-term benefit. We have previously demonstrated an 82% reduction in hospital admissions at 6 months following a comprehensive management program (CMI’). Longer term benefits remain uncertain. Methods: Eligible patients (pts) were NYHA Class 3 or 4 CHF, LVEF ~40 % and receiving stable outpatient therapy. CMP comprised cardiology assessment and follow up, intensive education and referral to a tailored exercise program for a three-month period. Patients were then given a home exercise program, advice on patient initiated diuretic use and 3 monthly Heart Failure Centre reviews. Pt. outcomes were assessed at 6 months and 24 months post recruitment. Results: 24/36 pts have to date been followed-up at 2 years, (2 pts transplanted, I pt. died). Sustained benefit was seen in all measures, including admissions, NYHA Class, exercise caaacitv, beta blocker use and OOL.

Admissions/pt.* Zero admissions NYHA Class QQL (Total score) # 6 minute walk (m) beta-Blocker use l

6 months pre-enrolment

Baseline n=21 Mean * SE 0.71 +_0.18 33% 3.04 f 0.04 50 * 5.5 442 + 15.6 39%

2years n=21 Mean f SE 0.14 * 0.10 90% 1.85 f 0.14 35 * 5.5 514k28 84%

p value

p=O.Ol p
vs. 2 years post enrolment

#Minnesota Living with Heart Failure Questionnaire Conclusion: Persistent benefit to 24 months has been demonstrated short term comprehensive management program for advanced heart This underscores the significant health benefits of such approaches.

THE 6F ANGIOSEALTM DEVICE FOR VASCULAR ACCESS SITE HAEMOSTASIS AFTER PERCUTANEOUS CORONARY INTERVENTION. EJ David, FL See*, SG Worthley, RW Harper, IT Meredith. Cardiac Catheterisation and Interventional Laboratory and Cardiovascular Research Centre, Monash University, Monash Medical Centre, Melbourne. Peripheral arterial access site haemostasis after percutaneous coronary intervention (PCI), is an important cause of morbidity, with haematomas and false aneurysms leading to increased hospital stay, expense, patient discomfort and occasionally requires surgical repair. Thus, the ability to achieve rapidly and easily haemostasis post PC1 may lead to earlier mobilisation of the patient, and allow the early institution of potent anti-platelet regimes (such as IIb/IIIa inhibitors) as appropriate. We report our preliminary experience with the new 6Fr AngiosealTM device for this purpose. The in-hospital and one-week vascular outcomes following closure of vascular access sites using the new 6F AngiosealTM device following PC1 at a single institution were analysed from July 2000 to February 2001. Patient demographics, initial success in obtaining haemostasis, time required for device insertion, and 24 hour and 7 day follow-up of vascular access site complications were recorded. Demographic data is presented as mean&D, and insertion time data as mean&EM. Thirty seven patients (28 male and 7 female, age 63.5k12.5 years) underwent 6F Angiosealm device insertion for vascular access site closure (32 right femoral artery, 3 left femoral artery and 2 right brachial artery) after PCI. Twenty two patients (59%) had a previous arterial puncture within the past 12 months at the same site as the device was deployed. The 6F AngiosealTM device was successfully deployed in all 37 cases and instant haemostasis obtained in 36 of these (97%). The deployment time was 2.32+ 0.28mins. Three patients (8%) were receiving either abciximab or tirofiban and there were no adverse outcomes in these patients. At 24 hours, only one patient (3%) had a haematoma greater than 5 cm, one patient (3%) had a false aneurysm (successfully treated with ultrasound guided external compression) and two patients (5%) had required the use of a femostop device overnight for access site oozing. At 1 week all complications had resolved, although a 5 to 1Ocm haematoma remained in the patient with a haematoma at 24 hours. Early experience with the 6F Angioseal rM device in PC1 suggests that it is a rapid and effective means of achieving arterial access site haemostasis

Centre

with a failure.

IS TRANSIENT SYSTOLIC HYPOTENSION DURING ACCELERATED ADMINISTRATION OF STREPTOKINASE ASSOCIATED WITH REDUCED TIME TO ST-SEGMENT RESOLUTION? Valeimidi N*. Brings JM. tm. Coronary Care Unit, The Queen Elizabeth Hospital, Adelaide, South Australia. tSchoo1 of Nursing and Midwifery, University of South Australia, Adelaide, South Australia. Background: For patients with acute myocardial infarction (AMI), a reduction of 2 50% ST-segment elevation has been associated with reperfusion. Other indicators of reperfusion include reduction of chest pain, ventricular arrhythmias and possibly, transient systolic hypotension during thrombolytic therapy. Method: We examined data for 33 consecutive patients treated with accelerated streptokmase (1.5 million units over 30 minutes) for incidence of transient systolic hypotension (<90mm hg) during thrombolytic administration. Blood pressure was measured 5-minutely and more frequently if symptomatically indicated. We measured time from thrombolytic commencement to 2 50% resolution of ST-segment elevation using continuous ST-segment monitoring. Non-paired t-test was used to compare time to reperfusion for groups with and without transient hypotension. Results: 21 patients (64%) experienced transient systolic hypotension during thrombolytic administration. The mean time from commencement of thrombolytic therapy to 250% reduction of ST-segment elevation is demonstrated in the table below:

Mean time to 250% ST resolution (mm)

All patients (n=33) 62.3

Transient (n=21) 57.9

No hypotension (n=12) 69.8

Conclusion: Transient systolic hypotension during accelerated streptokiiase administration occurs in around two thirds of patients. There is no significant difference in time to ST-segment reduction in patients with or without transient hypotension during thrombolytic adminstration.

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CLASSIFICATION OF DIASTOLIC FILLING PAI-IERN: COMPARISON OF 3 PRELOAD REDUCTION TECHNIQUES WITH CONTRAST ENHANCED PULMONARY VENOUS DOPPLER. HI Walsh*. GA Whalleu, G Orsboum. CD Gamble. N Sharoe. RN Dourrht]L University of Auckland, NZ.

NURSES’ PERCEPTIONS OF QUALITY NURSING CARE PROVIDED TO POST PROCEDURE ELECTIVE PERCUTANEOUS TRANSLUMINAL CORONARY ANGIOPLASTY PATIENTS S.R. Clearv’, S.B. Walker. S. Tiroiwong. The Prince Charles Hospital Brisbane and Central Queensland University

Diastolic filling is often measured by echo using mitral valve Doppler (MVD) and pulmonary venous Doppler (PVD). Trans-oesophageal (TOE) PVD differentiates normal from pseudonormal filling, but transthoracic (TIE) PVD is not as reliable. Contrast enhanced TTE-PVD provides similar results to TOE-PVD. Preload reduction can also differentiate between diastolic filling phases and can be achieved through Valsalva maneuver (VAL) or sublingual glycetyl trinitrate (GTN). The aim of this study was to compare preload reduction by 3 methods to MVD and PVD with contrast, for the evaluation of diastolic filling. Methods: In 19 subjects (9 normal, 10 CHF) MVD and I’VD were obtained from the apical 4-chamber view. PVD was obtained during an infusion of Levovist (4g, IV). MVD was compared using the 3 preload reduction methods, GTN, VAL, quantified Valsalva (QVAL), subjects blowing against a sphygmomanometer, Diastolic filling was determined by E:A ratio, deceleration time (DT), A wave duration, PVD atria1 reversal and the change in E:A ratio with preload reduction. Results: E:A ratio was equally reduced by all methods, while DT was increased in VAL and QVAL but not GTN (p>O.O5).

This qualitative grounded theory study conducted in a large Queensland Metropolitan Hospital, explored and described nurses’ perceptions of quality and factors that affect quality nursing care provided to Percutaneous Transluminal Coronary Angioplasty (PTCA) patients. Data for this study was gathered from tape recorded focus group interviews, participant observation, in-depth interview and published literature. A total of 35 Registered Nurses participated in the study from two settings that provided care for the elective PTCA patient, a Cardiac Investigation Unit and a Coronary Care Unit. The process of data collection, analysis and theory formulation occurred using a constant comparative approach. Quality nursing care was described as the combination of basic, personal and application standards. The nurses believed that quality nursing care was achieved in the relationship with the PTCA patient when a marriage of expectations occurred. The factors identified that affected the provision of quality nursing care for elective PTCA patients, were subsumed into three categories, structure, process and cultural factors. The impact of these factors on the provision of quality nursing care for PTCA patients were examined and presented. Utilising the results of this study recommendations are made for future care of the PTCA patient, utilising the theory of quality nursing care that emerged from discussions with nurses who participated in this study Acknowledged are the factors that affect quality nursing care provided for this group of patients. The results of this study will help challenge the existing nursing practice of caring for elective PTCA patients.

Methods MVD VAL

EEA 1.16 (2 0.85’(+ 0.85yt 0.93+

DT 0.60) 0.44) 0.43) 0.48)

AEA

ADT

195.2 (t5t3.3) 241.4+ (?67.2) 247.1’ (t60.7)

-0.31 (t 0 42) -0.31 (2 0.39) QVAL -0.23 (+ 0.25) GTN 215.4 (r 59.7) *D ~0.005, cornDared to MVD, +P <0.05, compared to MVD

47.7 (ai.5) 51.9 (2 81.8) 20.2 (i’ 64.4)

The classification

reduction:

MVD

of filling p attem . was improved Diastolic Filling Pattern 0 1 2

8 MVD+PVD 6 VAL 5 QVAL 6 GTN 5 (O=nonnal, l=abnormal

with

pre-load 3

8 R 2 8 3 3 8 2 3 8 3 2 relax”, 2=pseudonormal, 3=reversible r&r”,

4 3 3 0 0 1 4=restr”)

Conclusion: Preload reduction by either Valsalva maneuver or GTN is equally diagnostic for evaluation of diastolic filling, and is superior to PVD in that it provides information for the assessment of restrictive filling patterns.

EMERGENCY RE-STERNOTOMY: A QUALITY ACTIVITY M.Fereuson. Cardiac Surgical Intensive Care Unit (CSICU). Charles Hospital (TPCH), Brisbane, Australia

N. Burns+, The Prince

TPCH is a 500-bed tertiary referral hospital whose specialities include adult & paediatric Cardiac Surgery. A large caseload of over 2205 open and closed cardiac surgical procedures per year necessitated the streamlining of re-sternotomy events within the CSICU. This presentation discusses a mutli-disciplinary, problem-solving approach to emergency re-stemotomy and includes a description of, and indications for the procedure. It describes the processes implemented to ensure nursing and medical personnel have the relevant knowledge and skills to provide an optimal service in the event of such an emergency. Strategies were developed utilising a quality activity framework that concentrated on the individual needs of medical, nursing and peri-operative staff. Areas such as disorganisation, duplication of roles and patient outcomes were assessed using a collaborative team approach. Following the introduction of structured, role-specific guidelines and an intense training program which included several simulated re-opens, there was a demonstrated improvement in organisation, patient safety, professional practice and an overall reduction of stress within the multi-disciplinary team.

RESTRUCTURING OF A CARDIAC INVESTIGATION UNIT. THE IMPLICATIONS OF ORGANISATIONAL CHANGE M. Dahl. S. Clearv. K. Constantinou. A. Shields* Cardiac Investigation Unit, The Prince Charles Hospital. Restructuring of Cardiac Investigation Unit at The Prince Charles Hospital occurred over a period of four years. Relocation to a new facility at The Prince Charles Hospital campus resulted in the amalgamation of eight geographically detached departments each with their own management and organisational culture into one cardiac investigation unit. The departments affected by this change included: two cardiac catheter laboratories and attached patient reception area and equipment storage, one electrophysiology laboratory and attached patient reception area and equipment storage, data viewing and image archive storage area, a cardiac medical ward, ECG department, pacemaker clinic, trans-telephonic pacemaker clinic, procedural admission department, exercise stress laboratory, echocardiography, medical imaging, and clerical administration including booking office. The professional personnel represented from these departments included medical officers, nurses, radiographers, cardiac scientists and technicians, administration officers, and operational services personnel. Prior to amalgamation each of these professional groups operated autonomously, therefore, human resource management in the integrated unit became a paramount issue. This paper will discuss the change strategies implemented, impact on human resource management and evaluation of outcomes. Evaluation of this process identified the strengths and the weaknesses of the strategies implemented. Recommendations proposed will assist managers who are or will be involved in organisational change.

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49th Annual

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FAMILY HISTORY OF PREMATURE ASSOCIATED WITH SIGNIFICANTLY CIUM SCORE IN ASYMPTOMATIC Q, SA.

of CSANZ

CORONARY HEART DISEASE IS ELEVATED CORONARY CALSUBJECTS. J Kosiol. B ModraZ. Ashford Heart Scan, Ashford,

The relationship between a family history (FHx) of premature coronary heart disease (CHD) in first degree relatives aged <6Oyrs and a coronary calcium score (CCS) is not clearly defined. This study was undertaken to investigate this relationship in 672 sequential self referred asymptomatic subjects (62%M), aged 35-75yrs, between July and December 2000. Coronary calcium score was measured by the method of Agatston using spiral CT scanning. Demographic data were obtained by questionnaire. Of 180 M and 112 F with a positive FHx, 70 M (39%) and 39 F (35%) had CCS >75th percentile ( matched for age and gender); of 239 M and 141 F with a negative FHx,l6 M (7%) and 8 F (6%) had a CCS >75th percentile. For both M and F, positive FHx was significantly related to CCS >75th percentile (p75th percentile).

Heart,

DOES ALTERATION IN PIXEL SIZE MYOCARDIAL IMAGING ESTIMATION VELOCITY? C A ology, Westmead Hospital, Sydney.

Lung

and Circulation

2001; 10

IMPROVE COLOUR DOPPLER OF ATRIAL CONTRACTION Department of Cardi-

Colour Doppler Myocardial Imaging (CDMI) has traditionally been used to evaluate ventricular contractility using 9x9 pixel sampling. CDMI has not been used to evaluate the atrium, which is a thinner walled structure. We hypothesized that due to the thinner walled nature of the atria 1x1 pixel sampling would be more sensitive to changes in velocities of atria1 contraction. Method: A total of 31 normal, healthy volunteers (mean age 39 + 12 years) had transthoracic echocardiograms (TIE). Using CDMI, mean peak velocities of atria1 contraction in late diastole (A-wave) were measured in apical 4 chamber and 2 chamber views, ensuring a frame rate 2 90 fps. The measurements were taken from the annular, mid and superior segments of the lateral and septal walls of the left and right atrium using 9x9 pixel and 1x1 pixel sampling averaged over two cardiac cycles. Results: Data are expressed as mean + SD. Paired t-tests were used to assess statistical significance. The mean peak velocities were highest in the annular segments. 1x1 pixel sampling resulted in velocities that were consistently higher than 9x9 pixel sampling, however this did not show a uniformly significant difference. Right Atrium Sephml4C Left Atrium 4c km/s) blk.) 4c (cm/s) 9x9 1x1 9x9 1X1 9x9 1x1 Annular-8.3+2.4 -8.4k2.6 -6.7+1.6 -6.8kl.6 -6.3i2.2 -6.6k2.1 Mid -4.5* 1.7 -4.8k2.1 -4.7* 1.6-4.9 r 1.5* -6.3k2.0 -6.4t2.0 Superior-l.4 f 0.9 -1.5 * 1.1 -0.9~0.7-1.0*1.1

Left Atrium 2c b/s) 9x9 1X1 -6.2k2.1 -6.3t2.5 -5.8+2.2 -5.9 k2.5 -0.9+0.8-1.1r0.9*

* p
Conclusion: The results of this preliminary study indicate that CDMI of the atria1 wall may be used to quantify atria1 contraction. Reduction of sampling area showed no consistent significant difference in a normal population. Larger numbers and the significance in diseased states need to be further evaluated. SHARED CARE ANGIOPLASTY PROGRAM (SCAP) IN MELBOURNE STRENGTHENING THE LINKS BETWEEN ASPECTS OF CARE. A B Sculthorpe, Centre for Health Program Evaluation, University of Melbourne; NThurston’.., Epworth Hospital, T McNeair, M Lancaster, Inner Eastern Melbourne Division of General Practice, S Bunker, National Heart Foundation - Victoria, D Sommers, Medibank Private, S lohnson, Merck Sharp & Dohme: Melbourne, Australia. Objectives: To provide more active management for patients who have had coronary stent or angioplasty (PTCA). To improve General Practitioner (GP) follow-up and management of these patients. Method: Patients had undergone a PTCA/Stent at Epworth Hospital in Melbourne. Participating GPs had patients who had undergone a PTCA/Stent and who resided within the postcodes of Inner Eastern Melbourne Division of General Practice (IEMDGP). The program involved intervention at both the patient and GP level. Patients were encouraged to attend a hospital based cardiac education delivered by a cardiac nurse and other health professionals, and were given a patient-held record to improve recording of cardiac risk factors. GPs received a comprehensive discharge summary and were visited by an academic detailer after their patients were discharged from hospital. A cardiac manual was provided to GPs and reminder faxes were sent every 3 months to remind GPs of the need to review their patients. Patient demographic and outcome data was collected from the treating GP and hospital. Twelve-month follow-up data was obtained via a patient record audit and GP interview. This approach assessed patient risk factors 12 months post procedure, and GP response to program delivery and content. Results: Seventy-two GPs were involved in the program over a 12 month period representing 91 PTCA/Stent patients. Interim evaluation indicates the use of a patient held cardiac record as a successful management tool. Patients presented to their GPs on average 12 times within one year of discharge from hospital. GPs exhibit some reluctance to utilise recall systems in this population. Changes in patients’ cardiac risk factors will be presented. Conclusion: Preliminary data suggests the delivery structure and content were well received by General Practitioners. The frequency of visits to GPs highlights the importance of their role with these patients. Further analysis of the data will provide information regarding the impact on cardiac risk factors.

LONG-TERM FOLLOW UP AFTER THE STAR PROCEDURE: AN INTRAOPERATIVE RADIOFREQUENCY ABLATION PROCEDURE FOR ATRIAL FIBRILLATION. 3 C B d* D , e. N Departments of Cardiology and Cardiothoracic Surgery, Westmead Hospital. Sydney The long-term effects on symptoms and medication usage of a novel surgical procedure (Star procedure) were studied. The Star procedure utilizes a radial pattern of radiofrequency endocardial lesions to prevent recurrence of atria1 fibrillation (AF). Method: The Star procedure was performed on 31 patients from 07/95 to 06/00. The patients had paroxysmal or chronic AF of duration 0.3-120 months, refractory to antiarrhythmic therapy. A telephone questionnaire was used to assess symptoms, medications and perceived success of the Star procedure. Results: 76% of the patients responded to the questionnaire with a mean follow up of 3.1 t 1.5 years. 77% of the surveyed patients reported that they felt the procedure had been successful. The Star procedure significantly reduced symptoms of palpitations, shortness of breath and feeling faint on exertion, as well as the need for antiarrhythmic medications. Of the patients with recurrent symptoms the severity and frequency generally decreased following the procedure. There was a significant increase in the use of aspirin post operatively, however this can be explained by 45% of patients changing from warfarm to aspirin following the Star procedure. Pre-star Post-Star -value Palpitahons Shortness of breath Chest pain Faint on exertion Antiarrhythmics Aspirin Warfarin

86% 64% 14% 36% 77% 9% 50%

50% 32% 5% 5% 32% 41% 32%


Conclusion: The Star procedure reduced symptoms and antiarrhythmic usage during long-term follow up in patients with previously refractory

drug AF.

Heart,

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IMPLEMENTION OF A COMPREHENSIVE SERVICE FOR ELDERLY HEART FAILURE PATIENTS. Davidson PM. Paul1 G’. Webster I. Rees DM. The St George Hospital, Gray Street, Sydney

HIGH RATE PACING PERCURS FOR GENERATOR M Ilton, C Sinsleton. W Heddle Cardiology Catheter Private Hospital, Adelaide, South Australia

High rates of readmission and burden of disease challenge health care systems to deliver systematic, structured programs to elderly patients with heart failure. The heterogenous nature of the aetiology, presentation and management of this syndrome dictate a multifaceted approach to care of the elderly patient. The St George Hospital has implemented a tailored, multidisciplinary heart failure service based upon systematic assessment of needs, functional status and ability to self-care. The heart failure service has four discrete foci. These me: . secondary prevention cardiac rehabilitation services l heart failure specific cardiac rehabilitation program for symptomatic patients l home based heart failure management . collaborative palliative care These multidisciplinary programs with flexible entry points strive to create a link between the hospital and community to improve quality of life, optimise health-related outcomes and to ensure a dignified and compassionate death at the end of life. To date 264 patients have been enrolled in heart failure specific programs (61% male, median age 76 years) These programs have demonstrated a decrease in readmission rates in specific heart failure populations and have been favourably evaluated by patients, their families and clinicians. Conclusions: The heterogeneous nature of the elderly heart failure patient requires a collaborative, multifaceted strategy dependent upon assessment of patient needs, functional status and ability to self-care. The St George experience reflects the need for an eclectic approach in the extrapolation of results of randomised controlled trials to clinical practice in order to achieve optimal patient outcomes.

Followup guidelines of the “Hazard Alert” notification, concerning Teletronits Tempo Single and Dual chamber pacemakers resulted in replacement of twenty three Tempo pacemakers over a period of nine months because of their pacing parameters.

WHEN AND IN WHOM DOES VASOVAGAL, BLEEDING AND HYPOTENSION OCCUR IN PATIENTS AFTER PERCUTANEOUS TRANSLUMINAL CORONARY ANGIOPLASTY AND STENT INSERTION? K 1 Daws*, M Richardson, K Sellick. Cardiothoracic Care Centre, St. Vincent’s Hospital, Melbourne and La Trobe University, Melbourne. Vasovagal, bleeding at the vascular access site and hypotension the early stages after percutaneous transluminal coronary (PTCA) and stent insertion.

can occur in angioplasty

The study sought to determine the incidence and timing of vasovagal, bleeding at the vascular access site and hypotension in the immediate post PTCA period. A second aim was to determine whether any patient characteristic or peri procedural feature was associated with the occurrence of these complications. A prospective descriptive study was conducted between 6 September and 21 December, 1999. Data were collected on 205 consecutive patients who had PTCA and/or stent insertion. The incidence and timing of complications were recorded as were patient characteristics and peri procedural features. Data were analysed using Chi square and t tests to determine whether relationships existed. Vasovagal occurred in 18.5%, bleeding in 37.6% and hypotension in 8.8% of patients. No single feature was associated with the occurrence of vasovagal. Low body weight, low platelets and longer pressure times during sheath removal were associated with the occurrence of bleeding (p < .05). The length of time that the sheath remained in situ and vasovagal were associated with the occurrence of hypotension (p < .05).

FAILURE Laboratory,

L Devitt’. Flinders

During explant it was noted that a number of generators were pacing inappropriately at their upper rate. Information was gathered to support this by the clinical records and a additional data sheet consisting of a twelve lead ECG, print outs from the interrogation of the implanted generator and lead analysis prior to explant and then determination of the underlying rhythm. The results from the collection data sheet were as follows. Upper rate

Not able to

Temporary

L Magnet

pacing

interrogate

wire

rate

t Cell impedance

Lead replaced

17 (73%)

3 (13%)

coverage 10 (43%)

4 (17%)

2 (8.6%)

5 (21”h)

Conclusion: The findings of a ‘Tempo’ pacemaker inappropriately is a common marker of impending

pacing at its set upper generator failure.

rate

FREQUENCY AND CLINICAL SIGNIFICANCE OF T-WAVE FLUCTUATION IMMEDIATELY FOLLOWING PERCUTANEOUS TRANSLUMINAL CORONARY ANGIOPLASTY. South K* fKucia AM, tiHorowitz ID, Coronary Care Unit, The Queen Elizabeth Hospital, Adelaide, South Australia. $ University of South Australia, Adelaide, South Australia. $$University of Adelaide, Adelaide, South Australia. Background: Acute coronary syndromes are commonly associated with ST-segment (STs) and T-wave (Tw) changes on the 12-lead electrocardiograph (ECG). The relationship between STs and Tw changes following percutaneous transluminal coronary angioplasty (PTCA) is less clear. Furthermore, patients (pts) undergoing PTCA are heterogeneous with regard to emergency or elective indication for the procedure, which may influence ECG changes post procedure. Method: We examined data for 188 consecutive pts undergoing PTCA over a 12 month period to (1) determine frequency of Tw change and extent of correlation of Tw change with STs change; and (2) determine the longer-term implications of Tw changes on 6 month readmission for angiographically demonstrated stenosis/obstruction of the index artery. All pts had routine continuous 12-lead STs and Tw monitoring for 2 6 hours post PTCA using the GE Marquette ST Guard STs trends were assessed for significant STs changes ( >lmm STs change in 2 contiguous target artery-related leads or 2 2mm STs change in a single target artery-related lead) and/or Tw changes (change in polarity of proximal, peak or terminal Tw and/or >lmm peak Tw change in 2 contiguous target artery-related leads). Results: 151 pts (80%) had Tw changes and 25 pts (13%) had Sts changes post procedure. There was a strong correlation between STs and Tw changes (x2 169.8; p
P value

0.05 0.09

Elective admission for PTCA was a predictor of absence of T-wave changes post PTCA when compared with non-elective PTCA (~~0.05). Conclusions: Tw fluctuation post PTCA is common. There is a strong correlation between STs and Tw change. Absence of Tw fluctuation post PTCA is associated with a good outcome, which may suggest a biological basis for

restenosis minor)

foreshadowed

ischaemic

components.

by processes

which

include

early

(but

usually

A60

49th Annual

Scientific

A NURSING AUDIT HIGHLIGHTS PROMPTING A CHANGE IN K Daws*. N Woollev, Cardiothoracic Melbourne.

Meeting

of CSANZ

Heart,

A HIGH RATE OF VASOVAGAL SHEATH REMOVAL PROTOCOL. Care Centre, St. Vincent’s Hospital,

Symptomatic bradycardia or vasovagal is a potential complication in patients who have had percutaneous transluminal coronary angioplasty (PTCA) and stent insertion. A recent study reported an 18.5% (38/205) incidence of vasovagal at a large metropolitan hospital in this patient group. Vasovagal occurred, in all but one case, while the sheath was in situ or being removed. When data were analysed no single demographic, procedural or post procedural feature was found to be associated with the occurrence of vasovagal. Of note none of the patients who had their sheaths removed after 12 hours experienced vasovagal however low numbers in this group precluded statistical analysis. The high number of vasovagals prompted a change in the sheath removal protocol from pre-medication with morphine to pre-medication with midazolam and the use of local anaesthetic. A follow up audit revealed a reduction in the incidence of vasovagal to 3% (3/100) (p < ,001). This study process highlights the importance of the routine nursing practical and effective research tool. A significant improvement experience of PTCA and stent insertion was achieved.

audit as a in patient

THE SOUTH AUSTRALIAN EXPERIENCE IN DEVELOPING THE OF NURSE PRACTITIONER IN THE MANAGEMENT OF HEART URE J. S Dunne”, Cardiac Services, Flinders Medical Centre, Adelaide, Australia, Australia This paper shall describe the implementation ject in the setting of heart failure and cardiac

of the Extended transplantation.

Practice

ROLE FAILSouth

Role Pro-

As a result of the release of the Nurse Practitioner Project Report in South Australia, Flinders Medical Centre implemented several positions to develop the role of the nurse practitioner in the hospital setting including heart failure/cardiac transplantation. The role of nurse practitioner formalises and expands on what many nurses are already doing. The project involves extending knowledge and skills via a structured and individualised education program and implementing these skills into the clinical setting. The project has both a clinical and university component designed to complement each other. New knowledge and skills were acquired and varied. This paper will describe both the position, the problems and barriers to practical advice for those looking to follow

and sources of support were wide the role and the implementation of implementation and provide some a similar path.

Implementing the Extended Practice Role has been both a challenging and rewarding experience. The project has been successful in enhancing the multidisciplinary services provided to patients with heart failure or who have undergone cardiac transplantation.

HOME HEALTH CARE S Muncaster* R Doueht~ land, New Zealand

Lung

FOR HEART FAILURE: Department of Medicine,

and Circulation

A CRITICAL The University

2001; 10

REVIEW of Auck-

Hospital care for heart failure (HF) accounts for approximately 1 to 1.5% of the total annual health budget. The spiralling cost of HF care has lead to the investigation of interventions to reduce hospital admissions for HE One focus of these interventions has been home health care. Objectives. The purpose of this literature critique was to review home health care in relation to patients with HF. Currently there is a move to increase care in the community and away from secondary care. The aim was to determine the impact of home health care interventions on the New Zealand health care system. Method. Comprehensive searches were conducted through the internet, local libraries and primary sources identified from reference lists. The literature was critiqued systematically and clustered according to type of research and topic. Outcomes. The delivery of care to high-risk patients within the home was seen as beneficial in the six randomised-controlled trials and seven non-randomised trials critiqued. Home care interventions improved quality of life for high-risk patients with HF and reduce the usage of hospital inpatient services for this group. The studies involved differing components of care, in general delivered by a multidisciplinary team. However, common themes emerge from these studies. In particular, the HF nurse practitioner appears important for such programmes. The HF nurse practitioner provides information and education about the physiology of HF, symptom control, medication, and life style modification. These studies have been conducted outside New Zealand thus the adaptation of this approach to the New Zealand health care system needs to be considered prior to the implementation in New Zealand. Consideration needs to be given to cultural diversity and rural isolation within New Zealand. Community consultation would be required to meet the mandates of the District Health Boards (DHB) to provide health services that reflect the needs found within the DHB catchment area. Prior to the establishment of the nurse specialist role clinical and care pathways need to be developed along with the degree of autonomy the nurse would have and the legal implications of managing care and adjusting medications. Conclusions. Multidisciplinary home health care has been proven to reduce hospital&&m for high-risk patients, but more knowledge is required regarding such interventions for the general HF population in the New Zealand setting.

NURSE OPERATOR EXPERIENCE WITH THE 6F PERCLOSE CLOSERm DEVICE TO ACHIEVE FEMORAL ARTERY HAEMOSTASIS FOLLOWING PERCUTANEOUS CORONARY INTERVENTION (PCI). P.L. See*, LT. Meredith. Cardiac Catheterisation and Interventional Cardiology Laboratory, Monash Medical Centre, Melbourne, Australia. Haemostatic closure devices are increasingly used to close femoral arterial puncture following XI. This study assessed the immediate and short term vascular outcomes of 56 patients using the 6F l’erclose CloserTM device by a nurse operator following PC1 (35 patients, 63%) or cardiac catheterisation (21 patients, 37%) between August 2000 and February 2001. A single nurse operator performed all procedures (PLS) under the supervision of a cardiologist (ITM or SGW). Deployment times are presented as mean * SEM. Results: The 56 patients comprised of 34 males and 22 females, mean age 62 years, range 31 to 90 years following closure of 56 femoral access sites (50 right, 61eft). Twenty six patients (46%) had previous ipsilateral femoral arterial punctures or a previous closure device. Five patients (9%) had difficult punctures. The 6F CloserTM device was successfully deployed in 54 cases (96%) and 2 (4%) were unsuccessful (1 patient had excessive scarring around the access site due to multiple previous punctures and deployment had to be aborted and 1 had partial suture capture). The mean deployment time was 7.3 + 0.3lmins. The 6F CloseP device was used to close 6F arterial puncture in 47 cases (84%) and 7F arterial puncture in 9 cases (16%). Seven patients (8%) were receiving either Reopro or Tirofiban. In the cases where haemostasis was achieved (54 cases), this was instant in 46 cases (85%) and 5 to 15 mins. of digital pressure was required in 8 cases (15%). At 24 hours: Seven patients (13%) had a small haematoma (<5cm) and 5 patients (9%) had groin tenderness or discomfort. There were no false aneurysms or large haematomas. No patient required blood transfusion. There were no reported cases of infection. At 1 week: Four patients (7%) had a small haematoma and 1 (2%) patient reported mild groin discomfort. Conclusion: The 6 F CloserTM device can be deployed safely and effectively by a nurse operator provided adequate training and supervision are available. Nurse operator results are comparable to those achieved by multiple operators in a busy catheter laboratory environment.

Heart, Lung and Circulation

49th Annual Scientific Meeting of CSANZ

2001; 10

Afj1

EXPERIENCE OF TRANSPORT OF A PATIENT WITH INTRA-AORTIC BALLOON PUMP (IABP) BY HELICOPTER AMBULANCE FROM A PERIPHERAL HOSPITAL WITHOUT ONSITE SURGICAL FACILITIES. B Williamson*. G Szto. P Gould. J Bladen. W Dvble. K D’Orsa. S Best Frankston Hospital, Frankston, Victoria.

IMPROVED OUTCOMES IN CABG SURGERY WITH PREOPERATIVE COENZYME Q,, THERAPY: A RANDOMISED, DOUBLE-BLIND PLACEBO CONTROLLED TRIAL W. Lyon:, S. Marasco. S. Pete. M. Wowk, F. Sheeran, R. On, I.A. Smith, A. Pick, M. Rabinov. B.B. Davis. D. Esmore. EL. Rosenfeldt. Cardiac Surgical Research Unit, Alfred Hospital b Baker Medical Research Institute, Melbourne

Background: Frankston hospital is approximately 30 minutes by road ambulance to the nearest facility witb on site cardiac surgical facilities. At the time of this experience the cath lab. at Frankstoe was only offering the

is an integral component of cellular Introduction: &enzyme Qis (CoQ,,) membranes, essential for antioxidant function and mitochondrial energy production. Aims: To test whether CoQ,s therapy given prior to CABG surgery: 1) Increases CoQ,, content in atria1 trabeculae and mitochondria; 2) Improves mitochondrial respiration; 3) Protects the myocardium against post-hypoxic contractile dysfunction; 4) Attenuates intra-operative myocardial injury. Methods: 124 patients were randomised to receive either CoQi, (3OOmg/day) or placebo orally for at least 7 days prior to elective surgery. Trabeculae were excised and mitochondria were isolated from discarded right atria1 appendages. Biochemical and clinical parameters were measured postoperatively. Results: Compared to placebo, CoQia therapy increased CoQ,, content of atria1 trabecnlae (21+4 vs 40~5 pg/g w.w., p=O.OOOl) and isolated mitochondria (5.7kO.8 vs 11.2*0.9pg CoQ,s/mg protein, p=O.O002). Mitochondrial respiration was more efficient after CoQis pretreatment (ADFO, placebo vs CoQ,,: 2.920.4 vs 4.2-t0.2, p=O.Oll). After 30 mm hypoxia CoQ,, treated trabeculae exhibited a greater recovery of developed force compared to placebo (46.2+28% vs 640t18%, p=O.OOl). Compared to placebo, CoQ,, patients had a lower release of Tnl(64.5+4.1 vs 39.4&.5 pg/L, p=O.OOOl) and tended to have a shorter intensive care (ICU) stay (40.8r2.4 vs 33.6r2.4 hours, p=O.O56) and had a shorter total length of hospital stay (8.7*2.1 vs 6.8kO.7 days, p=O.O44). Conclusions: Preoperative oral therapy: CoQ,, 1) Increases CoQ,, content in atria1 trabeculae and mitochondria. 2) Improves efficiency of mitochondrial energy production. 3) Improves posthypoxic myocardial contractile function. 4) Reduces myocardial damage. 5) Reduces total postoperative hospital stay

procedure

of cardiac aegiography.

Methods:

A patient having coronary angiography became acutely ill immediately post procedure. Emergency percutaneous coronary intervention (PCI) and stent stabilised the patient’s condition. A helicopter ambulance was called to transport the patient to a facility with cardiac surgery Tbe patient’s condition rapidly deteriorated

doe to an acute ccclwion

of the stent

The patient was tree&d with repeat PC1 and Abciximab. Resuscitation included intubation, ventilation and insertion oftbe IABP. Time delays in transport were mainly due to specific weight rest&ions for the heliccpter, forcing changeover of all equipment such as intravenous pumps to helicopter carried equipment. Weight ofthe IABP is 83kg this was reduced by 26 kg by removal ofthe hospital cart (trolley). lhe patient was loaded to a regular ambulance for transport to the helipad. To load the patient into the helicopter it was necessary to &conned the patient from the IABP for a short time. Results: Transport time by MICA road ambulance has been calculated at 40 minutes, includieg 10 minutes loading and 30 minutes road travel. Transport time by helicopter was 80 minutes 40 minutes preparedness of equipment to reduce weight. 30 minutes to load into ambulance and transfer to the helicopter. IO minutes flight time. Disccemectmn time during loading and unloading from the helicopter was 3 minutes cn each instance. Conclusions: Transport of an acutely ill patient with IABP io site by helicopter ambulance is not recommended. Transfer time is significantly increased A patient reliant on the IABP could be compromised by disconnection time during loading into the helicopter

SHORT-TERM AGGRESSIVE LIPID REDUCTION IMPROVES ISCHAEMIA, VASCULAR ANATOMY AND SYMPTOM STATUS IN PATIENTS WITH ADVANCED CORONARY ARTERY DISEASE RB. Fathi*. B. Haluska . L. Short. P. Garrahv. T. Marwick. Princess Alexandra Hospital, University of Queensland, Brisbane, Australia. Background: Despite symptoms, some pts cannot undergo revascularisation (RVS) because of unsuitable coronary anatomy or co-morbidity Improvement of resistance vessel function by aggressive control of lipids may improve perfnsion, but clinical importance of this is unclear. As dobutamine echo (DbE) directly visualizes ischemia, this technique may be useful to assess the effects of therapy Methods: Forty-four pts with advanced CAD were randomized to either standard care (STD) of lipids or to active treatment (AT) with a target LDL ~2.0 mmol/L (using atorvastatin up to 80mg/day). DbE was performed at baseline and after three months of therapy. Extent and severity of inducible ischaemia was assessed by standard DbE as well as myocardial tissue Doppler velocity (MDV) at peak stress. At baseline and three months, carotid intima-medial thickness (IMT) was measured and the Seattle Angina Questionnaire (SAQ) was administered. Results: Randomization of 23 pts (age 63+7 y) was to standard care and 21 pts (age 64?6 y) to active therapy Reduction of total cholesterol (TC) and LDL with aggressive therapy was matched by improvements in ST change at peak stress, reduction of the number of ischemic and or viable wall segments (ISC), and a trend to reduction of abnormal segments as assessed by MDV. The increase in IMT over three months was less in those on active treatment (0.06 mm, p=O.O8) to those on standard therapy (0.10 mm, p=O.O03). An improved angina1 score was obtained after three months for those on active therapy (p=O.O26) with no significant improvement for those on standard therapy. STD Baseline 3 months P value AT Baseline 3 months P value

TC 4.6*0.8 4.5kO.9 NS 5.1*1.0 3.8+0.9 0.001

LDL 3.0+0.8 2.7t0.8 NS 3.0+0.9 1.9t0.7
ST dev (mm) 0.62t.9 0.65k.8 NS 0.73t.8 0.30+.5 0.05

ISC 3.1+2.4 2.7k2.5 NS 3.Ot1.6 2.1e2.3 0.04

Conclusion: Patients with advanced CAD undergoing aggressive ing demonstrate reduction of ischaemia extent on DbE with improvement of vascular anatomy and symptom status.

MDV 4.1k3.5 4.0+3.6 NS 4.oc3.0 3.4*3.2 0.08 lipid lowerconcomitant

HUMAN CORONARY ARTERY SURGERY WITHOUT CARDIOPULMONARY BYPASS REDUCES NEUTROPHIL ACTIVATION RELATIVE TO SURGERY ON BYPASS M. Vallelv’“, I?. Bannonz. M. Bavfieldz& Hugh&. M. Wonea, L. Kritharidesu Clinical Research Group The Heart Research Institute’, Cardiothoracic Surgical Unit Royal Prince Alfred Hospital*, Dept. Immunology Children’s Hospital Westmead3, Dept. of Cardiology Concord Hospital”, all in Sydney, NSW. Coronary artery surgery without cardiopulmonary bypass (OPCAB) may reduce cardiopulmonary bypass-related (CABG) inflammation. However detailed comparison of neutrophil @‘MN) activation after CABG and OI’CAB has not been undertaken. The relative importance of PMN surface in&grins CDllb and CD18, essential for endothelial transmigration, and PMN degranulation (detected by release of lactoferrin), in CABG- and OPCAB-related inflammation are unknown. Adult patients undergoing elective, first time CABG (n=6) or OPCAB (n=S) had 6 whole blood samples taken before surgery (preop), before and during ischaemia, during reperfnsion 3h and 24h postoperatively (postop). Circulating I’MN were isolated and analysed by flow cytometry for expression of cellsurface CDllb, CD18, and lactoferrin. Total PMN cell counts were also determined. Data are expressed as mean kSEM of “n” subjects, and paired ttest used for comparisons relative to preop samples. OPCAB and CABG subjects demonstrated an identical 3.5-fold increase in total circulating PMN postop (P
A62

49th Annual

Scientific

Meeting

of CSANZ

Heart,

HIGH TRANSTHORACIC ATRIAL DEFIBRILLATION THRESHOLD PREDICTS RECURRENCE OF ATRIAL FIBRILLATION S Nicholls*. L Sava ee. L itch. Department of Cardiovascular Medicine, John Hunter Hospital, Newcastle, New South Wales.

Introduction:

It is unclear

whether

atria1 defibrillation

threshold

(DFT)

is

related to the likelihood of recurrence of atria1 fibrillation. Aim: To investigate time to recurrence of atria1 fibrillation in patients according to atria1 DFT. Method: Forty-four consecutive patients electrically cardioverted from atria1 fibrillation to sinus rhythm were identified. Case records were reviewed and recurrence of atria1 fibrillation during the first 12 months following cardioversion was determined. Transthoracic defibrillation was performed initially at 50 Joules and then increased to 100,200,300 and 360 Joules. DFT was defined as the lowest successful energy required to revert the patient from atria1 fibrillation to sinus rhythm. A low DFT was defied as being less than or equal to 200 joules, and a high DFT was defined as being greater than 200 joules. Results: Mean age was 64 years and body mass index 28.5. Eighty-six percent of patients received antiarrhythmic therapy at the time of cardioversion (32% sotalol, 32% beta blockers, 14% amiodarone and 27% digoxin). 25 patients had a low DFT. Patients with a low DFT were younger (60 vs. 69 years) and had been in atria1 fibrillation for a shorter time prior to cardioversion. Patients with a low DFT were more likely to remain in sinus rhythm during the next 12 months when compared with those patients with a high DFT (72% vs. 2796, p
Lung

and Circulation

2001; 10

SAFETY AND EFFICACY OF PULMONARY VEIN ABLATION THERAPY FOR ATRIAL FIBRILLATION UTILIZING A NEW CIRCULAR MAPPING CATHETER: THE CLEVELAND CLINIC EXPERIENCE S&y& M’NMa D. uchM le MD. W Sali MD. M Chune MD. M Niebauer MD. PhD. R Schweikert MD, P Tchou MD and A Natale MD The Cleveland Clinic Foundation, Cleveland, Ohio, USA. Background: Atria1 fibrillation (AF) is a symptomatically debilitating disease with significant associated thromboembolic stroke and mortality. It is responsible for a large proportion of total health expenditure and is increasing in prevalence with our aging population. The efficacy of pharmacological therapy for the maintenance of normal rhythm is disappointing. Newer therapeutic modalities are currently being explored. Method: We analyzed the outcomes of 61 consecutive patients with AF referred to our EP Laboratory for pulmonary vein (PV) mapping and ablation procedure. Patient characteristics and clinical outcomes are reported. The procedure was performed using conventional fluoroscopy with the use of a circular, pulmonary vein mapping catheter, with or without the complementary use of an electroanatomical mapping system. Pre-ablation PV retrograde injection venography was performed. Spiral CT scanning of the PVs was obtained in all patients 2 months post procedure. Results after a mean follow up of 5 +/- 3 months are presented in the table (LVEF = left ventricular ejection fraction; LA = left atrium; AA = antiarrhythrnic). Results: Patient Baseline Characteristics: Sex Paroxysmal ASWl3 (years) AF 41/20 51+/-U 60% (36/61)

Chronic AF 40 %

LVEF (%) 55+/-S

LAsize bun) 3.9 +/- 0.4

Failed AA Drugs 2.7 +/- 0.8

(25/61)

Post Ablation Outcomes: Acute AF SUCCeSS Recurrence

Fluoroscopy (minutes)

97% (59/61)

101 +/ - 45

21% (13/61)

Duration AF (years) 3.7 +/- 2.2

Chronic success without AADrug 90% (55/61)

Chronic success with AADmg

Failure

8% (5/61)

1.5% (l/61)

Complications: CVA

Acute PV stenosis

Chronic PV stenosis

PV dilatation required

Hematoma

1.5% (l/61)

13% (a/61)

5% (3/61)

1.5% (l/61)

5% (3/61)

Conclusion: an effective

CAVOTRICUSPID ATRIAL FLUTTER AND FOCAL ATRIAL FIBRILLANMF a TION: IS A CAVOTRICUSPID LINE ENOUGH? ‘.. The Cleveland Clinic Foundation, Cleveland, Ohio, USA. Objective: Degeneration of right atria1 flutter (AF) has been previously described. This study ablation in eliminating focal AF.

(AFL) into atria1 fibrillation evaluated the efficacy of AFL

Methods and Results: Out of 64 patients undergoing focal AF ablation 20 (9 men, mean age 52+/-llyears) patients (31%) had a documented history of typical AFL. Successful AFL ablation was performed in 10 patients (50%) 9 + 5 months prior to focal AF ablation (group l), and no AFL ablation was performed in 10 patients (50%) (group 2). In all 20 patients, focal AF triggers originating from the pulmonary veins (PV) (right upper PV 7 patients, left upper PV 10 patients, left lower PV 4 patients) were mapped and ablated. After a mean follow-up of 5 + 2 months, 1 patient from group 1 experienced AF and 1 patient from group 2 had a single episode of typical AFL. None of the patients received anti-arrhythmic drug therapy post focal AF ablation. Conclusion: typical AFL Ablation of appeared to

Focal AF originating from the PVs seems to initiate and maintain in the majority of patients with documentation of AFL and AF. typical AFL is unlikely to eliminate AF. PV isolation alone be the appropriate therapy in most of these patients.

Pulmonary vein isolation guided by circular mapping appears means to cure AF without an associated high risk of complication.

Heart, Lung and Circulation

2001; 10

RADIOFREQUENCY ABLATION FOR CURE OF PAROXYSMAL ATRIAL FIBRILLATION DUE TO PULMONARY VEIN ECTOPY: ACUTE AND LONG TERM RESULTS USING A FOCAL APPROACH l? Sanders*. I. 8. Morton. P. B. Soarks. 1. K. Vohra. 1. M. Kalman. Royal Melbourne Hospital, Melbourne, Victoria. Paroxysmal atria1 fibrillation (PAF) is frequently initiated by focal activity originating in a pulmonary vein (PV). Initial ablation (RFA) techniques for cure of PAF involved targeting these foci (the focal approach). We present the acute and long-term results of focal PV RFA for cure of PAF at a single center. Methods: Fifty pts (34M, 16F, aged 45 + 11.4 yrs) were studied for RFA of PAF over a 3-year period. Pts were considered for RFA on the following criteria: (i) symptomatic drug refractory PAF (> 2 episodes/month and failed a mean of 2 + 0.9 antiarrhythmics) (ii) high density atria1 ectopy or frequent bursts of atria1 tachycardia or PAF on Holter (iii) absence of structural heart disease except mild LA enlargement and (iv) informed consent. Electrophysiology study (EPS) was performed in the drug free state (except amiodarone). Catheters were positioned at the bundle of His, in the coronary sinus, and along the crista terminalis. PV mapping and RFA was by single transeptal puncture, which was only performed in pts with adequate focal activity at the time of procedure. Right atria1 endocardial activation sequence was used to facilitate mapping. Focal activity was present spontaneously or elicited by isoprenaline or burst pacing or AF induction and cardioversion. Results: Transeptal mapping and RFA was not possible in 22/50 (44%) pts; due to inadequate ectopy (17), recurrent persistent AF (l), inability to cross septum (2), foci from > 1 vein (2). In 28 pts in whom RFA was attempted, apparent procedural success was achieved in 23 (82%). PV’s ablated were 14 LUPV, 11 RUPV, 1 LLPV, and 2 RLPV. Mean fluoroscopy time for successful RFA was 29 + 11.5 mins. PV stenosis occurred in one case. No other complications occurred. Recurrence in 10 pts occurred l-120 days (median: 30 days) following RFA. 5/10 pts had repeat EPS with 2/5 being successful. At a mean follow up of 11 f 8 months, 15/28 (54%) remain free of AF and off all antiarrhythmics. Conclusions. Focal PV RFA to cure PAF is successful long-term in only 30% of the screened pts but in 54% of those with focal activity at the time of RFA. Alternate approaches such as PV electrical isolation should be evaluated in order to improve these results.

POSTERIOR LEFT ATRIAL FLOOR-CORONARY SINUS ARE CRITICAL SITES FOR LEFI ATRIAL FLUTTER AFTER ATTEMPTS AT CURATIVE SURGERY FOR ATRIAL FIBRILLATION USING RADIOFREQUENCY ENERGY DI Guv*. SP Thomas. AC Bovd. I Nicholson. G Nunn, RB Chard, DL Ross Departments of Cardiolorv and Cardiothoracic Suraerv, Westmead Hospital. Sydney Since 1995 we have performed 40 intraoperative radiofrequency ablation procedures for atria1 fibrillation utilizing a radial pattern of lesions (Star procedure). Where possible electrophysiology studies (EPS) have been performed at 6 months to allow accurate assessment of operative results. 29 patients have reached 6-months follow-up, and 21 of these have had EPS. Methods: The EPS entails pacing and mapping of both atria to examine lesion integrity and then arrhythmia induction. Initially standard catheter techniques and more recently a non-contact multielectrode array (Ensite) have been used. The posterior left atria1 lines of ablation are of particular interest owing to the thickness of the atria1 muscle near the atrioventicular ring and the possibility of conduction via the coronary sinus or in deep transverse muscle bundles around the lines of ablation. During EPS the coronary sinus electrograms were reviewed, and pacing from distal and proximal coronary sinus performed with atria1 activation pattern used to assess lesion integrity. Results: All 21 patients had at least one flutter morphology occurring either spontaneously and/or with electrical stimulation. Sustained atria1 fibrillation was induced in only 2 patients. Nine of 21 patients studied (43%) had an atria1 flutter that utilised the low posterior left atrium as part of its circuit as determined by entrainment or non-contact mapping. These patients had preserved coronary sinus electrograms in the region of the flutter circuit indicating that the lines of ablation had not been transmural at the atrioventricular junction. Catheter radiofrequency ablation was performed from within the coronary sinus at sites thought to correspond to the inferior portion of the posterior left atria1 lines. In cases with incessant flutter of this morphology the arrhythmia was terminated and in all 9 it was rendered no longer inducible. Conclusion: The low posterior left atrium is a common site of lesion deficiency allowing re-entry around lines of scar. These deficiencies can be ablated from within the coronary sinus. This area should receive special attention at initial operation to ensure complete transmural ablation.

49th Annual Scientific Meeting of CSANZ

A63

LONG-TERM ECHOCARDIOGRAPHIC FOLLOW-UP IN LONE ATRIAL FIBRILLATION. M.A. Barlow*, John Hunter Hospital, Newcastle; G. Klein, R. Yee, A.D. Krahn, University of Western Ontario, London; A. Oi. CR. Kerr. J.B. Boone, St. Paul’s Hospital, Vancouver; S.1. Connolly, MacMaster University, Hamilton; l? Dorian, St. Michael’s Hospital, Toronto; M. Green, University of Ottawa, Ottawa; M. Talaiic, Montreal Heart Institute, Montreal; and of Calgary, Calgary. -,R. Sheldon University Objective: To assess long-term changes in the echocardiographic parameters of patients (pts) with lone atria1 fibrillation (LAF). Methods: A prospective study of 125 pts from the Canadian Registry of Atria1 Fibrillation. A diagnosis of LAF was based upon stringent clinical and echocardiographic criteria. M-mode and 2D/Doppler (2D) echocardiograms were performed at baseline, at 2 years and 4 years. Results: M-mode results -see table. Patient number LAD (mm) LVIDd (mm) IVS (mm) LVPW (mm) LV Mass (g)

Baseline 125 35.7 f 6.3 48.4 + 5.0 9.4 + 1.4 9.3 + 1.4 184.4 + 47.2

Year 4 Visit 50 41.8 + 8.2 51.4 + 8.8 10.6 + 1.7 10.4 f. 1.2 243.4 f 67.1

P value 0.001 0.04 < 0.0001 < 0.0001 < 0.0001

[LAD = left atria1 dimension; LVIDd = left ventricular (LV) diastolic dimension; IVS = interventricular septum thickness; LVPW = LV posterior wall thickness.] ZD/Doa&r results - LV hypertrophy was present in 0% at baseline and 12% at 4 years (p = 0.0004); LV dysfunction in 0% vs 30.0% (< 0.0001); significant mitral valve abnormalities in 0% vs 22% (< 0.0001); and significant aortic valve abnormalities in 0% vs 4% (0.08). Overall, significant 2D abnormalities were seen in 0% at baseline and 58.0% at 4 years (< 0.0001). These Mmode/2D changes were not related to the pattern of AF, whether paroxysmal or persistent. Conclusion: In this group of pts identified with LAF by strict clinical and echocardiographic criteria there were highly significant increases in LV wall thickness and mass and 58% developed significant valvular/LV abnormalities during 4 years of follow-up. These changes are not adequately explained by the presence of AF itself and suggest the presence of unrecognised cardiac disease in a substantial proportion of pts diagnosed with LAF.

VALIDATION OF NON-CONTACT TRICLE USING TRANSMURAL E. Wallace. A. Bovd. V. EiDuer. Department, ~P. Kovoor. Cardiology

MAPPING IN THE NORMAL LEFI VENCONTACT MAPPING. A. ThiazalinPam*, C. Camubell. K. Bvth-Wilson, D.L. Ross, Westmead Hospital, Westmead, NSW

Non-contact mapping using the EnSite system (Endocardial Solutions) can map ventricular tachycardia (VT) including those associated with haemodynamic instability. The EnSite system is capable of recording 3,360 ‘virtual’ electrograms from the chamber studied. We evaluated the effect of pacing site by comparing the unipolar virtual electrograms from the EnSite system with the unipolar signals from plunge needle electrodes recorded on a 256 channel electrophysiology system (Prucka CardioMapp256). Mapping was performed on six male sheep. A grid of 50-60 needles was positioned in the anterior left ventricle at thoracotomy. Each needle had 4 electrodes to record from the endocardium, epicardium and 2 intramural sites. The EnSite multi-electrode array (MEA) was then positioned in the left ventricular cavity The geometry of the ventricle was obtained using a roving catheter. The position of each of the needles was then located on this geometry. Three sheep were excluded from the analysis due to puncturing of the MEA balloon. The results were stratified by the distance of the electrogram recording site to the centre of the MEA and pacing site (epicardial or endocardial). Pearson’s correlation without lag shifting was used for comparison (l=perfect match) to assess both electrogram timing and morphology, Correlations for each distance (mm) for the 3 sheep were (epi=epicardial, endo=endocardial): Sheep 1 Dist. 18-25 26-35 36-42 43.57

Pacing site Endo Epi 0.78 0.77 0.73 0.66 0.67 0.55 0.65 0.53

Sheep 2 Pacing site Dist Endo Epi 18-28 0.75 0.79 28-31 0.68 0.78 31-39 0.65 07 40-44 0.41 0.38

Sheep 3 Pacing Dist Endo 25-33 0.71 34-37 0.73 3840 0.66 41-47 0.56

site Epi 0.73 0.76 0.72 0.63

In conclusion, virtual electrograms from non-contact mapping are accurate if the array is located within 28 mm of the recording site regardless of the origin of the electrical activity (endocardial or epicardial pacing). In clinical practice, careful positioning of the MEA will ensure accurate virtual electrograms whether the VT focus is in the epicardium or endocardium.

A&j

49th Annual

Scientific

Meeting

of CSANZ

STAGED PALLIATION OF PATIENTS WITH SINGLE VENTRICLE PATHOLOGY AND ARCH OBSTRUCTION WITHOUT CIRCULATORY ARREST - FOCUS ON THE TIMING OF DAMUS-KAYE-STANSEL (DKS) CONNECTION. Win&*. D. Andrews.R.Chard. I Nichalsan, S. Coooer. G.R. Nllna Adolph Basser Cardiac Institute. Children’s Hospital at Westmead, Sydney. Retrospective evaluation of repair strategies for neonates with double inlet left ventricle and I-tga, and similar lesions. These often present with arch obstruction and duct-dependent circulation necessitating early repair. ‘Primary’ repair utilizing a Norwood type approach may be performed. Our group has preferred to repair the arch and limit pulmonary blood flow initially, deferring the DKS to a point when cave-pulmonary connection can also be performed. Potential narrowing of the bulboventricular foramen (BVF) may warrant early unloading of the systemic ventricle. Incompetence of the pulmonary valve remains a concern. Our strategy was examined in the 19 patients who underwent DKS since 1990. Arch repair and PA banding was performed by thoracotomy with a second stage DKS and cavopulmonary connection at a median of 14 months after the first operation. At the second stage, 2 patients required repair of the pulmonary arteries because of the pulmonary band. To date the Fontan circulation has been achieved in 11 of 19 patients at a median 48 months later. A subset of children where BVF narrowing was not initially apparent (4) underwent completion Fontan but subsequently required DKS. This was performed by resurrection of the pulmonary valve (3) and xenograft (I). There was one unrelated death 9 months post operatively. The remainders are well with good physical capacity, with no obvious neurological injuries, no instances of semilunar valve distortion, no progressive incompetence nor ventricular dysfunction.

Heart,

LATE CLOSURE OF PERSISTENT FONTAN REPAIR N.T. Finucane Green Lane Hospital, Auckland,

Lung

and Circulation

FENESTRATIONS New

2001; 10

AFTER

THE

Zealand

Our unit has not had a policy of early routine fenestration closure after the Fontan (F) operation as some fenestrations undergo spontaneous closure. Nevertheless continued desaturation may contribute to ongoing ventricular dysfunction and symptomatology We recently undertook to close fenestrations in patients whose saturations were < 90%. The purpose of the study was to review these patients. Six patients, aged 6-17 years, underwent transcatheter closure of surgically created fenestration 4.7 + 1.7 years after the F. All patients had undergone a lateral channel F using Gore-Tex with a single 4mm fenestration between 1994-8. Symptoms included exercise impaiment (4) and headaches (1); 2 were asymptomatic. Ventricular function was normal/mildly impaired in 4, moderately impaired (l), severely impaired (1). Saturations were 81+ 3%. All patients underwent cardiac catheterization including balloon test occlusion of the fenestration. The mean cavopulmonary pressure rose from 9 + 2 to 12.5 f 3 (p < 0.001) but there was no significant decrease in cardiac output with the arteriovenous difference increasing from 22 + 7 to 26 + 6 (p = NS). Fenestration closure was by CardioSea1 umbrella (2), Gianturco coils (l), Amplatzer Septal Occluder (3). Two patients had small concomitant baffle leaks with no attempt to close these. At most recent follow up saturations are 92 + 2% and 5 of 6 patients report improvement, 4 improved exercise tolerance and 2 improved mental performance. Conclusion. Late fenestration closure is associated with symptomatic improvement and can be considered at any time interval after the Fontan repair. Ventricular dysfunction is not necessarily a contraindication to fenestration closure.

Good results have been achieved with delayed DKS utilizing a strategy that avoids circulatory arrest and extensive surgery in a sick neonate. Small numbers of patients representing with late BVF narrowing suggest that early DKS connection should be performed in patients with susceptible pathologies, as part of the repair strategy.

CONVERSION TO AN EXTRACARDIAC CONDUIT WITH A LIMITED RIGHT ATRIAL MAZE PROCEDURE FOR THE FAILING FONTAN WITH ATRIAL TACHYCARDIAS. S.P. Settv, A. K. Finucane*, A. R. Kerr, J. R. Skinner. Cardiac Surgery and Cardiology Units, Green Lane Hospital, Auckland. Reduction of right atria1 (RA) pressure and wall tension by conversion to an extracardiac conduit combined with reducing right atria1 (RA) size should improve haemodynamics and reduce the development of late atria1 tachyarrhythmias. However, atnal tachycardias may still persist and more effective control may he achieved by interrupting atria1 arrhythmia circuits and insertmg pacemakers at the time of the Fontan revision. Smce 1997, we have performed this operation in 5 patients aged 14 to 28 years (mean 20.6) at an average of 13.5 ? 4.4 years after then All of the patients had medically original Fontan procedure. uncontrollable atrial tachyarrhythmias and grossly dilated right atria wifh markedly reduced exercise tolerance. Along with extracardiac conduit insertion, each patient underwent a limited RA maze procedure using a combination of cryotherapy and incisions in addition to RA reduction. All had epicardial pacemakers. All the patients survived with an average hospital stay of 18 days (7 - 38). Exercise tolerance has improved in all five and atnal tachycardias have either decreased (2) or disappeared (3). Only one patient is on an ant&rhythmic medication other than Digoxin. Follow-up is a mean of 20.4 months (6 - 38 months). Without compromising safety this technique gives a better chance of longterm relief from debilitating and persistent atria1 tachycardias in the failing Fontan. RA maze, size reduction and pacemaker implantations are worthwhile additions to simple conversion to an extracardiac conduit in the failing Fontan. Without compromising safety this gives a better chance of longterm relief from debilitating and persistent atria1 tachycardias.

ALLOGRAFT PATCH AORTOPLASTY FOR COARCTATION REPAIR IN NEONATES AND 1NFANTS.H. Talsli*. 1. Lamblev, P. Pohlner. B. TaPannath. The Queensland Centre for Congenital Heart Disease, The Prince Charles Hospital, Brisbane Australia OBJECTIVE: To study early and mid-term outcome of allograft patches for coarctation repair in neonates and infants. To compare intraoperative and postoperative results with other widely used methods. METHODS: From January 1996 until December 1999, 106 patients werr operated on for coarctation repair. Pulmonary artery allograft patch aortoplasty was used in 33 children (age one day - 16 months, mean 2.5 months). In 31 cases a primary procedure was performed. A further two were done following attempted resection and end to end anastomosis (1) or subclavian flap repair (1). 29 coarcts were of the juxtaductal type with 4 having additional arch hypoplasia. 12 were isolated, 11 had other simple congenital defects and a further 10 had complex congenital heart disease. Follow-up ranged from 1 to 43 months (mean 15 months). RESULTS: Them were no operative mortality or paraplegia. There were 3 balloon angioplasties and 2 reoperations for recurrent coarctation. All other children remain free from further recurrence with echocardiograms excluding peak gradients in excess of 20mm Hg. CONCLUSIONS: Early to mid-term results suggest that allograft patch aortoplasty is comparable to other surgical treatment modalities. Its flexibility and versatility of use may be advantageous in repair of coarctation and/or arch repair in neonates and infants. Long-term data for use of allografts in this setting is not available yet but one may anticipate that it has the potential to rival its performances in other positions.

Heart, Lung and Circulation

49th Annual Scientific Meeting of CSANZ

2001; 10

NEW INSIGHTS INTO LEFT VENTRICULAR REGIONAL FUNCTION: COMBINATION OF LONG-AXIS AND RADIAL MYOCARDIAL VELOCITY OFFERS A NEW QUANTITATIVE PARAMETER, INDEPENDENT OF SEGMENT LOCATION. P Cain*. L Short, C Case, T Marwick, University of Queensland, Brisbane. Background: Tissue Doppler may quantitate regional LV function but is limited by segmental variation of long axis velocity from base to apex and free to septal walls. We sought to produce a composite of long axis and radial velocities to overcome this regional variation. Methods: We examined 53 pts undergoing a standard dobutamine echo (DbE). Long axis velocity (LAV) was obtained in the basal and mid segts of each wall using tissue Doppler in the apical views (GE Vingmed S5). Radial velocities (RAV) were derived in the same segts using an automated border detection system and improved centerline method (Echo-CMS,Medis) with regional splines grouped according to segt location and temporally averaged. Wall motion (WMS) was assessed by an experienced reader. Results: Table shows long axis, radial and composite velocity in 14 normal pts, compared according to location (base vs mid LV, free wall vs septal). The pattern of regional variation in LAV (higher in septum) was the opposite of RAV (higher in free wall) and the combination was homogenous. In 39 pts with CAD, velocity in abnormal segts was less than normal segts using long axis (624 vs 9+3 cm/s, p=O.Ol) and radial velocity (6*4 vs 8+4 cm/s, p=O.O2). However, the composite velocity permitted better separation of abnormal and normal segts (1355 vs 1725 cm/s, p=O.OOl). LAV SAV

Base-f/wall 7.oe3.0 9.0+3.5

Base-septal 8.5i-3.2 7.2k2.7

Comb.

15.6e3.0

15.7*3.0

Mid-freewall 5.9i3.2 8.Ok3.6 14.3t4.0

Mid-septum 7.2k2.8 6.8+2.5 14.2+3.1

p 0.001 0.005 0.68

Conclusions: Regional variation of uni-dimensional myocardial velocities, probably due to different fiber directions, necessitate site-specific normal ranges. Combined analysis of long-axis and radial velocities allows the derivation of a composite velocity which is homogenous in all segts and may allow better separation of normal and abnormal segts.

CAN STRAIN AND STRAIN RATE QUANTIFY REGIONAL RIGHT VENTRICULAR MYOCARDIAL FUNCTION? A STUDY IN NORMAL SUBJECTS M. Kowalski*. L.A. Simmons , T. Kukulski. F. lamal, 1. D’hooge, E Weidemann. B. Biinens. L. Hatle. G.R. Sutherland University Hospital Gasthuisberg, Leuven, Belgium Aim: Quantification of regional right ventricular (RV) myocardial function is difficult using current methodology. Ultrasound based 1-D Strain (E) and Strain Rate (SR) can characterize local myocardial deformation by determining the local in - plane spatial velocity (Vel) gradient. The aim of our study was to define normal segmental E /SR profiles and values for both radial and longitudinal function of all RV lateral wall. Methods: High frame rate (>I20 fps) Color Doppler data sets were collected from 40 normals (20-44 y; 11 F) using standard parastemal and apical 4 chamber views. RV free wall thickness (<6mm) did not allow accurate post processing of radial E and SR values using current technology. Thus, maximal systolic Vel, E and SR were processed off-line only for longitudinal deformation of the RV free lateral wall (basal, mid- and apical segments). They were compared to the values obtained from the corresponding segments of the LV lateral wall. Results: Both for the RV free lateral wall and for the LV lateral wall, baseapex velocity gradients were present with highest Vels at the cardiac base. In contrast, in the RV free lateral wall, E and SR gradients were inverted (the highest values being derived from the apical segments). In the LV lateral wall E /SR profiles were homogeneous (See table).

Vel(cm/s) SR(s/-1) E W)

RV lateral wall basal mid9.72’+2.26 &X65+2.31 1.50*+0.41 1.72kO.27 19+6’ 27t6

apical 6.6Oi2.05 2.04+0.41 32~6

LV lateral basal 8.66’r2.40 1.19tO.26 13+4

wall mid7.90~2.42 1.12*0.2x 14+4

apical 7.09~2.44 1.25t0.39 15*5

*has vs mid- YS api p
TRANSTHORACIC TIVE PREDICTIVE CY Ho. O.B. da Silva, Hospital, Boston, MA,

A65

ECHOCARDIOGRAPHY HAS EXCELLENT NEGAVALUE IN SUSPECTED ENDOCARDITIS M Lund*, F Louez-limenez. SD Solomon. Brigham and Women’s USA

Objectives: To assess the diagnostic value of transthoracic echocardiography (TTE) as a screening test in patients with suspected endocarditis. Methods: 132 paired studies from patients who underwent TIE followed by omniplane transoesophageal echocardiogram (TOE) within 1 week for suspected native valve endocarditis between January 1996-November 2000 were evaluated. Three independent echocardiographers blinded to TOE results reviewed TTE studies. TTEs were classified by both strict criteria: positive (+=definite vegetation or abscess), indeterminate (+= non-specific focal thickening), or negative (-); and by broad criteria: positive (+= vegetation, abscess, non-specific focal thickening, mitral regurgitation (MR) or aortic regurgitation (AR)) or negative (-). The TOE results were similarly reviewed and classified as (+), (+), or (-) for vegetation by strict criteria. TOE findings were used as the standard of reference in defining valvular vegetations. Results: TTE Criteria/ TOE Reference Broad with TOE (+)

Sens 17/17(100%)

Spec

43/115 (37%)

(+)LR 1.6

Strict (+) or (+) with TOE (c)

12/17 (71%)

89/115 (77%)

3.1

Broad with TOE (+) or (+)

26/29 (90%)

40/103 (39%)

Strict (+) or (*) with TOE (+) or (t)

16/29 (55%)

&?1/103 (79%)

1.5 2.6

G)LR 0 0.38 0.25 0.57

NPV 100% 95% 93% 86%

(Sens =sensitivity; Spec =specificity; (+)LR =positive likelihood ratio; (-)LR = negative likelihood ratio; NPV =negative predictive value). In 43/132 (33%) patients with negative TTEs using the broad criteria, no cases of defimte vegetations on TOE were missed by TTE. Conclusions: Patients with suspected endocarditis who have a definitively negative TTE are unlikely to have vegetations detected on TOE. Utilizing a screening strategy in which the NPV of TTE is maximized may reduce the number of unnecessary TOES performed.

CAN CONTRAST ECHO IDENTIFY VESSEL PATENCY IN ACUTE INFARCTION: COMPARISON WITH PREDICTION OF TIM1 FLOW USING ECG ANALYSIS B Haluska. L Short, l’ Garrahv. R Lim. T Marwick* University of Queensland, Brisbane, Australia Background: Vessel patency in myocardial infarction may influence intervention, but standard markers (chest pain, ST segts) have limited accuracy. Myocardial contrast echo (MCE) may identify vessel patency; we sought whether MCE could be introduced as a clinical tool. Methods. 53 pts (age 65+13, 46 men) with acute infarction and ST elevation were studied with MCE just prior to coronary angiography. MCE was performed using harmonic imaging on standard equipment, with end-systolic triggering at 1:4, 1:6, 1:s and 1:lO after Optison infusion. Perfusion images were obtained in gray scale and power Doppler (HPD) at baseline and during infusion in each view. Images underwent digital subtraction and color coding @CC), and perfusion was scored in each territory. Degree of ST elevation (summed in all leads) was obtained on the first ECG and after an average interval of 2 hrs. Ability to identify perfusion according to TIM1 score was evaluated by comparison with angiography (‘p
100%

see

91% 65%’

HPD

T2 80% 60% 100%

T3 88% 88% 100%

NOIIlUl 83% 22% 22%

N in abn pts 18%

15%

The difference between SCC and HPD in TIMI O-l (p=.O2) reflected a difference in RCA sensitivity (100% vs 42%, p=.OOl). Both MCE methods showed perfusion defects with TIM1 3 flow, and ECG changes were seen with normal flow.

Conclusions: MCE is feasible in acute MI and may avoid false positive ECG. HPD offers on-line images but is limited in the inferior wall. However, perfusion defects are prevalent even in pts with TIM1 3 flow.

A66

49th

Annual

Scientific

Meeting

of CSANZ

Heart,

CAN RISK ALLOCATION BY STRESS ECHO IDENTIFY “TREATABLE RISK” AND BE USED TO GUIDE MANAGEMENT IN PATIENTS WITH KNOWN OR SUSPECTED CAD? Case.)!‘ C S Sawada. T Marwick* University of Queensland, Brisbane, Australia; Asheville Cardiology, North Carolina; Indiana University, Indianapolis, Indiana Background: Results of clinical evaluation and stress echo are known to stratify risk of death in pts with known or suspected CAD. However, as these models incorporate factors that are not or are minimally amenable to intervention (age, diabetes), these models might merely predict pts likely to die rather than those whose risk may be ameliorated by intervention. We sought whether revascularization altered outcome in pts with 5 levels of risk predicted by stress echo. Methods: Exercise or dobutamine echo was performed at 3 centers in 5864 pts with known or suspected CAD. Clinical, stress and echo parameters were gathered prospectively. For each pt, risk was attributed on the basis of a previously derived logistic regression (which includes age, gender, heart failure, resting LV function, workload during stress and the presence of ischemia); pts were grouped into quintiles of risk. Event rates were recorded for pts treated medically and with revascularization. Results: Over follow-up, 1146 pts died. Revascularization (n=590 pts) was associated with lower mortality in each group apart from those at lowest risk;

Lowest quintile Second quintile Third quintile Fourth quintile Fifth quintile

n

Expected mortality

Mortality in revascularized

Mortality in medical Rx

1163 1183 1150 1203

4.6% 9.3% 15.6% 23.8% 43.3%

4.3% 3.1% 4.0% 11.2% 17.6%

4.7% 9.8% 17.1% 25.8% 47.9%

1170

p 0.70 0.01
Comparison of revascularized with medically-treated patients after adjusting for risk showed a relative risk of 2.0 (1.5 - 2.8) associated with non-revascularization. For pts at significant risk (ie. those in quintiles 2-5), there was no difference in age (63 vs 64 yrs, p=O.O64) or peak RPP (22.623.0 x 1000 p=O.19) for the revascularized and medically treated groups; heart failure was more prevalent in revascularized pts (despite better outcome). In contrast, pts in the lowest risk category who were revascularized were older than medically treated pts (46 vs 40 yrs p=O.O04) and had slightly lower PREP. Conclusion: Allocation of risk at functional testing appears to represent “treatable risk” in that outcome of revascularized pts is better than medically treated pts.

Lung

and

Circulation

2001; 10

TROPONIN T MEASUREMENT FOLLOWING CORONARY BYPASS SURGERY, USING THE 3RD GENERATION TROPONIN T ASSAY R.A. Baker*. R Tirimaccol .TL Cardiac Surgery Research, Cardiac Services’, l&riders Medicai Centre, Adelaide, South Australia, 5042. Troponin T (TnT) is a valuable indicator of myocardial ischemia, with a characteristic release pattern. A detailed understanding of the release pattern following coronary bypass graft (CABG) surgery has not been available. Current evidence suggests an elevation following bypass surgery, with a return to baseline levels. The new 3d Generation assay has necessitated re-evaluation, as the assay is calibrated differently, resulting in lower TnT values. Roche Diagnostics have also reported problems with the use of heparin-plasma TnT samples. Aims: To assess heparin-plasma to demonstrate the release profile

versus serum sampling on TnT values, of TnT following CABG.

and

Method: 143 routine TnT samples (51 patients) were taken in duplicate (one serum, one plasma) to determine the correlation between TnT level measured by each method. Release profiles from 44 patients following CABG were compared (19 2”d generation, 25 3” generation assay). Results: The correlation between the TnT measured in serum versus plasma was highly significant (R2 = 0.9792). TnT measured in plasma resulted in an overestimation of 14.6% (+/- 15.2). Serial sampling demonstrated a peak release 6-8 hr after the initiation of myocardial ischemia during CABG surgery. The peak was present with both generations of the assay. 21 of 24 (88%) patients demonstrated a peak with the 3rd generation assay, whilst 95% showed a peak with the 2nd generation assay. Perioperative infarction produces a sustained elevation of the measured TnT, resulting in a release profile distinctly different from normal. Conclusion: TnT measurements must be made from blood serum samples for routine clinical assessment of myocardial ischemic damage. Following cardiac surgery a distinctive release profile is demonstrated.

ARE MITRAL ANNULAR VELOCITIES IN PATIENTS WITH SEVERE LEFT VENTRICULAR DYSFUNCTION AND SIGNIFICANT MITRAL REGURGITATION FLOW DEPENDENT Jl Pereira”. I Vlassak. L Kine, p The Cleveland Clinic Foundation, Cleveland, Ohio, USA and St Vincents Hospital, Melbourne, Australia.

ANALYSIS OF NEUROPSYCHOLOGICAL DEFICITS 6 MONTHS AFI-ER HYPOTHERMIC AND NORMOTHERMIC CORONARY ARTERY BYPASS SURGERY. -Andrew*. I.L. Knight. Cardiac Surgery Research, Health Psychology’, Flinders Medical Centre, Adelaide, South Australia, 5042.

Background: Myocardial annular velocities (MAV) measured by Doppler tissue echocardiography (S, E‘, A) are useful for assessing both systolic and diastolic function in patients (pts) with left ventricular (LV) dysfunction. However it is unclear if an increased stroke volume due to mitral regurgitation (MR) results in increased MAV thus masking the presence of abnormal systohc and diastolic function. Methods: We studied 43 pts with heart failure secondary to a dilated or ischemic cardiomyopathy There were 29 pts with 5 2+ MR (Group (Gp) 1) and 14 pts with > 2+ MR (Gp 2). These were compared with 21 asymptomatic pts with >2+ MR and normal LV ejection fraction (LVEF) (Gp 3). Results: The LVEF in Gp 1 pts = 26r7%, Gp 2 pts = 21&7%, (l’ = 0.05, Gp 1 v 2) and in Gp 3 pts = 73+7% (P < 0.001, Gp 3 v Gp 1 and 2). The LV end diastolic volume = 249+87 mls in Gp 1 pts, 227+64 mls in Gp 2 pts, (P = NS, Gp 1 v 2) Go and in -E/A Lat s Lat E E/Lat E DT (msec)

Normothermic whole body perfusion has been advocated as an advantageous management strategy for coronary artery bypass surgery (CABG), however debate still surrounds the impact on postoperative neuropsychological (NE) functioning.

GPl G;2

1.1*0.9

221+78

7.8+3.0

9.7k4.0

7.4i3.2

7.8e2.0 t2.5*1.7 t139*52 t5.6k0.9 t14.1t4.1 Gp3 j1.7+0.5 §205+34 $11.9+3.0 $14&3.9 @3.2?3.3 tr < 0.001, Gp 1 Y 2. tl’ < 0.001, Gp 3 v Gp 1 and 2. §l’ < 0.001, Gp 2 Y 3. jl’ = 0.01, Gp 1 v 3. Among all pts, there was a good correlation between LVEF and S (r = 0.7) however there was a weak correlation between the severity of MR and S (I = 0.3) Conclusion: 1) The presence of severe MR in pts with cardiomyopathy is a marker of poor diastolic function. 2) In the presence of significant MR, transmitral flows are considerably increased, but there is a limited increase in MAV 3) As a result, the utilization of MAV in pts with significant MR and cardiomyopathy remains useful.

One hundred and twenty six elective CABG patients were randomised to receive either normothermic [systemic normothermia and intermittent warm (37°C) blood cardioplegia; n=65] or hypothermic [systemic hypothermia (30-32°C) and intermittent cold blood cardioplegia (8-10°C); n=58] surgery. NP assessments were performed preoperatively (Tl), 7 days (T2; n=123), and 6 months postoperatively (T3; n=91). Reliable change indices were used to calculate incidence of Nl’ deficits. The two groups were demogrphically comparable. Bypass and x-clamp times were similar for both groups, with the average number of grafts 2.3i0.8 (hypothermic) versus 2.5kO.8 (normothermic). There were no differences between the groups on incidence of neurological injury, or the combined endpoint of ICU hr >48, length of stay >lO d, and 30-d mortality The normothermic group displayed a significantly lower incidence of deficits than the hypothermics on Pegs RL at T2 (4.8%vs15.8%), and TMT A at T3 (8.3%~~ 26.1%). By T3 there was a significant reduction in the incidence of deficits on many NP measures in both groups. There were no group differences on the number of NP measures per patient with deficits at T2 or T3. In the normothermic group there was significant T2 to T3 reduction on the number of Nl’ measures per patient with deficit (p=O.O4). Normothermic thermic bypass.

bypass

provides

cerebral

protection

comparable

to hypo-

49th Annual Scientific Meeting of CSANZ

Heart, Lung and Circulation 2001; 10

THE CHANGING FACE OF NEUROPSYCHOLOGICAL DEFICITS FOLLOWING CARDIAC SURGERY. M.I. Andrew*. R.A. Baker. AC. Kneebong‘ J L Knieht. Cardiac Surgical Research, Health Psychology’, Flinders Medical centre, Adelaide, South Australia, 5042.

MYOCARDIAL INFARCTION IN THE YEAR PRIOR TO CABG SURGERY ASSOCIATED WITH WORSE LONG-TERM SURVIVAL BUT HAS LESS EFFECT ON SHORT-TERM SURVIVAL. PJ Bradshaw*, PL Thompson, K Jamrozik, I Gilfillan, TQ Le. Department of Public Health, University of Western Australia. Perth WA

The evaluation of subtle neurological outcomes following cardiac surgery using neuropsychological (NP) assessment has gained popularity over the last decade. Initial incidence rates of postoperative Nl’ deficits approached 79%, and resulted in a greater awareness of strategies aimed at minimising the risk of these deficits. Since 1996 the incidence of postoperative NP deficits has been recorded for a cohort of cardiac surgical patients at our institution. The subject group consisted of patients undergoing elective cardiac surgical procedures between 1996 and 2000 that were administered a standardised battery of NP measures preoperatively and 6 months postoperatively. The sample has been categorised into double graft (n=68), multiple (23) graft (n=67), valve (n=30), and combined valve/graft (n=14) procedures. Reliable change indices were used to define the incidence of NP deficits.

The effect of prior myocardial infarction on survival after coronary artery bypass surgery (CABG) was studied in a Western Australian population study of 8910 patients who had isolated index coronary artery bypass graft (CABG) surgery between January 1980 and March 1993. Patients who had an acute myocardial infarction (AMI) recorded as a discharge diagnosis in the year prior to CABG were at greater hazard of death in the medium to longterm. The small increase in risk of death at 30 days for males who had a prior AMI (1.9% vs. 1.5% 2p=O.16) and females (3.2% AMI vs. 2.7% 2p=O.67) was not significant but an increased risk was apparent from 12 months after CABG. Estimated mean survival was 13.7 years (95% CI 13.5 to13.99) for those with prior AM1 vs. 14.1 years (95% CI 14.02 to 14.4) (log-rank test 5.78, df 1, p=O.O16). Estimated survival % and numbers surviving

In the 1996-1997 patient group the incidence of NP deficits across all procedure categories ranged from 0 to 36.8%, with the valve and valve/graft procedures particularly affected. The measures most susceptible to persistent deficits at 6 months were Trails A and B (range from 10.9% to 31.6%), and Digit Symbol (range from 8.7% to 36.8%), with the valve/graft group also displaying a high incidence of deficits on measures of memory. By comparison the incidence of deficits from the 1998-2000 period were consistently lower for all procedure categories. The Trail making A and B measures still exhibited deficits in up to 20% of multiple graft patients, although for many other NP measures the incidence of deficits had reduced to 0 in all procedure groups. These results indicate a marked reduction the time period from 1996 to 2000.

in the incidence

of NP deficits

A67

1.0 .8

Black line, prior AMI. Grey line, no prior AMI

.6

si f

.4 P

cl . .. , .. . .,

over

0

5

10

15

20

Years after CABG

WORSE LONG-TERM SURVIVAL AflER CABG IN FEMALES ASSOCIATED WITH AGE AND RELATIVE UNDER-UTILIZATION OF INTERNAL MAMMARY ARTERY GRAFTS. PI Bradshaw’, PL Thomuson, K Jamrozik. I Gilfillan, Le T Q. Department of Public Health, University of Western Australia, Perth WA. A population-based study with up to 20 years follow-up provided an opportunity to assess the relationship between the patient’s sex and long term survival after coronary artery bypass surgery (CABG). In 8910 patients undergoing isolated first CABG between January 1980-March 1993 in Western Australia, survival was determined by record linkage to the WA Linked Database and the National Death Index. Thirty day survival was significantly worse for women. The odds ratio for female gender was 1.39 (95% CI 1.003 to 1.94 2p=O.O47) after adjusting for age and other factors. Crude thirty-day Males ( Females) %

1980-84 0.4 (1.1)

mortality

1985-89 2.7(3.0)

1990-1993 1.6 (4.3)

2P


Long-term survival after 30 days was also worse for women (log-rank test 11.38, df 1, p 0.0008) overall (see figure). However in multivariate analysis the odds ratio for long-term survival was 0.91 (95% CI 0.84 to 0.99 2p=O.O4) for female gender. Much of the apparent difference in long-term survival in women compared with men can be attributed to the older age at which women come to surgery (median age for women was at least 4 years greater than that for men in each period) and the resultant underutilization of internal mammary artery (IMA) grafts (41% in males and 35% in females), both of which are signifi1.0 cantly associated with poorer surBlack Ime, males. Grey line, females. vival. Age-related co-morbidity may also influence survival but rel.(I evant data on these were not available. .6 Conclusion worse long term sur- 1 viva1 of women after CABG is due E .4 to their older age at the time of 2 surgery and relative under-utilizaE .2 tion of IMA grafts. 0’

Prior AMI

1 year

Yes NO

96.0% 96.6%

2896 5697

5years 86.9% 89%

1OYCdIS

2622 5291

70% 73%

1258 2753

15years 54% 360 55% 1010

Conclusion: In a state-wide population followed for up to 20 years, an AM1 in the year prior to CABG was associated with a non-significant increase in risk of death at 30 days which increases to a 3% difference at 10 years and reduces thereafter.

IMPROVED SURVIVAL IN CORONARY ARTERY BYPASS GRAFTING USING THE RADIAL ARTERY. l? Ruenesakulrach. I. Fuller, A. Rosalion. G. Matalanis. 1. Raman. I. Gordon. B. E Buxton* Cardiac Surgery Department, Austin & Repatriation Medical Centre, Heidelberg, Vie. Recently, there has been a trend within coronary artery bypass grafting (CABG) towards using complete arterial grafting. The objective of this study was to examine whether there was any survival difference associated with using the right internal thoracic artery (RITA), radial artery (RA) or saphenous vein (SV) in conjunction with the left internal thoracic artery (LITA). One thousand two hundred and thirty one patients who underwent CABG between January 1995 and June 2000 using two conduits were reviewed. All patients received the LITA as their first graft. The second graft used was the RITA (333, 27.1%), the RA (700, 56.9%), or the SV (198, 16.1%). Patients were followed-up over 32.9 t18.8 (mean + SD) months. Cox’s proportional hazards method was used to analyze risk factors for post-operative death. The 16 risk factors considered were age, gender, diabetes, hypertension, peripheral vascular disease, carotid disease, cigarette smoking, aortic stenosis, aortic regurgitation, mitral regurgitation, acute myocardial infarction, urgency of surgery, ventricular function, type of second graft, number of anastomoses, and surgeon involved. Forty-one patients died during follow-up. The risk factors for death found to be significant were age (P=O.O3), urgency of surgery (P=O.O06), ventricular function (P=O.O12), type of second graft (P=O.O3), and aortic stenosis (P=O.OOS).

6 Years

5 after

lb CAGG

. l’s

.

2b

The survival rate after CABG was significantly better in the patient group receiving the RA rather than the SVG as a second graft, controlling for the other 15 potential risk factors for death.

j&3

49th Annual Scientific Meeting of CSANZ

Heart, Lung and Circulation

INCREASE IN CIRCULATING TUMOR NECROSIS FACTOR a FOLLOWING ACUTE CARDIOGENK PULMONARY OEDEhU \ De Am01 LF,cardiac, Critical Care and physiology Dqmvunents Flin&rs Medical Ceoire, SA, Australia Circulating tumor neachs factor a (TNFa) is elevated io congest& heart failure (CHF) and is known to mince left ventricular conhactile fuoctioo sod promote cachexia, polmooaq o&ma and ventricular remodeling TNFa io prodwed by the myocardinm following numerous insults iochtding simple hemodynmk slress. Conseqnently cirnulating TNFcx may be elevated following acute cardiogeoic nulmonmv o&ma WFOk however this has not m-eviouslv been shown. days 1,3,7&d

14.

scored for clinical signs of plmomy oedema at the same lime points. Chest-X-rays were scored for extravascutar lung water (EVLW) and arterial oxygen to inspired oxygen ratio ([email protected]:FQ) was determined TNFa levels ware measamzl in an age matched control group without inflammatory or cardiac disease. Circulating TN% was elevated at pwatation Q.KO.05). levels rose tiuther at 24 hours wO.05) and remained elevated for more than 72 hours m.05). In contrast cliical markers of @nwnary o&ma impoved rapidly after presentation; chest-x-ray EVLW reduced at day 3 (m-m 4624 to 6.7f1, p
Clinical Pulmonary oederna soore -a-

I, 01

I 3



Time PoQt Pr&eMtion

(Day;

Since the immunologic dimination t’/l of TNFa short (minutes) the disassociarion between TNFa levels and clinical iqxovement (hence hemodynamic stress) suggests anaRemativesourcetothemyocaniinm wespecukethatthehmgmaybethesoluce in this setting as it is rich in TNFa producing cells and is adversely effected by plmonary oedema.

2001; 10

REDUCED MYOCARDIAL L-ARGININE EXTRACTION IN HEART FAILURE: A MECHANISM FOR IMPAIRED CORONARY ENDOTHELIAL FUNCTION? : DM _ e’ art’ hnston. Heart Centre, Alfred Hospital and Baker Medical Research Institute, Melbourne, Australia. Congestive heart failure (CHF) is a common cardiovascular disorder with complex pathophysiology. In addition to impaired ventricular performance and neurohormonal activation, it is increasingly evident that endothelial dysfunction is a common feature of CHF. This latter abnormality has been observed in most vascular beds, including the coronary vasculature, and may be improved by the administration of the nitric oxide precursor L-arginine. Our group has recently reported that the abnormality of vascular function in the forearm of CHF patients may be explained by impaired transport of Larginine by the endothelium. ln the current study we aimed to extend these studies to investigate whether a similar process could be identified, to provide a potential mechanism for altered coronary endothelial function in CHF patients. We studied 8 pts with moderate to severe CHF (LVEF 15+4%, NYHA 2.94.1) and 9 healthy age matched controls. During a steady state intravenous infu sion of 3H-Larginiie, patients underwent right heart catheterisation (Swan Ganz) and coronary sinus catheterisation for measurement of coronary sinus blood flow and coronary sinus blood sampling. Arterial pressure and blood samples were taken from a radial arterial line. Consistent with the clinical severity of the CHF, haemodynamic parameters were significantly impaired in CHF patients compared to controls: cardiac output 4.0~0.3 vs 5.49.2 L/min p
NOVEL “HEART PATCH” DIRECT CARDIAC COMPRESSION DEVICE (DC0 FOR SUPPORT OF THE FAILING HEART. S Hunvor’.‘. S Plekha o , Y Huang. Cardiac Technology Centre, Depts of Cardiology & Cardio&&c Surgery, Royal North Shore Hospital, St Leonards NSW 2065, Mechanical assist (MA) for heart failure (HF) is progressing rapidly and addresses a growing need for the expanding population of HF sufferers. Heart rejuvenation techniques offer further scope for periods of mechanical support. Basically, MA can be divided into “flow-through” (pulsatile & nonpulsatile) and “non-blood contacting” (direct cardiac compression - DCC) devices. The former require access to the central circulation and pose constant risk of thrombo-embolism. They have no safe failure mode, risk immune consumption and can be difficult to remove. We have worked on the development of a simple to install non-blood contacting, non-surround DCC device. The hemodynamic performance of the DCC prototype was assessed in sheep some weeks after its implantation under anesthesia through a 4” left intercostal thoracotomy. Aortic flow was monitored by implanted Transonic flow probe and pressure by Millar catheter tip manometer. IV esmololl.67 (0.96 to 4.77)g was infused to induce stable 50% reduction of stroke volume. The external pneumatic driver was synchronised to the animal’s ECG. We used an AMLAB instrument (Version 2.0 build 15, AMLAB Technologies, Australia) to control pumping parameters. Using different driving pressures (DrP, mmHg) and assist durations (AD, ms) cardiac function was checked when the DCC device assisted each heart beat (DCC on) and after DCC assist was ceased (DCC off) - see Table. II=4 Baseline HF rcc on ccc on KC off

DIP _

AD

182r38 226+76 _

ii0 210 _

SV (ml) 46 + 9 23+ 5 44+4 41+ 4 26+3

HR (bpm) 85 + 10 942 8 84+2 81 i 3 85+5

CO (Wmin) 3.85 + 0.56 2.13 -+ 0.51 3.65 + 0.35 3.34 + 0.35 2.19 + 0.24

BP (mmHg) 106 42 / 79+10 83+4/55?3 llOi6 / 59+9 112 k9 / 67+13 72+6/54?8

A novel prototype DCC device has been shown to support the heart for up to 2 million cycles without detectable damage. It is effective in restoring normal hemodynamics after acute iatrogemc HF. The device is easy to install, avoids thrombo-embolic risk and can provide biventricular support.

CHANGE IN PLASMA BRAIN NATRIURETIC PEPTIDE DURING EXERCISE IS AN IMPORTANT PREDICTOR OF SURVIVAL IN SYSTOLIC HEART FAILURE. JG cc Lam hbur * R Tr L Beckert, MG Nicholls. AM Richards. Cardioendocrine Research Group and Respiratory Department, Christchurch Hospital, Christchurch, New Zealand. We examined the effects of exercise on plasma atria1 (ANP) and brain (BNP) natriuretic peptide and the ammo terminal portions of their prohormones (NANP and NBNP) in 68 subjects with symptomatic left ventricular (LV) systolic dysfunction (mean + sd, LVEF 27+8%, NYHA II-III, age 35-85 years, 52 male, 48 ischaemic heart disease (IHD), 20 dilated cardiomyopathy). Ventilatory and gas exchange responses plus baseline and peak hormone levels were assessed during symptom limited cycle exercise (exercise time 362+125 set, achieving 84*14% of maximum heart rate). Peak V02 was 13.6k5.2 ml/kg/mm. Over 23i7 months of follow-up there were 15 deaths. Although overall mean ANP, BNP and NBNl’ increased with exercise (~~0.05 for all), BNP fell with exercise in those who died (-1.5?2.8pmol/l) differing (p=O.Oll) from an increase seen in survivors (4.lr2.8pmol/l). Those who died had more IHD (93 vs 64%, p=O.O2), lower LVEF (2127 vs 28+7%, p=O.OOl), higher baseline ANP (53230 vs37+23pmol/l, p=O.O33), BNP (52~20 vs 33*24pmol/l, p=O.O13) and NANP (2.521.0 vs 1.6*0.8pmol/l, p=O.O23). No other clinical, exercise or hormonal variable differed between survivors and non-survivors. In a multivariate model including LVEF, IHD and peak V02 only change in BNP with exercise (p=O.O03) added prognostic value for survival over LVEF (p
Heart,

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2001;

49th

10

EFFECTS OF HYPERINSULINAEMIA ON SKELETAL METABOLISM AND BLOOD FLOW IN PATIENTS WITH HEART FAILURE WA Parsonaee*, D Hetmanski & A Cowlev, Hospital, Nottingham, United Kingdom

MUSCLE CHRONIC University

Background: Chronic heart failure (CHF) is an insulin resistant, hyperinsulinaemic state in which abnormalities of skeletal muscle structure, metabolism and blood flow are known to occur. Insulin has profound effects on muscle metabolism and blood flow. Insulin resistance and hyperinsulinaemia have been linked to impaired exercise tolerance in patients with CHF but the mechanism of this phenomenon has not been studied directly. We sought to investigate the effect of hyperinsulinaemia on muscle blood flow and metabolism using a combination of the hyperinsulinaemic euglycaemic clamp and a forearm model of muscle metabolism. Methods: Ten male patients with stable chronic heart failure were studied on two occasions. Subjects performed a series of isometric handgrip exercises using ihe right hand at increasing workloads (5 seconds contraction, 5 seconds rest for 5 minutes) of 7,14 and Zlkg interspersed with rests of 12 minutes. One hour prior to the commencement of exercise the hyperinsulinaemic euglycaemic clamp was commenced with a constant weight adjusted insulin infusion to raise the subjects plasma insulin level to a steady state of -25OmU/l whilst maintaining euglycaemia at fasting levels using a variable infusion of 20% glucose. On the second occasion a saline placebo replaced the insulin infusion. The antecubital vein of the exercising forearm was cannulated in a retrograde fashion at the beginning of the study. Blood was sampled for assay of lactate, ammonia and blood gas before, immediately after and two minutes after each phase of exercise. Forearm skeletal muscle blood flow was measured at the end of each phase of exercise using venous occlusion plethysmography. Results are expressed as meanrstandard error and the two visits were compared using paired t-tests. Results: Hyperinsulinaemia led to a marked increase in skeletal muscle lactate production during exercise (Area under the curve 2.5OeO.50 vs. 1.48+0.45 units p=O.O2; Peak lactate 2.18?0.31 vs.1.63+0.24mmol/l p=O.Ol). Hyperinsulinaemia had no effect on ammonia production, oxygen extraction or forearm muscle blood flow Conclusion: Hyperinsulinaemia led to a marked increase in skeletal muscle lactate production in the absence of an increase in muscle blood flow or oxygen extraction. These results offer a rational mechanism for the observed relationship between insulin resistance and reduced exercise tolerance in patients with CHF. In this context manoeuvres that reduce insulin resistance merit further study in patients with CHF.

RELATIONSHIP BETWEEN POST-EXERCISE NONINVASIVE BIOIMPEDANCE HAEMODYNAMICS AND THE C-MINUTE WALK TEST IN ADVANCED HEART . # ,D,J,q i fi. &, t ,TYeo,,t,,D& FAILURE. a*tY. PM v tipaIlment of Cardiology, Concord Hospitalt. Concord. NSW: Department of Cardiology, St George Hospital’, Kogarah, NSW; Faculty of Health. University of Western Sydney’, NSW:

Faculty of Nursing, Univesity of Sydney!. NSW. Exercise haemodynatmcs and exercise tolerance may predict symptoms and prognosis in heart failure. The relationship between exercise tolerance and noninvasive haemodynamics is not known, particularly in heart failure patients who usually exercise at a gradual pace and do not reach high levels of exertion. We aimed to compare the haemodyttamics via bioimpedattce of heart failure patients before and after a submaximal exercise test to the results to the 6.mlnule (6-min) walk test to estimate their relationship and whether both tests need to be performed in hext failure evaluation. METHODS: Studied 41 patients. age.68flOyears. 85% male, Left VentricuIaT (LV) ejection fraclion 0.26fO.lS, New York HeaTt Association class 2.X 0.8 units Patients underwent 6. min walk tests with biotmpedance surface electrode haemodynamic tests before and after exercise. Linearregression correlation coefficients (r-values) are reported for haemcdynamic variablesvs6.tin walk time. RESULTS: HAEMODYNAMIC VARIABLE vs 6MIN WALK HEART RATE (bonts/mtn) BLOOD PRESSURE (mmH8) CARDIAC OUTPUT (Ilmln) SYSTEMIC VASCULAR RESISTANCE (dynes/cm/see-5) STROKE VOLUME (ml/bent) THORACIC FLUID CONTENT (ml) LEFT CARDIAC WORK (kb/mtn) VELOCITY INDEX (11000 set) PRE-EJECTION PERiOD (msee) LV EJECTION TIME (msec)

REST r-value 0 21 0.05 0.08 (SVR) 0 18 O.t8 0.02 0 05 0.15 0.16 0.36

POST-EX r-value 0.14 0.11 0 02 0.16

CHANGE

0.09 0.04 0.07 0.11 0.17 0.30

-0.09 +o 02 l 0.02 -0.04 +o.ot -0.06

r.VdUe

-0.07 +0.“6 -U.O6 +o “2

NO r-value was significant There was no predictive relationship between resting and postexercise haerwJynamlcs. There was no relationship between the results of the 6-mitt walk test and neither the resting nor post-exercise haetwdynamics CONCLUSIONS: The 6.min walk test assesses functional capacity whilst noninvasive

bioimpedmce haemcdynamics independently measures the cardiovascular response to reduced LV function in heart failure. They are not able to be substituted far the each other and theu results are not related.As they are not related the ability to augment the cardiovascular reserve may not predxt the functional capacity A combination of tests appear necessary to make an accurate haemndynamic andfunctional assessment of the severity of advanced heart failure

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A69

REDO SURGERY FOR PATIENTS WITH PROSTHETIC VALVE ENDOCARDIT1S.P.W. Grant*. D. Law, H.D. Wolfenden. G. Crannev. I? Tones. D.C. Newman Department of Cardiothoracic Surgery, The Prince of Wales Hospital, Randwick Sydney, New South Wales. INTRODUCTION Management of prosthetic valve endocarditis (PVE) remains a challenging problem where a multidisciplinary approach including antibiotic therapy, transoesophageal echocardiography (TOE) and redo surgery is required. We reviewed the preoperative findings, operative details and outcome in patients whom underwent surgery for PVE. METHOD Prospective 5 year review (1996 to 2000) of 11 consecutive patients with I’VE who underwent redo valve surgery. Endocarditis was defined as positive blood cultures or operative findings of infection such as vegetations and abscesses. Clinical. echocardioerauhic and operative details were analvsed. RESULTS Of the 11 patients with PVE, organisms identified were staph. epidemidis 1, staph. aureus 4 (1 MRSA), E. faecalis 2, strew mitis 1 and culture negative 3. Khmnns ‘for surgery were either haemodynamic (3 patientsj, sepsis (4 patients) or both sepsis and haemodynamic (4 patients); 7 patients required urgent surgery. Valves explanted were stented porcine (4), mechanical (5), stentless porcine (l), composite mechanical valve/graft (1). TOE was used for preoperative assessment in all 10 patients suspected of PVE. Findings included periprosthetic leak, mobile echodense masses and abscess formation. At operation only 2 patients had more cardiac invasion than expected from TOE. Valve deterioration on serial TOE was the indicator for urgent surgery in 2 patients. Operations required for I’VE were Redo AVR 8(1 combined with MV surgery), Redo MVR 2(1 combined with AV surgery) and Redo Bental using 2 homografts 1 patient. Patch reconstruction of the aortic root was required in 3 patients. All patients received at least 6 weeks of appropriate antibiotic therapy. 2 patients had long term postoperative therapy There was no operative mortality and only 1 late death from recurrent PVE. CONCLUSION Surgery for PVE can be performed with satisfactory results. The diagnosis of PVE remains difficult and TOE can be helpful in determining the extent of cardiac involvement. Surgery is often urgent and patients with I’VE should be evaluated promptly. ”

I

OPERATIVE RISKS ASSOCIATED WITH ISCHAEMIC MITRAL GITATION G Mathur’. D Law, S Rev. P Grant. H Wo1fenden.D G Crannev Department of Cardiology/ Cardiothoracic Surgery, Wales Hospital, Sydney

REGURNewman. Prince of

Ischaemic mitral regurgitation (MR) presents a dilemma for the surgeon in patients undergoing revascularization. Surgical correction of MR may not always be appropriate and the optimal surgical technique remains controversial. In this study results of surgical treatment of ischaemic MR were analysed retrospectively and predictors of post op mortality examined. Methods: From the surgical database between the years 1996 and 2000, 52 patients, mean age 70 (range 38-86) were identified as having ischaemic MR and underwent coronary artery bypass grafting (CABG) and/or mitral valve surgery (MVSx).Two patients had papillary muscle rupture. The MR was defined ischaemic, based on angiographic and echocardiographic findings. Results: Early post-operative mortality (<30days) associated with ischaemic MR was 15.4%. Univariate predictors of post-op mortality were preop severity of MR (p=mod =mod CABG

25

CABGlMVR CABG/MVrepair MVR’ Mvrepair *

13 8

0 5

18 7 14 0 13 9 1 2 6 3 4 1 0 4 2 2 1 0 2 0 MVR - Mitral valve replacement, ‘Patients with previous CABG,

11 4 5 2 2

A70

49th

Annual

Scientific

Meeting

STAR PROCEDURE - SURGICAL USE TION FOR THE CURE OF ATRIAL RB Chard , G Nunn , DT Guv , SI’ Thomas of Cardiology and Cardiothoracic Surgery,

of CSANZ

OF RADIOFREQUENCY ABLAFIBRILLATION IA Nicholson *z , AC Bovd , DL Ross Departments Westmead Hospital, Sydney

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2001;

10

MITRAL VALVE REPAIR IN PATIENTS WITH DEGENERATIVE MITRAL REGURGITATION AND LEFT VENTRICULAR IMPAIRMENT. my”. D.Law. G.Mathur. P.C&&. H.Wolfenden. D.Newman, G.Cranney. Prince of Wales Hospital, Sydney, NSW

Objective: The Star procedure utilizes a simple radial pattern of surgically placed radiofrequency lesions to cure atria1 fibrillation in most patients and preserve atria1 transit function. We aim to analyse the results of 40 patients who have undergone the Star procedure between July 1995 and Dee 2000. The surgical procedure will be described. Methods: All patients undergo pre-operative assessment to determine duration and pattern of AF and echocardiographic assessment of atria1 transit function. Patients had either paroxysmal or chronic AF. All post-operative patients are then followed with El’ study at 6 months to determine lesion integrity and to attempt arrhythmia induction. Results: Twenty seven patients ( 67%) had concomitant procedures, predominantly valve related. Thirteen patients ( 33%) were lone fibrillators. Mean cross-clamp time was 110 minutes. Twenty nine patients ( 73%) were in sinus rhythm at discharge from hospital. A number of patients demonstrated Atria1 flutter early , which reverted over time or was cured at follow-up El’ study using further RF ablation. Patients have a significant improvement in symptoms ( p = 0.008) and anti-arrhythmic medication requirement (p=O.O06). Conclusion: The Star procedure cures Atria1 Fibrillation in the majority of patients and significantly improves symptoms. Post-operative El’ study is an essential tool in the evolution of this surgical technique.

Introduction: The optimal timing for surgery in patients with myxomatous degenerative mitral regurgitation remains controversial. Mitral valve repair with preservation of the subvalvular apparatus preserves left ventricular (LV) function in comparison to valve replacement, however deterioration in function may still occur following valve repair, and is difficult to predict. Those patients with significant impairment of LV function preoperatively are thought to fall into a poor prognostic category. The aim of this study is to present the experience in our institution of mitral valve repair in patients with significant LV impairment and degenerative mitral regurgitation. Method: Over a three and a half year period, (June 1997 - December 2000), 109 patients with degenerative mitral valve regurgitation, and no significant coronary disease, underwent a mitral repair procedure. A retrospective analysis of this population was undertaken, and those patients with at least moderate impairment of LV systolic function on echocardiography, and ejection fractions of less than 40% on ventriculography were specifically reviewed. Results: Eight patients were identified as having degenerative mitral regurgitation, and at least moderate impairment of LV systolic function. Six patients were male and two female, with an average age of 60.0 years, (range 47-74). All patients were stable on optimal medical therapy, with symptoms ranging from NYHA class II to IV. All eight patients underwent mitral valve reconstruction and insertion of a Duran annuloplasty ring, with improvement of at least one NYHA class at six weeks post surgery. After a mean follow up period of 19 months (range 3 to 44) all patients remain alive and well, with none having required rehospitalisation. Conclusion: Our experience suggests that even in patients with moderate or severe LV impairment and degenerative myxomatous mitral regurgitation, with appropriate post-operative care, valve repair can be successfully undertaken.

AORTIC VALVE REPLACEMENT IMPROVES SURVIVAL IN PATIENTS UNDERGOING CORONARY ARTERY BYPASS SURGERY WITH MILD TO MODERATE AORTIC VALVE STENOSIS KW B&ban, n Pereira’. M Bashir. BW Lvtle. ID Thomas. MT Garcia. The Cleveland Clinic Foundation, Cleveland, Ohio, USA.

TISSUE TRICUSPID VALVE REPLACEMENT IS SAFE AND EFFECTIVE FOR CARCINOID VALVOPATHY. M Binnekamo*. D.Rees #, B. Weiss. G. Fermanis. D.Horton. Departments of Cardiology# and Cardiothoracic Surgery, St George Hospital, Sydney, Australia.

Objectives: Aortic valve replacement (AVR) for mild or moderate aortic stenosis (AS) at the time of coronary bypass surgery (CABG) remains controversial. We sought to assess if there is a survival benefit for patients (pts) with mild or moderate AS who receive AVR at the time of CABG. Methods: Between 1985 to 1995 we identified all pts requiring coronary bypass with aortic stenosis for whom pre-operative echocardiography was available. Patients with severe AS (left ventricular ejection fraction (LVEF) 2 50% and mean gradient > 35mmHg, or LVEF < 50% and aortic valve area 2 1.0 cm2) were excluded. Clinical echocardiographic, cardiac catheterization and surgical variables were analyzed and pts followed for a mean of 6.5 years after the operation. Results: There were 129 pts (age = 68+8 years, 92 males) who underwent CABG alone and 82 pts (age = 69+8 years, 68 males) who underwent CABG with AVR. Survival by Kaplan-Meier analysis is shown for CABG alone versus CABG-AVR groups. There was a similar in-hospital mortalI.0 ity: 3.1 vs 3.7% respectively. However, in comparison to the CABG group, the CABG-AVR group had significantly improved long-term m survival (p
Chemotherapy has resulted in dramatic improvement in survival for metastatic carcinoid tumours and seen the emergence of cardiac carcinoid syndrome (CCS) as a major cause of morbidity. Characteristic endocardial lesions result in valvular retraction and fibrosis with severe tricuspid regurgitation and right sided heart failure that precludes aggressive hepatic surgical resection. Improved cardiac surgical techniques have allowed the insertion of tissue prostheses in the tricuspid position without problems with infection and thrombosis seen with earlier mechanical prostheses. We are prospectively evaluating tissue tricuspid valve replacement (TTVR) for patients with medically refractory CCS. 3 patients underwent ‘ITVR with the Mosaic prosthesis between 1999 and 2000. Detailed pre-operative right heart catheterisation was undertaken to exclude significant irreversible pulmonary hypertension or pulmonary valve stenosis and coagulopathy was identified and corrected if present. The mean age was 57 * 8 years, with one female patient. 1 patient had undergone closure of an atria1 septal defect in childhood and surgery was complicated by adhesions and a left sided superior vena cava. The average length of stay was 10.3 f 4 days, with one early re-operation for bleeding related to coagulopathy. The other cases did not experience bleeding that differed significantly from standard valve replacement surgery. There was no in hospital mortality, however one patient died 4 months postoperatively during attempted hepatic resection. The surviving patients had significant improvements in ascites, weight, right heart failure and life quality scores allowing reductions in medications in both cases. TTVR is a safe and effective treatment in selected patients with medically refractory CCS.

Heart,

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49th Annual

2001; 10

Scientific

Meeting

of CSANZ

A71

ACCELERATED ASSESSMENT OF CHEST PAIN IN INTERMEDIATE RISK PATIENTS: RECLASSIFICATION USING THE NEW GUIDELINES. C.N. Aronev’. H. Dunlevie. T.H.N. B&t. Cardiac Unit, Prince Charles Hospital, Brisbane, Queensland.

TIME COURSE OF INFLAMMATORY MARKERS IN PATIENTS WITH CHEST PAIN AND ACUTE CORONARY SYNDROMES. SA Hope*. HMQ Farououe. SG Worthlev, TC Phmkett. N Balazs. IT Meredith. Cardiovascular Research Centre, Monash University, Monash Medical Centre, Melbourne.

Patients presenting with chest pain and intermediate risk features should be evaluated (Management Guidelines Unstable Angina 2000) by observation for at least 6 hours followed by serum troponin estimation and in those with no evidence of ischemia, exercise stress testing (EST). Patients with negative results are reclassified as low risk (LR) and may be discharged. Patients with evidence of &hernia are reclassified as high risk (HR) and remain for further investigation and treatment. This strategy may improve risk stratification and resource utilisation. Methods: 384 “intermediate risk” patients were evaluated using the “accelerated chest pain protocol” over a 10 month period. Telephone follow-up was performed in all patients at 30 days. Results: 60% of patients were reclassified as LR (average length of stay: 14 hours) and discharged for follow-up by local doctor (63%) or cardiologist (37%). 4 LR patients were readmitted and found to have non-cardiac pain following further investigation. No LR had an adverse event (death or MI) at 30 days. 40% of patients were reclassified as HR. Reasons for reclassification to HR included: 44 patients with recurrent chest pain, 13 with new ECG changes during observation, 12 with a positive serum troponin at 6-8 hours (which had been normal at baseline), and 19 patients with a positive EST. Of patients with a positive EST, 64% had coronary artery disease confirmed at coronary angiography (CA). 30 HR patients underwent CA which confirmed coronary disease in 26 (8 with Left Main or 3 vessel disease), of whom 12 were revascularised (6-percutaneous intervention, 6-bypass surgery); all were alive at 30 days. After initiation of the protocol there was a trend to reduced length of stay and health care costs for all patients presenting with chest pain. The protocol is considered self-funding and will be continued long-term. Conclusion: The accelerated chest pain protocol led to timely and accurate risk assessment and improved resource utilisation.

There is substantial evidence for the role played by inflammation in the development and progression of atherosclerosis. Cellular adhesion molecules are intimately involved in this process. Expression of adhesion molecules is induced by activation of platelets and endothelial cells and plasma levels are elevated in patients with conventional risk factors for coronary artery disease, and following unstable coronary events. We sought to characterize the time course of expression of P-selectin, E-selectin, VCAM-1, ICAM-1, Interleukin-6 (IL-6) and C reactive protein (CRP) in the 24 hours after development of chest pain secondary to acute myocardial infarction (MI) or unstable angina (UA) and to compare this with pain of non-coronary aetiology (NC). Blood was obtained from 57 patients presenting with chest pain, 14 with MI, 24 UA and 19 NC, within 4 hours of the onset of pain, with additional samples 6-8 hours later in all groups and 12-24 hours later in a subgroup of patients with MI or UA. Patients with a pm-existing diagnosis of an inflammatory or malignant disease were excluded. Mean ages were 60.3 years (MI), 63.5 years (UA) and 54.4 years (NC). Gender distribution was skewed across the groups with more women in the NC group, however gender did not influence inflammatory marker levels. Risk factor profiles were similar in all groups. Admission levels of markers were as follows: P-selectin 166ug/L (51-307) (median (range)), E-selectin 53&L (20-150), VCAM-1 379pg/L (183-738), ICAM268.7 pg/L (15s448), IL-6 ~5 rig/L (~5-871) and CRP 2.1 mg/L (<0.5-10.2). P-selectin levels at admission were unrelated to the time between onset of pain and blood sampling. No significant changes occurred over time in any of the 3 groups in any marker, and with the exception of P-selectin levels at admission which were slightly lower in the UA group compared with NC (pcO.O5), no differences were demonstrated in any of the markers assayed between any of the groups at any time point. No association was demonstrated with conventional risk factors for coronary artery disease, nor with peak creatine kinase levels in the MI group in this relatively small number of patients. The lack of change in the levels of inflammatory markers over the 24 hours following the onset of chest pain suggests that the timing of blood sampling may not be critical. Thus in studies assessing the prognostic significance of these markers following an acute coronary syndrome blood could be obtained at any time during the first 24 hours.

MANAGEMENT OF UNSTABLE ANGINA AND NON ST-ELEVATION MYOCARDIAL INFARCTION IN NEW ZEALAND: DO CARDIOLOGISTS DO IT BETTER? PI Conaelenr. C Sebastianz. C lavaraman~. A Abraha&, C Nunnl. G Devlinl Departments of Cardiology and General Medicine, Waikato’ and Taranaki2 Hospitals, New Zealand. Background: In New Zealand, a large proportion of patients with acute coronary syndromes (ACS) are managed by general physicians. Evidence however suggests that patient care is improved by subspecialisation. Methods: A retrospective study of the management of ACS at Waikato Hospital (W) and Taranaki Base Hospital (T). At W, the management of all ACS is specialist based with ready access to invasive cardiac procedures. General physicians manage the majority of patients at T. Results: A total of 301 consecutive patients, with a diagnosis of Unstable Angina or Myocardial Infarction, without ST elevation, admitted to W (n=144), and T (n=157). Mean age 68 years, 54% male. No significant difference was noted in risk factors or medications at discharge. Patients in W were more likely to undergo inpatient risk stratification, intervention and subsequent revascularisation with a shorter stay noted (median 4 v 5 days). At 6 months readmission rates were similar with a trend noted to reduced mortalitv in W. Catheterisation I’TCA CABG I’ts undergomg Cath, ETT, Echo or Nuclear Scan Readmission Revascularisation Mortality

Taranaki Base Hospital (n=157) 20 (12.7%) 4 (2.6%) 6 (3.8%) 72 (45.9%)

Waikato Hospital bl=144) 44 (30.6%) 14 (9.7”/“) 11 (7.6%) 94 (65.3%)

35 (22.3%) 1 (0.6%) 21 (13.4%)

36 (25.0%) 10 (7%) 14 (9.8%)

P= 0.0002 0.01 0.0008

NS

Conclusions: Direct admission with an ACS to cardioloev services results in more frequent revascularisation, shorter hospital stay ar$ a trend to reduced mortality at 6 months but similar readmission rates.

MANAGEMENT OF HIGH-RISK UNSTABLE ANGINA AND NON-ST ELEVATION MYOCARDIAL INFARCTION: VARIATIONS IN PRACTICE. FINDINGS FROM THE GLOBAL REGISTRY OF ACUTE CORONARY EVENTS (GRACE). D Brieeer*. S Heald. G Devlin. I Elliott, J Lefkovits. K.A.A. Fox, for the GRACE Investigators. Concord Hospital, Sydney, Australia, Waikato Hospital, NZ, Christchurch Hospital NZ, Royal Melbourne Hospital, Australia, The Royal Infirmary of Edinburgh, Edinburgh, Scotland, UK. GRACE is an international prospective registry of of acute coronary syndromes. 9251 patients with wave MI by discharge diagnosis were recruited Mean age was 66 years, 36% female, 24% diabetic, All values oresented as Dercentaees (n=9251)

management and outcomes unstable angina or non-Qin 100 sites. (14 countries). 82% prior MI or angina.

+Cath -C&h lab lab US ANZ EUR AB In-hospital PC1 28 4” 35 16 25 23” GP IIb/IIkl 15 3** 30 6 11 7** 39” LMWH 44 54’ 17 65 61 Aspinn 90 91 91 88 89 95” Discharge ACE 46 56” 43 47 53 48” 40” 57 22” Statin 45 53 44 AP/AGt 92 91 90 90 94 91 (+/-, with or without cath lab; ANZ, Australia, Nnu Zealand; AB, Argentina, Brazil; EUR. Europe; US, United States and Canuda. tAntipfntelet or anticoagulant ‘l’4l.05, “P
Despite consistency of certain pharmacological treatments (e.g. aspirin), marked variations were observed in the use of PCI, IIb/lIIa inhibitors and low-molecular-weight heparins (LMWHs) and use of statins on discharge. The use of PC1 and of IIb/lIIa inhibitors related most closely to the presence of on-site catheterization laboratory facilities and higher use was seen in the US than elsewhere. Further insight into this variation will emerge as data from GRACE continue to be collected.

A72

49th Annual

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of CSANZ

VENTRICULAR FIBRILLATION COMPLICATING ACUTE MYOCARDIAL INFARCTION: NEUROHORMONAL STATUS, VENTRICULAR IMAGING AND CLINICAL OUTCOMES. A.M.Richards*. I.C. Miller, J.G. Lainchburv, I.M. Elliott, T.G. Yandle. I.G.Turner. M.G.Nicholls. C.Framuton.. Christchurch Cardioendocrine Research Group, Christchurch School of Medicine, and Departments of Cardiology and Nuclear Medicine, Christchurch Hospital, Christchurch, New Zealand. Neurohonnones, LV function and outcomes were documented l-4 days and again 3-5 months post-acute myocardial infarction (AMI) in 1,031 patients. In 103 cases of AM1 complicated by ventricular fibrillation (VF), peak creatine kinase and Troponin T levels were higher (3525+353 vs 1987+57u/L; p
Heart,

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and Circulation

2001; 10

EXTENSIBILITY OF THE AORTIC ANNULUS AND ROOT FOLLOWING INSERTION OF THE CRYOLIFE-O’BRIEN, STENTLESS PORCINE AORTIC XENOGRAFT - A 3-DIMENSIONAL ECHOCARDIOGRAPHIC STUDY. A. Lance. I? Palka. D.1. Burstow* M.F. O’Brien. The Prince Charles Hospital, Brisbane, Australia. BACKGROUND Restoring the dynamic changes of the aortic root during a cardiac cycle with stentless aortic valve bioprostheses may have a favourable effect on durability. The Cryolife-O’Brien stentless aortic valve is composite, with no dacron support, and is implanted in the supra-annular position which should allow the extensibility of the native aortic annulus to be preserved. Imaging the human aortic root by 3-dimensional (3D) echocardiography now allows measurement of both dimensional and volume changes throughout the cardiac cycle. METHODS Nine randomly selected patients (age 74 r3 years, 2 female) were studied at 3 to 6 months after AVR implantation using 3D echocardiography. In each patient, 3D reconstruction of the aortic root distal to the semilunar attachments of the cusps was performed. The changes in aortic root volume were calculated throughout a cardiac cycle. RESULTS Significant changes in aortic root volume were observed in all patients with the greatest aortic annulus in early systole (Fig 1A below) and the smallest in late diastole (Fig 1B below) (17*6 ml ns. 1325 ml, p< 0.05; respectively). The absolute difference between the maximum and the minmum aortic root volume was 25+14% (range 27% to 39%). CONCLUSIONS The observed changes in aortic root volume confirm that aortic root and annulus extensibility is preserved following insertion of the Cryolife-O’[email protected] AVR.

DOES ANTIARRHYTHMIC TREATMENT ALTER OUTCOME IN ATRIAL FIBRILLATION COMPLICATING ACUTE MYOCARDIAL INFARCTION? THE GUSTO-III BXPERIENCE. CK [email protected]+. EM Ohman, HD White for the GUSTO-III investieators. Cardiology, Green Lane Hospital, Auckland, New Zealand

GEOMETRIC ENDO-VENTRICULAR REPAIR OF ANTERIOR LEFT VENTRICULAR SCARS IMPROVES FUNCTIONAL STATUS OF PATIENTS WITH HEART FAILURE &man 1.’ Hare DL. Hata M. Storer M, Buxton BF Department of Cardiac Surgery, Austin & Repatriation Medical Centre, Heidelberg, Vie.

We prospectively investigated whether the use of antiarrhythmic agents and electrical cardioversion would alter mortality in 1,138 patients with atria1 fibrillation complicating acute myocardial infarction (MI) in the Global Use of Strategies To Open occluded coronary arteries (GUSTO-III) trial. The occurrence of atria1 fibrillation after administration of thrombolytic therapy for acute myocardial infarction can be secondary to some post-MI cornplications but independently portends a worse prognosis. Whether treatment of atria1 fibrillation can affect mortality is unknown. In the 1,138 patients with atria1 fibrillation from the GUSTO-III trial, 317 (28%) received antiarrhythmic therapies: class I antiarrhythmic agents were administered in 12%, sotalol in 5%, and amiodarone in 15%; electrical cardioversion was attempted in 116 patients (10%). Sinus rhythm was restored in 72% of patients receiving class I antiarrhythmic agents, 67% of those receiving sotalol, 79% of those receiving amiodarone, and 64% of those who had electrical cardioversion. After adjusting for baseline characteristics and the post-MI complications before development of atria1 fibrillation, there was no difference among the treatment groups in the incidence of having sinus rhythm at the time of discharge or before deterioration to hospital death. However, the use of class I antiarrhythmic drugs or sotalol was associated with a lower unadjusted 30-day and one-year mortality. After adjusting for baseline factors and pre-atria1 fibrillation complications, the odds ratios were, respectively, 0.42 (CI 0.19 to 0.89) and 0.31 (CI 0.07 to 1.32) for 30day mortality, and 0.58 (CI 0.33 to 1.04) and 0.31 (CI 0.09 to 1.02) for one-year mortality. In contrast, there was no association between the use of amiodarone or electrical cardioversion and 30-day or one-year mortality. There is a lower mortality associated with the use of class I antiarrhythmic agents or sotalol in managing atria1 fibrillation after acute MI. Randomized trials of these agents for the treatment of atria1 fibrillation in the early setting of acute MI are urgently needed to define the optimal treatment strategies.

Large ventricular scars are known to be associated with heart role of left ventricular reconstructive surgery in these patients, lished is yet to achieve widespread acceptance.

failure. The while estab-

Ninety one patients underwent left ventricular reconstruction using the Geometric Endo-ventricular patch repair technique between Ott 1997 and Jan 2001 of large anterior ventricular scars. Median NYHA class pre-operatively was III, while the mean preoperative left ventricular ejection fraction (LVWF) was 26%. These patients underwent coronary artery surgery and other adjunctive procedures, as indicated. There were 2 peri-operative cardiac deaths (2.1%), and 2 peri-operative neurological deaths (2.1%). There were 2 early deaths due to multi-organ failure in the setting of emergency surgery for cardiogenic shock, for a total early mortality of 6.5%. There were 2 late deaths (2.3%) and 2 episodes of late ventricular tachycardia (2.3% requiring insertion of defibrillators. Sixty three patients (76%) were in NYHA Class I at a mean follow up of 410 days. Mean post-operative LVEF was 37% (~~0.305). Geometric endo-ventricular repair of large anterior ventricular scars can be performed safely, with an encouraging functional improvement in patients with heart failure.

Heart,

Lung

and

Circulation

2001;

49th

10

CHRONIC ANIMAL IMPLANTS OF THE VENTRASSIST ROTARY PUMP CARDIAC ASSIST DEVICE FL Rosenfeld~. DS Esmore. T A Smith. J Anderson, P Awe. G Tan&v. N lames. T Bee- I Woodard. P Watterson. Cardiothoracic Surgery Dept.; Cardiac Surgical Research Unit, Alfred Hospital; Dept of Surgery Monash University, Melbourne; Micromedical Industries, Sydney. Background: Important drawbacks of the current generation of mechanical cardiac assist devices are valves and bearings, both of which are subject to wear and cause haemolysis and thrombosis. The ideal mechanical cardiac assist device would be long-lasting, and non-traumatic to blood. The VentrAssist rotary pump, is a novel, compact, implantable cardiac assist device developed by the University of Technology Sydney and Micromedical Industries Limited. The pump, made of titanium alloy contains a four lobed rotor, hydraulically suspended in the blood path without conventional bearings. The rotor is driven at 1500 to 3000 ‘pm by electromagnets built into the pump housing and pumps blood at 2 to 10 L/min. In bench tests using human blood the pump produced minimal haemolyis. Methods: Ten Implants were performed in sheep with the pump connected as a left ventricular assist device between the left ventricular apex and the thoracic aorta. Results: In 5 animals planned survival was gradually extended from 48 hours to 4 weeks. Five animals died, one from cannula rupture and 3 from non-pump-related complications The pump performed well with flows up to 6 L/min, without thrombosis or observable mechanical wear. Post surgical plasma free haemoglobin levels were 5 10 mg/dl indicating less haemolysis than the current generation of centrifugal pumps used for cardiopulmonary bypass. Ongoing design improvements concern the sensing of pump output and reducing overall pump size Conclusions: The VentrAssist pump shows promise as a long-term cardiac assist device. Trials of the final clinical design are planned in sheep lasting six months and human application is scheduled for 2001.

CLINICAL EXPERIENCE WITH THORACIC AORTIC ANEURYSM AND AORTIC DISSECTION. C.C. Yu* and M.T.West. Department of Medicine Prince Charles Hospital, Brisbane. Thoracic aortic aneurysm (AA) and dissection (AD) are associated with high mortality and morbidity. A retrospective survey was carried out to define current risk factors and management outcomes. The case notes of all subjects admitted to the Prince Charles Hospital with a discharge diagnosis of AA or AD between December 1992 and May 1999 were reviewed using criteria derived from a review of current literature and a pilot sample of cases. Details derived from the review of case notes were tabulated. The review was based on details of 294 subjects with AA and AD. There were 180 patients with AA, 120 with AD, 39 with thoraco-abdominal aneurysm and 21 with both AD and thoraco-abdominal aneurysm. The median age was 66 yrs (range 14-89 y’s). 61% were males. Risk factors included basal metabolic index >25kg/m2 in 45%, hypertension in 76%, cigarette smoking in 68%, family history in 20%, and ischaemic heart disease in 27%, cerebrovascular disease in 16% and peripheral vascular disease in 6%. Ascending AA occurred in over 60% of cases, most involving the aortic root. The majority of subjects with AA or AD were symptomatic. Most aneurysms were diagnosed using transoesophageal echocardiogram. On admission 22 of 180 patients with thoracic aortic aneurysm had a rupture. In half of these the size was greater than Scm. 10 subjects survived rupture. For type A dissection, 48 patients were managed conservatively with 6 deaths within 2 years. 70% of patient with type B dissection were assigned to medical therapy. Of 7 patients who underwent surgical repair for the type B dissection 3 survived to 2001. AA and AD continue to be associated with high mortality. Most are symptomatic at first diagnosis. Early diagnosis using transoesophageal echocardiogram is probably a prerequisite for successful management.

Annual

Scientific

Meeting

A73

of CSANZ

ECHO/DOPPLER EVALUATION OF 140 NORMAL GRAFTS: COMPARISON WITH NEW GENERATION MECHANICAL AND STENTLESS XENOGRAFT D. Burstow’. 1. retch, I. Smith, M. O’Brien. The Prince Brisbane, Qld.

AORTIC ALLOBILEAFLET PROSTHESES. Charles Hospital,

Background: A major advantage of the normal aortic allograft prosthesis (AAllo) is said to be superior haemodynamic performance. Recently, new generation mechanical and tissue prostheses with improved haemodynamics have become available. The aim of the current study was to establish the normal values for Doppler haemodynamic parameters for AAllo and compare the findings with previously obtained data for the ATS mechanical and Cry“life-O’Brien (CLOB) stentless xenograft prostheses. Method: Utilizing our data base, 140 patients were identified who had undergone echo/Doppler evaluation less than 12 months following AAllo implantation and had 5 grade ‘/4 aortic regurgitation (AR). Results: A selection of data is provided below and is presented as median and interquartile ranges. The Mann-Whitney test was used for comparison of Doppler parameters. AAllo size V,m/s

Zlmm 1.8

22mm 2.0

23mm 1.8

24mm 1.6

25mm 1.5

1.4-2.8

1.7-2.3

1.6-1.9

1.3-1.9

1.3-1.7

Mean Grad

7.0

7.0

6.0

5.0

5.0

4.5-10.3

5.5-8.0

4.0-8.0

4.0-8.0

4.0-6.0

DPI

0.64

0.60

0.68

0.67

0.68

.43-.81

.55-.70

.55-.81

.57-.82

.59-.75

EOA(cm*)

2.2

2.3

2.7

3.1

3.2

1.5-2.2

2.0-2.9

2.2-3.1

2.4-3.5

2.9-3.5

V,= peak aortic velocity IO_

DPI = LVOT velocity/ “Fi

I

IlO.

27mm 1.5 1.4-1.7 5.0 4.0-6.8 0.65 .54-.75

3.5 2 74.1

V, EOA = effective orifice area. EOA

I

** = p
PAPILLARY FIBROELASTOMA: A RARE BUT POTENTIALLY TREATABLE CAUSE OF EMBOLIC STROKE. W Saw’. S Nicholls. G Trim, K Pant. D Thomson, C Hwhes. S Mitchell, and I Leitch. John Hunter Hospital. Newcastle. New South Wales, Royal Prince Alfred Hospital. Sydney. New South Wales. Background: Papillary fibroelastomas (PF) are rare benign tumours and are seldom diagnosed during life. We report a series of three cases, two had recurrent embolic events, and one was diagnosed incidentally.

WSex Presentation Site

Structural heart disease Surgical treatment Anticoagulation Recurrent event

Case 1 31 Male Multiple cerebral and splenic embolism Atrial aspect of mitral valve

Case 2 48 Male Multiple cerebral embolism Atria1 aspect of Mitral valve

Nil

NII

Resection and repair of mitral valve 12 months Nil

Resection and repair of mitral valve 12 months Nil

Case 3 56 Male incidental Right ventricular aspect of interventricular septum Small membranous VSD Resection and repair of VSD Nil

Discussion: PF are the third most common cause of primary cardiac tumours and 80% of them are found on valvular endothelium. They can occur at the site of high velocity jets. A review of literature reveals 100 cases of PF diagnosed in life. Thromboembolism is the most common complication. Surgical removal of tumour is recommended regardless of symptoms because of potential for embolism. In our series no patient required valve replacement. In one reported series, 90% of patients were treated with excision and 10% required valve replacement. It is common practice to anti-coagulate patients after operation but literature provides no firm evidence regarding duration of anticoagulation. It seems reasonable to discontinue warfarin after a period of 6-12 months. Conclusion: Papillary fibroelastomas are a rare but potentially treatable cause of cardiac emboli. Prompt identification allows for surgical excision, which generally is curative.

A74

49th Annual

Scientific

Meeting

of CSANZ

Heart,

TITLE: ACUTE CARDIOGENIC PULMONARY OEDEMA INCREASES CIRCULATING SURFACTANT PROTEIN A AND B LEVELS CG Pasauale*. AD Bersten. IR Dovle. PE Avlward. R Grant, LF Amolda, Cardiac, Critical Care and Human Physiology Departments, Flinders Medical Centre, Adelaide, SA, Australia RATIONALE: In acute cardiogenic pulmonary oedema (APO) increased extravascular lung water (EVLW) is thought to reflect an increase in pulmonary microvascular pressure (p,,) rather than increased alveolocapillary permeability. However, increased q,, could damage the alveolocapillary membrane. To investigate alveolocapdlary permeability in APO we measured the leakage of surfactant proteins A and B (SPA -B) from the alveoli into the circulation. METHODS: Venous blood was collected on days 0 (presentation), 1,3,7 and 14 for SP-A and -B assay (ELISA) from 18 consecutive patients with APO (age 74+3, mean&EM). A clinical pulmonary oedema score based on the Killip class-scoring system was documented at the same time points. Chest X-rays were assessed for EVLW using a validated scoring system and arterial blood gas analysis performed. RESULTS: Clinical, oxygenation and radiographic improvement following presentation were rapid. However, plasma SF-B rose to a peak at day 3 and then fell to below presentation level by day 14. DAY 0 1 3 7 14 SP-A x 551r42 528i44 543+33 537c45 426~36~ SP-B x 7824~648 10158~1608 10470+1547’+ 9556t1459 6277+9x+ Pulmonary # 2.7k202 1.9*.17= 1.4+.12= 1.2k.11 Oedema Score 6*0 PaOZ/FiOZ 213r23 350*2st CXR EVLW 50*5 13*3t (Repeated measures ANOVAP
CONCLUSIONS: Despite clinical evidence of resolution of elevation of SF-B suggests that increased permeability pathophysiology of APO, and this is slow to resolve.

USE OF A HEART HEART FAILURE K Inelev, SF Wrieht, sitv of Auckland.

Background: Heart failure (HF) has a significant effect on both quality of life and personal morbidity. Self-management strategies including HF diaries, self-adjustment of diuretics and weight monitoring are recommended in NZ HF guidelines. However, little is known of the uptake of such strategies or the determinants of compliance. This study reports the use of a heart failure diary by patients in an integrated HF management programme. Methods: The patients in this study were a cohort of HF patients enrolled in a clinic-based HF management programme (Auckland Heart Failure Management Study). All patients were given a HF diary containing a personalised medication list, a compliance record and diary pages for recording weights. Patients were encouraged to weigh themselves daily, and principles regarding self-adjustment of diuretic were taught. Diary use was individualised according to patient requirements. Principles of self-management and daily weighs were also covered at three 90-minute education sessions. Diaries returned to the HF clinic over the first 3 months were analysed for this study. Results: 100 patients were included in the management programme. Mean age 73yrs (range 34 to 92), 36 were female, 29 lived alone, and 34 patients had one or more previous admissions with HF. 90 patients attended an initial HF clinic visit within a median of 11 days after hospital discharge. 76 patients patients returned their diary to HF clinic. Of the 71 patients who recorded their weight in the diary, 56 (79%) recorded their weight more than once a week. Of the 15 oatients who recorded their weieht less than once oer week. 10 did not have ” 1 L scales at home. Mortality and HF cliic attendance is shown below: Did not use diary 24 11 (46%) 9 (38%) 1.5 (1.7)

and Circulation

2001;

10

EFFECT OF COMPREHENSIVE MANAGEMENT ON FUNCTIONAL STATUS IN PATIENTS REFERRED TO AN ADVANCED HEART FAILURE SERVICE. D. Green. *A. Maiorana. A.Wiltshire. G. O’Driscoll. R. Tavlor: Department of Human Movement and Exercise Science, The University of WA and Department of Cardiology and Cardiac Transplant Unit, Royal Perth Hospital, Perth Western Australia. Specialist heart failure (HF) clinics offering comprehensive care may optimise patient management. We evaluated changes in functional status following 6 and 12 months of comprehensive care, which included exercise training. Results are compared with data collected in a prospective trial of HF patients involving exercise training alone and a non-exercise control period. Retrospective analysis was conducted on patients referred to the Royal Perth Hospital Advanced Heart Failure Service; age 47&3 years (mean+SE), ejection fraction 32+6%, NYHA class I-IV Peak oxygen consumption (VOz peak) and muscle strength (sum of 3 maximum voluntary contractions) were assessed at baseline and following 6 (n=l9) and 12 months (n=ll). Comprehensive treatment involved optimising medical therapy, close nursing support and supervised exercise 2-3 times/week. VO, peak increased after 6 (22.Ok1.7 vs 19.8+1.4ml/kg/min, P
of APO, the pattern contributes to the

FAILURE PATIENT DIARY IN THE AUCKLAND MANAGEMENT STUDY. S Muncaste?. HI Walsh. N Sharoe and RN Douehtv. Dept of Medicine, Univer-

N No. died in 12 months No. with no HF clinic visits Mean no. HF clinic visits

Lung

Used diary 76 8 (10.5%) 1 (1.3%) 4.2 (1.6)

‘D
CALCULATING VO,PEAK BY ADJUSTMENT FOR LEAN BODY MASS IN PATIENTS WITH CHRONIC HEART FAILURE D. Green, *A. Maiorana, T. Kuipers. G. O’Driscoll. R. Tavlor. Department of Human Movement and Exercise Science, The Universitv of WA and Department of Cardiology and Cardiac Transplant Unit, Royal @erth Hospital, Perth Western Australia: Peak oxygen consumption (VOgeak), in ml.kg-‘.min-‘, is commonly used to stratify patients for cardiac transplantation. Osman et al. recently proposed that VOgeak, adjusted to lean body mass (LBM), increases the prognostic value of exercise testing because fat mass is relatively metabolically inactive. However existing equations used to calculate LBM from skinfold thickness are based on indirect measures of body composition and assumptions that are not specific to chronic heart failure (CHF) patients. In this study, LBM calculated using existing skiiold equations was compared with that derived from dual-energy X-ray absorptiometry (DEXA), to determine whether VOgeak stratification differed using the two protocols. Twenty-three subjects with CHF were recruited, age=55.1*2.3 years (mean&E); ejection fraction=27+2%; V0,peak=18.8~1.3ml.kg.~1min~‘; NYHA class I-III. Subjects underwent anthropometric assessment including DEXA, with weight, height and skinfolds also measured. VOzpeak was assessed during graded treadmill exercise. Discriminate factors of 14ml.kg.min-’ and 19ml.kgLBM:‘min-’ were employed to stratify patients according to total body mass (TBM) and LBM respectively. LBM calculated using skinfold equations was higher than with DEXA (65.2+2.4kg vs 58.6+2.0kg,y<0.001). Consequently, LBM adjuste VOGeak was higher based on DEXA versus skinfold equations (27.321.8 vs 24.8+1.7ml.kgLBM:‘min-‘;p
Heart, Lung and Circulation

49th Annual Scientific Meeting of CSANZ

2001; 10

SINGLE CENTRE EXPERIENCE WITH BI-VENTRICULAR PACING IN PATIENTS WITH SEVERE HEART FAILURE D Hoist’. G TooPood. A Brouehton. I’ Berein. D Kave. H Krum. A Aeearwal. D Prior. M Richardson Heart Failure Centre, The Alfred Hospital, Melbourne, Victoria

RENAL IMPAIRMENT AND DIABETES MELLITUS AS PREDICTORS OF READMISSION IN PATIENTS WITH CONGESTIVE HEART FAILURE G.H. Tofler, I. Black, E. Barin. M. Staff. S. Hales, H. Tsakonis. Iparks. L. Mercer. L Hoooer, A. Binasis. S. Masoero. B.Morton. for the MACARF Study. Royal North Shore Hospital, St Leonards, NSW.

Background: Re-synchronisation of cardiac contraction with bi-ventricular pacing (BVP) has recently emerged as a useful adjunctive therapy for patients (pts) with heart failure (HF), although it is associated with considerable cost. At our institution, patients are only considered after aggressively managed anti-failure therapy for at least 6 months (particularly ACE inhibitors and beta blockers), nurse education and HF specific exercise rehabilitation. Suitable patients for BVP were: age ~70 years, NYHA Class 3 HF despite optimal drug therapy, left bundle branch block (LBBB) with QRS > 0.14 set, LVEF ~40 “A, VO2 max 14.20mls/kg/min, or ~50% predicted. Results: 10 patients underwent BVP insertion. 7 pts. GuidantB system, 3 pts Medtronic, (8M, 2F, mean age 62 years, f 9 0). Mean BVP procedure time was 2.9 hrs t 0.68. Lead placement was successful in all cases. No procedural complications occurred. All patients were discharged the following day. At 6 month follow-up, 1 pt. had died suddenly 2 months post procedure, 1 pt on immunosuppression developed pocket infection 5 months post implant and the BVP was removed. 1 pt had coronary sinus lead dislodgement 5 weeks post BVP with unsuccessful reinsertion. NYHA class improved significantly with no pt. experiencing worsening symptoms.

LVEF (%) NYHA Class

Baseline Mean * SD 27.67 + 8.4 2.76 f 0.4

6 mths follow-up Mean f SD 33.2 + 10.8 2.0 t 0.76

p lkO.18 NS P=O.O48

Conclusion: B&ventricular pacing, in carefully selected patients, can be done with few complications and a high rate of success. Significant improvement in NYHA Class and a trend to improvement in ejection fraction suggest this is a financially valid and useful treatment option for patients with severe HE

EFFECTS OF PERINDOPRIL ON CARDIOMYOPATHY IN BZ-ADRENERGIC RECEPTOR OVEREXPRESSING MICE: IMPORTANCE OF GENDER M.Krawczvszvn* , X Gao. A. Dart, X Du. Baker Medical Research Institute Melbourne , Australia. Cardiac specific over-expression of B2-adrenergic receptors (BZAR) by 200-fold in mice results in fibrotic cardiomyopathy, ventricular remodeling, heart failure and premature death. This mouse model is suitable for stidying the mechanisms of action and efficacy of current therapeutic drugs. We postulated that perindopril, an Angiotensin Converting Enzyme (ACE) inhibitor, would be beneficial in the j32AR over-expressing mice. METHODS: 46 B2AR transgenic mice were studied for a 9-month period, starting at 6 months of age. 20 j32AR mice (12 male 8 female) received perindopril in the drinking water, at a dose of 0.3- O.lmg/kg/day and another 26 animals (13 each of male and female) served as controls. Animals were inspected daily and their water intake was recorded weekly. Echocardiography was performed before treatment (bmth) and at 9,12 and 15 months of age. Dead animals had a post mortem examination to determine cause of death, tibia1 length and weight of vital organs. Hearts were removed for histological examination. RESULTS: All groups showed progressive reduction in left ventricular systolic function, as measured by fractional shortening (FS), but at 12 months the FS was better preserved in untreated females vs. males ( 28t3 % vs 16 * 2 % p< 0.05 ). The benefit of perindopril was found to be highly gender-dependent. Male animals did not have a survival benefit, and echo studies showed no improvement compared with control males. Treated females had a significantly higher survival rate and a reduced heart weight at the end of the study. (table), although there was no significant improvement in FS(30.4 + 2.1% vs. 27.6~ 3.1%). l2mth survival 15mth survival Heart weight mg Body weight 8

M treated 41.7% 9.1% 236 + 20 38* 2

M control

F treated

F control

53.8% 23.0% 250r 19 40* 3

87.5% 87.5%’ 142 + 11’ 35* 2

76.9%

18% 188 + 12 31+3

* (p < 0.05) CONCLUSIONS: Over-expression of BZAR at a very high level leads to a cardiomyopathy with a high mortality. Our data indicate that the severity of this phenotype is gender dependent. Similarly, the beneficial effect of an ACE inhibitor is only observed in females,

A75

,

Congestive heart failure (CHF) is an increasingly important cause of morbidity and mortality Comorbidities such as renal dysfunction and diabetes mellitus are common in patients with CHF, and complicate management. The purpose of this study was to determine predictors of CHF readmission in patients previously admitted with CHF. Methods: We prospectively studied 235 patients (mean age 77 years, 57% male). Serum creatinine >1.3mmol/L was present in 43%, and known diabetes mellitus (DM) was present in 25% of patients. We examined demographic and biochemical characteristics among the 29 patients who were readmitted at least once with CHF. Log rank testing was used for continuous values divided into quartiles. Results: Imuaired renal function-observed (medicted) screat SUrea

Ql

Q2

Q3

44

6(7.0) 7(7.6)

5(10.5) 3 (10.3)

ll(10.36)

7(1.1)

5 (6.7)

14 (4.5)

-value


DM was also associated with an increased risk for CHF readmission; events observed (expected) for DM(+) 14 (6.8); for DM(-) 15(22.6) p
LOCALISATION OF INCREASED CENTRAL MONOAMINE TURNOVER IN HUMAN HEART FAILURE TO THE SUBCORTEX urwal’. M. Esler, 1. Hastines. L. Iohnstone. and D. M.Kave. Neurocardiology Laboratory, Alfred Baker Medical Unit, Prahran, Vie. Background. Sympathetic nervous system (SNS) overactivity plays an important role in disease progression in heart failure. Increased central monoamine release, reflecting increased brain catecholamine turnover, occurs in heart failure (CHF). However, the location of the afferent receptors, and the pathways in the central nervous system (CNS) involved in eliciting heightened sympathetic activity, remain to be elucidated. Methods. 10 heart failure patients with elevated filling pressures, and 8 healthy volunteers were studied. Cerebral venous blood pool scans were performed for lateralisation of cerebral venous drainage (subcortex vs cortex). Bilateral internal jugular vein (IJV) cannulation was achieved, via the antecubital approach, and blood was sampled for venous overflow of norepinephrine (NE), and its major lipophilic intraneuronal metabolite, 3-methoxy-4-hydroxyphenylglycol (MHPG). Sodium nitroprusside (SNP) was administered intravenously to achieve a drop in both systemic and cardiac filling pressures, and bilateral IJV blood sampling was again undertaken Results. There was a trend for subcortical MHl’G release to correlate with total body NE release (p=O.O6). MHl’G release from the subcortex was significantly greater than from the cortex in CHF (p=O.O3). After the adminstration of SNl’, total body NE release was increased but subcortical MHPG release was decreased in CHF (p=O.O4). Conclusions. Brain sympathetic overactivity in CHF arises from the subcortex. Further, by reducing filling pressures with SNP, subcortical MHPG release in CHF was reduced. This suggests the existence of a reflex link, consisting of afferent neural traffic from the cardiopulmonary receptors and sympathetic efferent outflow from the brain.

A76

49th Annual

EFFICACY, CARVEDILOL P.S,.

Scientific

Meeting

of CSANZ

Heart,

TOLERABILITY AND LONG TERM EFFECTS . . A.M. w IN WOMEN m F Kotyk. St. Vincent’s Hospital, Sydney, Australia.

OF

Background: Women do not always exhibit the same physiological responses to heart failure therapy as do men. We wished to determine whether there are differences in tolerance of or response to carvedilol between males and females. Methods: Thirty-two women with NYHA Class I-IV heart failure have been commenced on open label carvedilol and followed up for 12 months. A comparative group of men receiving carvedilol was found by matching age, diagnosis, NYHA class and race. A suitable match was found for 25 women and a retrospective comparative study was conducted on this group. Results: Women (n=25) Baseline 3 months 12 months LVEDD 65kQ 63k6 6Oill LVESD 55*10 51*10 46f12 FS (%) 0.15*0.05 0.2’&0.07* 0.21iO.06’ 0.26*0.10 EF (%) 0.36tO.09’ 0.36iO.09’ Men (n=25) LVEDD LVESD FS (%) EF (%)

Baseline 3 72kQ 63kQ 0.12f0.04 0.24f0.06 ’ ~~0.05 compared

months 73*9 61flO 0.16kO.06” 0.30f0.07’ to baseline

12 months 69fQ 57ill 0.21iO.15’ 0.32*0.09’

Twenty-four percent of females withdrew due to intolerable side effects (nausea, headaches, lethargy, hypotension, worsening heart failure) compared to 6% in the male group (fatigue, myalgia). Conc/usion: Although women taking carvedilol suffer significantly more side effects than men, improvement in fractional shortening and ejection fraction were comparable for both sexes. Therefore, if the side effects can be tolerated it is beneficial for women to remain on carvedilol. PREDICTION L.M. Davis*

AND MECHANISMS OF RESPONSE TO CARVEDILOL Cardiology Unit, Westmead Hospital, Sydney, N.S.W.

B-Blocker (BB)s are beneficial in patients with systolic heart failure. To elucidate some of the mechanisms of response to Carvedilol we evaluated 10 patients with clinical review, serial gated heart blood pool scan (GHBPS)s and echocardiography during the first 6 months of drug therapy. All patients were on an ACE inhibitor and had NYHA type 2 to 3 heart failure (HF). Dilated cardiomyopathy was present in 7 patients, ischaemic heart disease (IHD) in one and aortic valve disease in 1 patient. Four patients used other (BB)s prior to Carvedilol. Examined outcome variables included:type of H.F., previous B-Blocker (B.B) use, cardiac pathology; and various echo measurements. l&,&s: Some clinical, echocardiographic and GHBPS parameters improved in all but 1 patient following the introduction of carvedilol. Favourable remodelling (reduction in LV dimensions, improved doppler indices of diastolic function, and an increase in LVEF) occurred in 5 patients..Improvement in systolic function but not diastolic function occurred in 2 patients. Improvement in doppler estimates of diastolic function only occurred in 2 patients. One patient deteriorated in both estimates of systolic and diastolic function.

Outcome N Favourable Mixed Response !3eterioration

Systolic HF

Mixed HF

5 3 1 1

4 2 2

Diastolic HF 1 1 0

B.B 4 2 1 1

No. B-Blocker 6 4 2 0

Non responders had dilated cardiomyopathy in 3 cases and underlying IHD with chronic renal failure in 1 patient Conclusions: Carvedilol improves some echocardiographic measures of both systolic and diastolic determinants of heart function in most patients. Prediction of response is not possible based on simple clinical and echocardiographic parameters

Lung

and Circulation

2001; 10

ACE GENE POLYMORPHISM CHRONlC HEART FAILURE

IS NOT A PREDICTOR OF OR AEROBIC FITNESS. MJ. Andason*, MkFebbraio.S.B.Hana~.A.WilliamsMJ.CarW,S. Se.lieaodD.L.Hare. Physiology [email protected], [email protected] of Melbounie, parkville, Dqrbnent of [email protected],Heide~ Centrefor Rehabilitation, Em&e atxl Spt Science, Victoris Univ&ty, Footsaay. Angieverting enzyme (ACE) [email protected]@zlelion basbmlinMtoslsoeptibilitytochronicbealt~lne(cHF)dtoatbl~c

(IQ

[email protected]

paformance.

M&c&Tofu&erexamine tkx hqpotheses 29 (CHF) patients (63Uyezux; LVEF 27i7%), 69 elite endurance alhletes (27iloyearS; 5% world bed rjmes), sncl26 sdaday coomh (24+va1s, 0 aaobic cctiviti-) -.wx xzruikd Venous blood samples wee o&ned

6nm each subject for DNA

exhaction

ACEJ/[email protected] chainleadim(PcR)nlethodAerobicfitnesswas~bymeaslningtolsl body oxygen nptdce (VQ nimii’kg’) on a cycle ergome&. ACE I/D po~(andIversusDallelefirequencies))CCHFpatigds~)~elite athleteswereaqa.IEdwitht&eofs&d&aIycontrols.7he~p betweenACEVop~IDandDD)andV~~assessedfor exhoftksethKqluq6kngalUl~ofvariance. Res&TheACEgencQpekqoenciesforallthreegmupswereinHatdyWeinb~equiliki~‘ThzwasnoditkxxinACEL’Dpolymoqhisn (P4.68) or allele tiquenq (w.45) klween CHF @s md conlmls. Siiy, there was IY) r5tEmce in ACE I/D polymo~ (P=O23) and allele litqenq(FQ.68)~atllletesandcontmkIncHF~v~wasnot signilicantlyrelatedtoACEpolymaphisn,although~wasakndto~ a @ient of V% (II lw.5, ID 15.8G.7, DD 14&3.8; P=QO8). In seda&rycontmlsthuewasno&tiot&ipbetvxenV~~ACE [email protected](lI33.4+lS,ID 33.2~05, DD32&1.8;P=O.94). Con~These~donotsuppoaarolefartheACEgeneinthe dzzvelopment of CHF nor io predicting aerobic fi!ness. Ho-, the relatiomhip of ACE gene [email protected] to V(& in CHF pts rqti fin&z inv&igation CHANGE IN VASCULAR OCCLUSION. SA Centre, Monash University,

PERMEABILITY Monash

Medical

FOLLOWING CUFF ARTERIAL Cardiovascular Research Centre, Melbourne.

The endothelium plays a central role in controlling many vascular functions including vascular tone, thrombosis and permeability. Impairment of endothelial control of vascular tone in response to changes in blood flow may be demonstrated in patients with coronary artery disease by ultrasound following temporary cuff occlusion of the brachial artery. Nitric oxide is

known

to play an important

role in this process,

and also influences

vascular

permeability. We therefore sought to examine the changes in plasma colloid osmotic pressure (PCOP), a potential index of vascular permeability, in healthy volunteers and patients with coronary artery disease following cuff arterial occlusion of the brachial artery. Venous blood was obtained from a vein at the antecubital fossa of 71 healthy volunteers (34 male: 37 female, age 22.44 f 12.16 years, mean + SD) without overt vascular disease and 10 patients with known coronary artery disease (8 male: 2 female, age 59.40 + 10.65 years), after 20 minutes lying supine and 3 minutes after release of a cuff applied to the forearm and inflated to 30mmHg above systolic blood pressure for 5 minutes. Plasma samples were analysed with an Osmomat 050 Colloid Osmometer with a 1OKDa molecular weight cut-off membrane and 0.9% saline as the reference solution.

There was no difference

between

the 2 groups

in the resting

PCOP (26.2 k

1.93mmHg). There was a fall in PCOP following release of cuff arterial occlusion in most subjects. The distribution of the fall was not normal in either group. The median fall in PCOP in healthy volunteers was 0.94mmHg, which differed significantly from that in patients with coronary artery disease O.lSmmHg (p
Heart,

Lung

and Circulation

49th Annual

2001; 10

DOBUTAMINE IMPROVES CARDIC WORK EFFICIENCY IN HEART FAILURE (HF) Y Huane’, K Shirota, T Yuasa, T Ramanathan and Hunvor S.

Cardiac Technology Centre, Department of Cardiology, Hospital, St Leonards (Sydney), NSW 2065, Australia

Royal

North

Shore

Energy inefficiency is characteristic of HF and manifests as decreased work efficiency (ratio of external work: EW to LV pressure volume area: PVA). Previous studies demonstrated that dobutamine enhanced myocardial oxygen consumption for basal metabolism [l]. We studied the effect of dobutamine on energy transfer from PVA to EW in 13 sheep (49 + 5 Kg) following chronic HF induction by staged coronary micro-embolisation. HF constituted 4 weeks stable LVEF reduction by 50% from baseline. The LV pressure volume relationship (LV I’-VR) was studied with conductance and pressure transducer catheters under general anaesthesia. Ratio of arterial elastance (Ea) to LV end systolic &stance (Ees) describes ventriculoarterial coupling. LV P-VR was recorded before (HF B) and after (HF D) dobutamine infusion to a heart rate of 140. Dobutamine increased LV work efficiency by 43% in HF resulting from significant increase of EW without change of PVA. It also increased LV contractility (Ees) with resulting improvement in ventriculoarterial coupling (Table). It is concluded that dobutamine increases LV work efficiency in uncomplicated, moderate, chronic ischemic HF by improving ventriculoarterial coupling and increasing external work. HF B (1~13) HFD

EWiPVA 0.4 f 0.11 0.57 * 0.15 *

EW 2138 + 707 2790 + 696 *

PVA 5321 TL1198 5274 + 925

P< 0.05 compared between HF B and HF D (paired 111 Suga H. Am. J. Dhysiol. 1990; 70: 249-277.

VENTRICULOARTERIAL EFFICIENCY IN SIX

UNCOUPLING MONTH DIABETIC

K.Shirota. T.Nishimura. X.Zhene. Centre, Department of Cardiology, NSW.

EdEes 2.5 * 0.9 1.6 * 0.7 *

student

EM

1.1 + 0.3 2.2 f 0.6 *

t-test)

AND IMPAIRED WORK SHEEP. T.Ramanathan’,

Y.Huaw SHunvor. Cardiac Technology Royal North Shore Hospital, St Leonards,

Diabetic patients have an increased mortality secondary to ventricular failure following AMI and CABG. The specific mechanisms that contribute to this adverse prognosis are controversial. To investigate the mechanisms underlying ventricular dysfunction we evaluated the impact of diabetes on ventriculoarterial coupling and left ventricular (LV) work efficiency. Type I diabetes was induced in six sheep with streptozotocin. At baseline and 6 months after diabetes was established the LV pressure-volume relationship was determined using the conductance catheter technique. The slope of the LV end-systolic pressure-volume relationship (Ees), effective arterial elastance (Ea = LV end-systolic pressure / stroke volume), external work (EW) and pressure-volume area (PVA) were measured. Ventriculoarterial coupling (Ea/Ees) and LV work efficiency (EW/PVA) were derived. At baseline the LV and arterial system were optimally matched (Ea/Ees 1.1 + 0.2). After 6 months diabetes Ees decreased 25.1% f 14.9% (~~0.02) while Ea and EW did not change significantly, with resulting ventriculoarterial uncoupling (Ea/Ees 1.9 + 0.5, p
Scientific

Meeting

of CSANZ

A77

SYMPATHETIC AND PARASYMPATHETIC FUNCTION IN LUNG TRANSPLANTATION PATIENTS AT REST AND FOLLOWING AUTONOMIC PERTURBATION A.Berakisl*. T. Willams2. M. Naughton2,

J, Martin’, M.Muhlma&. H.Krum~~ Clinical Pharmacology Unit’ and Department of Respiratory Alfred Hospital Melbourne, Prahran, Victoria 3181.

Medicine*,

Lung transplantation patients have been observed to have an elevation in resting heart rate (HR) which may have adverse prognostic significance. However, little prior assessment has been made of factors which may be contributing to this. The aim of the present study was to investigate whether autonomic dysfunction exists in the setting of lung transplantation. To do so, we compared parasympathetic (I’NSA) and sympathetic nervous system activity (SNSA) in 22 lung transplantation patients (50.5 r 2.4~) and 13 normal subjects (48.2 + 3.7~) by performing heart rate variability (HRV) measures of PNSA and plasma noradrenaline (NA) at baseline and during an 8000 head up tilt, as well as assessing blood pressure (BP) and HR responses to Valsalva manoeuvre and cold pressor test. Lung transplant patients (LTx Pts) had decreased baseline time and frequency domain HRV variables compared to normal subjects (rMSSD: 11.21 f 1.1 VS 30.33 f; 4.50ms, Ln high power (HP): 2.41 + 0.20 vs 4.8 r 0.40 ms2, LnHP: total power ratio: 2.74 * 0.18 vs 3.39 f 0.20 %; all P < 0.05). Furthermore, only LTx Pts were unable to decreased these parameters further with tilt unlike normal subjects. Ln low frequency power: LnHP ratio was altered in LTx Pts (1.56 f 0.25 vs 0.77 + 0.27 in normals: P < 0.05), indicating an increase in sympathovagal balance towards increased sympathetic predominance. Baseline plasma recumbent plasma NA was increased in LTx Pts compared to normal subjects (3.25 + 0.43 vs 2.00 + 0.27 nmol/L; P < 0.05), with both groups significantly increasing plasma NA with tilt. There were no differences between the two groups in HR or mean systolic BP responses to the Valsalva manoeuvre and cold pressor testing. Thus, increased resting HR in lung transplantation patients appears to be due to both reduced PNSA and increased SNSA. Furthermore, these patients appear to have preserved capacity to respond to autonomic perturbation by increasing SNSA, but not by further withdrawal of vagal tone.

CARDIAC GRAPHIC TRALIAN

TROPONIN I, EJECTION FRACTION AND ECHOCARDIOWALL MOTION IN ATHLETES COMPETING IN THE AUSIRONMAN TRIATHLON A. La Gerche. A.I. Bovle*. A.M. Wilson

and D.L. Prior. Cardiac Vie.

Investigation

Unit, St Vincent’s

Hospital,

Melbourne,

Controversy exists as to whether prolonged exercise has a detrimental impact on the human heart. Elevated specific cardiac enzymes and regional wall motion abnormalities on echocardiography have been detected within thirty minutes of completion of the Hawaii Ironman Triathlon event. It is not known whether such abnormalities represent transient or prolonged changes, Fifteen male athletes were studied in the week prior and five days following completion of the Australian Ironman Triathlon - 3.8 km swim, 180 km bicycle ride and 42.2 km run. Electrocardiogram (ECG), creatine kinase (CK), CK MB isoform (CKMB), cardiac troponin I (cTnI), and echocardiography were assessed in all subjects. Left ventricular ejection fraction (LVEF) was measured by Simpson’s rule and sixteen segment wall motion analysis was performed. All subjects completed the triathlon: ECG’s were unchanged in pre and post race comparisons. CK (U/L) CK-MB NJ/L) CK-MB (%) cTn1 > 0.3 giI LVEF (%)

Pre 195 11.9 6.0 0 65.8

Post 451 15.9 4.4 1 athlete 66.1

P value 0.01 0.03 0.02 N.S. N.S

Both CK and CKMB were significantly elevated post race, but the CKMB percentage decreased. Cardiac Tnl remained undetectable in all but one subject. Ejection fraction was unchanged. One subject demonstrated regional wall motion abnormalities in four of sixteen segments. On follow-up, at 28 days post race, echocardiography revealed resolution of these segmental changes, Although transient abnormalities of cardiac wall motion may be detected, ultra endurance exercise in trained athletes does not result in myocardial necrosis or detectable permanent cardiac impairment.

A7!3

49th Annual Scientific Meeting of CSANZ

Heart, Lung and Circulation 2001; 10

MECHANISMS INVOLVED IN ENHANCED MUSCLE GROWTH BY IGF-I AND CSL, A NOVEL MUSCLE-SPECIFIC PROTEIN. T.Yeoh’. SPalmer. N Groves. A.Schindeler. C Biben a d R.P Harvey. The Victor Chang Cardiac Research Institute: Darlingnhurst. f&W.

CARDIAC

Background: Skeletal muscle wasting is a significant complication of heart failure and is associated with inactivity and declining cardiovascular fitness. Understanding the molecular mechanisms of muscle growth may aid development of therapeutic options. Csl is a novel gene encoding a musclespecific protein. Over-expression of Cslin the myogenic cell line C2C12 results in mildly enlarged myotubes. Co-administration of the growth factor IGF-I exacerbates this phenotype resulting in grossly “hypertrophied” myotubes (myosacs). Recently, activation of the calcineurin (Cn) phosphatase / NFAT (transcription factor) pathway has been implicated in both cardiac and IGF-induced skeletal muscle hyperlrophy. The aim of this study was to examine the mechanisms involved in the Csl/lGF myosac phenotype and in particular, whether the Cn/NFAT pathway mediated this process. Methods: In the presence or absence of the Cn inhibitor cyclosporin A (CsA), myosac formation was examined for cell morphology, protein/DNA content and with assays involving components of the Cn/NFAT pathway. Results: We found that myosac formation did not involve anabolic metabolism, a component of skeletal muscle hypertrophy, as indicated by protein/DNA ratios. Furthermore, myosacs contained many more nuclei than controls. This suggests that myosacs develop largely by dysregulated cell fusion. Interestingly. myosac formation was also associated with increases in NFAT activity. In contrast, Cn activity was enhanced by IGF but not modulated by Csl. Furthermore, CsA, whilst abrogating Cn activity, did not inhibit the myosac phenotype and only minimally attenuated the stimulated NFAT activity. This indicates that myosac formation is independent of Cn, although it may be mediated by NFAT. Conclusion: These data demonstrate that enforced expression of Csl with IGF-I results in enlarged myotubes together with augmentation of NFAT activity which is Cnindependent Future experiments will examine whether the Cn-independent NFATS is sufficient to reproduce myosacs or if indeed, NFATs are regulated by alternative phosphatases. Csl-related pathways may provide a target for gene therapy to induce enhanced muscle growth.

Energy starvation is characteristic of heart failure (HF). Using the left ventricular pressure volume relationship (LV P-VR) we studied work efficiency and energy transfer from mechanical to external work in a sheep model of chronic HF induced by staged coronary micro-embolisation [l]. Thirteen sheep (49 f 5 Kg) were instrumented with conductance and pressure transducer catheters under general anaesthesia to record LV P-VR. The ratio of external work (EW) to LV P-V area (PVA) represents work efficiency, whereas the ratio of arterial elastance (Ea) to LV end systolic elastance (Ees) describes ventriculoarterial coupling. Studies were performed at baseline (B), HF establishment (HF), and 3 and 6 months (mo) later. LV failure induction resulted in 50% decrease in EF persisting over 6 months (Table). LV work efficiency and contractility (Ees) were both reduced (by 17 to 23% and 48 to 62%). Mismatch of ventriculoarterial coupling also occurred, mostly from decrease of LV elas-

GENDER INFLUENCES ASSESSMENT OF LEFT VENTRICULAR CHAMBER SIZE. R. French* T.L. Gentles Departments of Paediatric Cardiology and Cardiology, Green Lane Hospital, Auckland, New Zealand Background: Left ventricular (LV) chamber size is known with body surface area (BSA), but may also be influenced graphic and somatic features. Objectives: To investigate factors associated impact on identification of LV dilatation.

with

LV chamber

to be associated by other demo-

size and their

Methods: M-mode echocardiocardiograms were undertaken in 158 normal subjects (89 male, 68 female), median age 21.9 years, range 6 - 62 years; and in 247 patients with aortic and/ or mitral regurgitation, and/ or acute rheumatic fever (157 male, 90 female) median age 14.9 years, range 4 - 72 years. End diastolic dimension (EDD) was corrected for BSA and expressed as a z-score. (z-scores of -1 and 1 indicate an EDD 1 SD below and above the normal population mean at a given BSA). Results: There was a significant relationship between EDD z-score and gender in normals (mean z-score males 0.3, and in females 4.4, p < 0.001). There was no relationship between EDD z-score and weight, height, BSA or age. In the patient group, the mean EDD z-score gender was 4.0 in females corrected for BSA and gender vs. 3.2 when corrected for BSA alone (p < 0.001) In males the mean EDD z-score was 3.8 corrected for BSA and gender VS. 3.6 COP rected for BSA alone (p < 0.001). Uncorrected for gender, 1 male was incorrectly identified with LV dilatation, while 11 females were incorrectly categorised as having a normal ventricle. Conclusions: LV chamber size is related to gender as well as BSA. Failure to account for gender will result in incorrect identification of LV size especially in females.

WORK EFFICIENCY IN CHRONIC ISCHEMIC HEART FAILK Shirota. T Yuasa. T Ramanathan. and S Hunvor. Cardiac Centre, Department of Cardiology, Royal North Shore Hospital, (Sydney), NSW 2065, Australia.

URE Y Huane”. Technology St Leonards

B (1~11) HF (1~13) 3mo h=ll) 6x110 (1~11) EF 59+8 29*5 29+6 29 f 7 EW/l’VA 0.52 f 0.11 0.4 * 0.11 * 0.43 + 0.09 * 0.42 f 0.11 * EW 2599 ~585 21382707 1953+734 2156k744 Ea/Ees 1.3 f 0.5 (n=lO) 2.5 * 0.9 * 2.1 + 0.6’ 2.0 f 0.7 * Ees 2.9 f 1.4 1.1 * 0.3 ’ 1.4 i 0.5' 1.5 + 0.4 * +: lQO.05 compared with baseline (ANOVA followed by post hoc test). Even in the absence of arterial and other concomitant disease, our sheep ischemic HF model exhibits deranged ventriculoarterial coupling, resulting in inefficient energy transfer. This inefficient energy state is stable for 6 months. (11 Huane YF, et al. ASAIO J. 1997; 43: M408-413.

LEFT SIDED SUPERIOR Auckland, New Zealand

VENA

CAVA

A.L. Calder*

Green

Lane Hospital,

A left sided superior vena cava (LSVC) was found in 169/1600 heart specimens (10.6%). The LSVC connected to the coronary sinus to drain to right atrium in 121 (7.6%) and connected to the left atrium in 48 cases (3%). In situs solitus, a LSVC connecting to the coronary sinus was associated with tetralogy of Fallot in 35/121 (29%), with double outlet right ventricle in 9 (7%), ventricular septal defects in 9 (7%) or coarctation in 9 (7%) and a miscellaneous group in the remaining 50%. A bridging left innominate vein was found in only 16% (in 9/56 cases where this could be assessed). The right sided SVC was absent or atretic in 3 cases with tetralogy. Anomalous pulmonary venous connection occurred in 6 cases (total in 2 and partial in 4). The coronary sinus was partially deroofed in 2 cases. The orifice of the coronary sinus to right atrium was atretic in 4 cases and opened into left atrium as well as right in 2 others. A LSVC connecting to left atrium was associated with heterotaxy syndromes in 33/48 (69%), common atrioventricular canal defects in 4 (So/,), and a variety of complex lesions in 11 (23%). A bridging innominate vein was found in 29% (in 7/24 cases where this could be assessed). The coronary sinus was absent in 36 cases (75%) with the coronary veins draining to the adjacent atrium. The coronary sinus was partially deroofed in 5 (10%) and the orifice atretic in a further 2 (4%). The right sided SVC was absent in 8/48 cases (17%). Awareness of the variety of anomalies of the superior systemic veins may aid in diagnosis and help in planning therapeutic procedures, e.g., partial or total cave-pulmonary anastomoses or insertion of transvenous pacemakers.

Heart,

Lung

and

Circulation

2001;

10

49th

Annual

Scientific

Meeting

of CSANZ

A79

SURGERY FOR RHEUMATIC MITRAL VALVE DISEASE IN CHILDREN AND ADOLESCENTS. C. K. Choone*, C. O’Donnell. T. West. T. L. Gentles, A. Departments of Paediatric Cardiothoracic Surgery and Paediatric Cardiology, Green Lane Hospital, Auckland, New Zealand.

SINGLE CENTRE INTERMEDIATE-TERM OUTCOME OF TRANSCATHETER SECUNDUM ATRIAL SEPTAL DEFECT CLOSURE USING THE CARDIOSEALrM SEPTAL OCCLUSION DEVICE. GKLane’, Rhodes, CI Mesia. IA Beers, AH Toth and LA Latson. The Cleveland Clinic Foundation, Cleveland, Ohio, USA.

Green Lane Hospital provides a paediatric surgical service for New Zealand and the South Pacific region. The patient population is unique in that late presentation is common and postoperative anticoagulation monitoring may not be possible. Because of this, mitral valve repair is frequently performed on severely affected valves. Between 1990 and 1999, 73 patients (41 males) aged 13.5+4.0 (3.7-20.5) years underwent rheumatic mitral valve surgery. Neighbouring Pacific Islanders made up 53% of patients, NZ indigenous Maori 30%, NZ Polynesians 15% and Caucasians 1%. Mitral regurgitation was present in 81%, stenosis 5% and mixed disease 14%. There was concomitant aortic or tricuspid disease in 73%. 45% had active carditis. Preoperatively 8 patients required preoperative ICU support and 74% were in NYHA class III or IV. Repair was undertaken in 42% and replacement in 58%. 49% also had aortic or tricuspid surgery. The m-hospital mortality was 4%. No deaths occurred in the acute carditis group or the 8 patients who required preoperative ICU care. Patients with acute rheumatic fever were no more likely to require mitral valve replacement than those without active carditis (17/33 vs 26/40, p=NS). Follow-up was 86% complete, mean duration 24(0.9-76.6) months. There were 3(4%) reoperations (mean interval 36 months) and I late death. At follow-up, 48 patients were in NYHA class I and 11 patients in class II. Despite significant preoperative morbidity and severely affected valves, rheumatic mitral valve surgery in children and adolescents can be associated with low operative mortality and good clinical outcome. Acute rheumatic carditis is not associated with an increased need for mitral valve replacement.

septal occlusion device has been used in Background: The CardioSeaP clinical trials since 7/96 for secundum atria1 septal defect (ASD) closure. Methods: Cleveland Clinic data from patients enrolled in the prospective trial of the CardioSeaP device were analysed for incidence of residual leak, the need for further intervention and major complications. Chest X-ray, transthoracic echocardiography (ITE) and electrocardiography were performed at 1, 6, 12 and 24 months post deployment. Results: Sixteen patients (14F/2M), median age 18 years (5+66) with a Qp/Qs of 1.8 * 0.3 and ASD size of 10 mm r 2.5, had deployment of 23-+33mm CardioSeaP devices. Fluoroscopic balloon stretched ASD diameter was 13.5mm + 2.5 with device/stretched diameter ratio of 2.1 f 0.3. Immediate TEE demonstrated no leak in l/16, trivial/small leak in 11/16 and moderate leak in 4/16 of patients. All patients have been clinically reviewed 12 months or more post implantation, with a median follow-up of 2 years (0.99-2.95). TTE demonstrated a persisting leak more than trivial/small in 3/16 at 1 month, l/15 at 6 months, l/13 at 12 months and l/l1 at 24 months. The right ventricular end-diastolic dimension decreased by a median of 18.5% by 1 year. Device arm fracture/s were found in 3 patients by 6 months post implantation with 1 additional later fracture. There have been no clinical complications. Conclusions: The CardioSealrb’ device can be implanted safely in haemodynamically significant ASDs with a subsequent reduction in the size of the right ventricle. The presence of arm fractures was not associated with functional failure of the device. There is a trend for residual leaks to decrease over the first 6 months and only 1 patient has a leak large enough to consider further intervention in the medium term.

DOES THE RIGHT VENTRICULAR OUTFLOW TRACT MYOCARDIUM OF HEARTS WITH TETRALOGY OF FALLOT HAVE A DIFFERENT b ADRENERGIC SIGNALLING RESPONSE? wlalali”. P.G. Pohlner. The Queensland Centre for Congenital Heart Disease, The Prince Charles Hospital, Brisbane, Australia. OBJECTIVE: Right ventricular outflow tract (RVOT) obstruction is a dominant feature of Tetralogy of Fallot. Acute RVOT contraction may exacerbate the anatomical obstruction and can lead to life threatening hypoxic spells. We studied dynamics of either B,- or Bz- adrenergic receptor stimulation in strips of RVOT myocardium in Tetralogy of Fallot and also compared them to RVOT myocardium of non-cyanotic congenital heart disease. METHODS: RVOT myocardium from 6 children (age range 23 days - 11 years, average 30 months) with a ventricular septal defect (VSD) and 16 children (age range 1235 months, average 18.4 months) with Tetralogy of Fallot was paced in vitro at 60 beats per minute. Stimulation of B,- adrenergic receptors was obtained with (-) -norepinephrine in the presence of a Br- blocker (ICI 118,551) and fir- receptors with (-) epinephrine in the presence of a B,blocker (CGP 20712A). Effects obtained in VSD were compared to results in Fallot. RESULTS: Stimulation of B,- adrenergic receptors with (-) -norepinephrine and Bz- adrenergic receptors with (-) -epinephrine caused concentration dependent increases in contractile force and shortening of the relaxation time in RVOT myocardium from infants with VSD. The potencies (-log concentration causing 50% effect) of (-) -norepinephrine for increasing contractile force (VSD 5.8 +0.3, n = 6; Fallot 5.5 + 0.1, n = 16, p = 0.2) and shortening the time to reach 50% relaxation (VSD 6.2 +O.Z; Fallot 5.7 * 0.2, p = 0.2) were not significantly different as was the case for (-) -epinephrine for force (VSD 5.6 + 0.2, n = 7; Fallot 5.6 + 0.1, n = 21, p = 21) and time to reach 50% relaxation (VSD 6.1 i 0.3; Fallot 5.8 + 0.1, p = 0.4). CONCLUSIONS: Activation of Br- and Bz- adrenergic receptors has similar positive inotropic and lusitropic effects in RVOT myocardium from infants with Tetralogy of Fallot and VSD. Non-selective B- blockers may be more effective than selective (Br) blockers.

ECHOCARDIOGRAPHY PRIOR TO TRANSCATHETER CLOSURE ATRIAL SEPTAL DEFECTS. P.G.Biernstad’. H. tional Centre. Rikshospitalet, The National Hospital, Oslo, Norway

OF

Closure of atria1 septal defects with the Amplatzer device has become a standard therapy in many centres. The judgement prior to catheterisation whether or not the defect is suitable for such treatment is made by echo. In our series of 56 implantations, initially the echo studies were all performed by the interventionist, later this applied only for the children. The errors were one anomalous pulmonary vein overlooked, and one azygos continuation not discovered. After the first 30 implantations adult cardiologists from all over the country referred patients to us with a videotaped echo examination. These were either with transthoracic or transoesophageal approach and often considered to be of “good” or “good enough” quality. Seven patients with less good echo were reechoed in our hospital. Four of them were accepted for closure. Twentytwo patients had been accepted for closure, but four excluded at admission after repeat transthoracic echo. The remaining 18 patients were catheterised. Three of them had too big defects to be closed, a fourth insufficient caudal rim, in one the anomalous septum did not support the device and in another the device embolised. Thus 6/18 of the procedures were unsuccessful if the initial echo examination had taken place in an institution not involved in transcatheter closure. Such institutions tend to focus too much on the defect itself and pay too little attention to the walls surrounding it. We conclude that echocardiographic examination prior to transcatheter closure should be performed in the very institution that also carries out the closure procedures.

[email protected]

49th Annual Scientific Meeting of CSANZ

Heart, Lung and Circulation

TISSUE DOPPLER IMAGING IN HEALTH AND DISEASE; FINDINGS IN YOUNG AND OLD CONTROLS, PULMONARY HYPERTENSION AND DILATED CARDIOMYOPATHY. D. Mou”. U. Premawardhana, D.S. Celermajer. Department of Cardiology, Royal Prince Alfred Hospital, Sydney Tissue Doppler Imaging (TDI) is a novel modality assessment of myocardial velocity throughout echocardiography. This technique might provide cardiac physiology in healthy and diseased hearts.

allowing the quantitative the cardiac cycle, during useful information about

We therefore performed detailed TDI interrogation of the left and right ventricular free walls (LV,RV), at the level of annulus, base and mid-chamber, using a standardised protocol, in 70 subjects: 20 healthy young controls (30+5 years) (tests repeated on a different day in 10 of these); 10 older controls, free of known heart disease (65+6 years); 20 age-matched older subjects with pulmonary hypertension (PHT) (RV/RA gradient 48+8mmHg); and 20 agematched older subjects with dilated cardiomyopathy (DCM) (LV diastolic dimension 72+8 mm, shortening fraction 14k6 %). In each location, systolic (sys) and diastolic velocities (early, Em and atrial, Am) were measured by TDI. In the young adults, the results for systolic and diastolic parameters were generally reproducible (interobserver r-values up to 0.98, mostly -0.80-0.85). Both systolic and diastolic velocities showed significant annulus to apex gradients for both LV and RV. In the LV, systolic velocities were highest at the annulus (annulus: 7.11+1.66m/s, base: 6.69+2.70m/s, mid-chamber: 4.90&3.05m/s; p< 0.05), whereas in the RV, the fastest velocities were recorded from the basal regions (base: 10.99+1.56m/s, annulus: 9.72+1.34m/s, midchamber: 8.05&2.56m/s; p< 0.05). Compared to young controls, “old” controls showed reduced early diastolic and increased atria1 diastolic velocities in both LV and RV (LV annulus Em velocity -12.66+3.03m/s in young, 4.29+2.18m/s in old; Am velocity -3.80+1.44m/s in young, -8.64*2.75m/s in old, p< 0.01 for both comparisons), however systolic velocities were similar between these groups. In the PHT group, RV relaxation was impaired at the annulus (p= 0.006), but all other parameters were similar to controls. In those with DCM, LV and RV systolic and diastolic velocities were significantly slower than in controls (e.g. LV annulus systolic velocity 2.79*1.67m/s in DCM group, 6.51+2.47m/s in controls; p< 0.01). Therefore, TDI allows the reproducible measurement of LV and RV myocardial velocities in systole and diastole, and may provide novel insights into age- and disease-related changes in myocardial function in humans.

WHAT ARE THE DELAYS IN PRIMARY INFARCT ANGIOPLASTY WHEN PERFORMED AFTER HOURS AND DO THEY INFLUENCE OUTCOMES? Y Kovama’. PS Hansen, HH Rasmussen and GIC Nelson Royal North Shore Hospital, St. Leonards. Primary infarct angioplasty (PA) is a superior reperfusion strategy to fibrinolytic therapy (FT) when performed within working hours. ET however is the preferred strategy in most hospitals out of hours in part because of concern that time delays of PA will adversely affect patient outcomes. We performed a prospective comparison of the hospital outcomes (death, stroke and re-infarction) in 352 consecutive patients (age 31-94 yrs) presenting with acute myocardial infarction (AMI). From June 1997 until September 2000 150 patients presented between 7am and 6pm (in hours: IH) and 202 presented between 6.59am and 6.01pm Monday-Friday and on weekends and public holidays (after hours: AH). No FT was used in this period. Only patients transferred from other hospitals were excluded. At angiography 9.4% were Killip 3-4, TIMI O-2 flow was in 73% and 25% had ejection fraction less than 40%. TIMI 3 flow was established in 96% within 64 mins from diagnosis. Table shows median time delays (mins) Pain onset to 1st ECG 1st ECG to team notification Team notification to TIM1 3 flow Pain onset to TIMI 3 flow

IH

AH

110 19 58 206

110 28 74 240

P ,003 ,001 ,026

In hospital death was 3.5% (IH) and 2.9% (AH), re-infarction was 1.3% (IH) and 2.0% (AH) and stroke was 3.5% (IH) and 1.5% (AH) predominantly in elderly patients after emergency cardiac surgery. We confirm that the majority of infarct patients present out of hours and conclude that the 34 mins additional time delay in achieving reperfusion after hours does not adversely influence patient outcome. Hospitals with facilities for PA should consider routine use of the treatment after hours.

2001; 10

DOBUTAMINE STRESS ECHO REVEALS IMPAIRED CARDIAC FUNCTION IN ADULT SHEEP EXPOSED TO DEXAMETHASONE EARLY IN GESTATION. J Morranlf, M Dodicz. K Moritzz. M Wintour-Coehlanz, J&&g1 and 1 Wongl. ‘Department of Cardiology, Royal Melbourne Hospital,Victoria, ’ Howard Florey Institute, University of Melbourne, l’arkville, Victoria. BACKGROUND: We have shown that exposure of pregnant ewes to dexamethasone (11.5 mg/day for 2 days) at 27 days of gestation (term 150 days) results in offspring with increased blood pressure(BP) and cardiac output (CO) (Group D). AIM : To assess whether dexamethasone induced hypertension was associated with left ventricular hypertrophy (LVH) and reduced cardiac functional reserve(CFR) (CO,a,-CO,,,,,,). METHODS: 6 control animals (group C) and 5 group D animals were instrumented with Swan-Ganz catheters and volume loaded with Haemaccel until a constant CO was maintained with further volume loading (baseline wedge pressure). This wedge pressure was maintained during incremental doses of dobutamine (l-12pg/kg/ min), while BP and CO were measured. The same protocol was repeated in each animal 5 days later under mild general anaesthesia (1.5% Isoflurane) while transthoracic echocardiographic meaurements were obtained. RESULTS: Mean arterial pressure (measured for 3 days continuously) was significantly higher in Group D vs Group C (90+1 vs 80+1 mmHg;p
C (~6) 120~5 269k9 149klO

D (n=5) 143elO’ 232~20 89+10#

CONCLUSION: Brief prenatal exposure opment of hypertension,left ventricular functional reserve in adult life.

Anaesthetised C (~6) 108*12 263518 155*23 54*14

to dexamethasone hypertrophy and

D (n=5) 117*9 209r18 92+17’ 21+10*

led to the develreduced cardiac

FUNCTION IN RIGHT VENTRICULAR DIASTOLIC IRREVERSIBLE CHRONIC REVERSIBLE AND OBSTRUCTIVE AIRWAYS DISEASE R Shameem*. N Martens. S Holt. T O’Meeehan, Dept. of Cardiology, Wellington Hospital, Wellington, New Zealand. Right ventricular diastolic function can be adversely affected in patients with chronic obstructive airways disease (CORD), particularly in those with evidence of pulmonary hypertension, This study assessed right ventricular diastolic function using Doppler echocardiography in patients with reversible (asthma) and irreversible (emphysema) CORD. Correlation was obtained with pulmonary artery acceleration time. Right ventricular (RV) diastolic function was assessed in 40 patients. 10 had asthma, IO had emphysema and 20 were age matched controls. Parameters used were Tricuspid inflow velocities (Tr-E, Tr-A. Tr-E/A ratio, Tr-DT), Superior and lnferiour Vena Cava velocities, Right ventricular end diastolic dimension and pulmonary artery acceleration time (P accl t). Mitral inflow velocities (MI-E, MI-A, Mi-E/A ratio. MiDT) were measured to assess any correlation between left and right heart diastolic function. The asthma and it’s control group had normal (RV) diastolic parameters. The emphysema group showed significant deterioration in (RV) diastolic function. The two control groups showed age related changes in diastolic parameters and P accl t. Taking into account this age related shit? a significant difference was found in Tr-A and Tr-E/A ratio between the asthma and emphysema groups. There were also significant correlations between a lower P accl t and indices of (RV) diastolic dysfunction. In conclusion, the emphysema group had evidence of right ventricular diastolic dysfunction which correlated significantly with P accl t. In addition there was an age related shit? of diastolic parameters. Diastolic function is preserved in the asthma group, and in comparison to the emphysema group, the latter had an independent effect of irreversible respiratory pathology on right heart function.

Heart, Lung and Circulation

49th Annual Scientific Meeting of CSANZ

2001; 10

DETERIORATION OF LV LONG AXIS FUNCTION ON STRESS ECHO MAY BE A MARKER FOR GLOBAL DYSFUNCTION IN PATIENTS WITH MITRAL REGURGITATION B Haluska*. L Short. P Cain’TH Marwick. Princess Alexandra Hospital, University of Queensland, Brisbane, Qld. In patients with mitral regurgitation, loss of contractile reserve (CR) may be a marker of early LV decompensation. Pulsed tissue Doppler (DTI) has been used to assess long axis LV function and shown to be as sensitive and less load-dependent. We sought to determine if patients with preserved long axis function on stress echo have preserved CR. Methods: 60 patients (20 women, age 58216) underwent cycle stress echo for evaluation of asymptomatic/minimally symptomatic MR (n= 51) or as controls (n=9). Sequential studies were performed in 15 patients with MR and 5 controls. Harmonic 2D images and basal DTI were obtained at rest and stress, and exercise capacity (METS) was assessed using expired gas analysis. CR was defined as an increase in EF over rest (biplane Simpson’s) of >4%. Results: In patients with MR, EF was 63*11% at rest and 63+16% at peak. CR was present in 29 studies. Peak EF in Controls was 75*7%, and in CR+ 75&10% vs 54+15% in CR-. Controls and patients with CR+ showed similar DTI and volume data but differed in resting EF and exercise capacitv _ _ Controls (14) CR+ (29) CR- (37) p (CR+ YS CR-) ,D(CR+ YS Control)

Age 32*9 54t19 62+12 .04 ~001

DTlpeak 16+.03 .13*.03 .10*.03 coo1 NS

Delta DTI .07+.02 .06+.03 .03_+.02 coo1 NS

EFrest 56i9 65+9 62212 NS ,004

ESVpeak 1St6 21+12 46+28 coo1 NS

METS 11*2 5+2 4+2 NS <.OOl

CR could not be predicted by resting EF or LV volume, MPHR achieved or METS, but was related to age, peak DTI velocity and delta DTI. Resting EF was higher in MR patients, probably due to volume loading (Table). In a multiple linear regression, age, resting and peak volumes and peak DTI were predictors of CR (model R= 0.74; p<.OOl) Conclusion: 1. Patients with MR who have CR have similar long axis function as controls. 2. Failure to increase long axis function on stress echo may be a marker for global LV dysfunction.

A81

CLINICAL AND TONOMETRIC ASSESSMENT OF PULSE CHARACTER IN SEVERE AORTIC STENOSIS J.&ha-Navaeam* and L. Amolda. Dept of Cardiology, Flinders Medical Centre, Bedford Park, South Australia Background: The presence of a slow rising carotid pulse is considered to be critical to a diagnosis of aortic stenosis (AS) but this physical sign has not been validated. Methods: Radial and carotid pulse waveforms of 23 patients with severe isolated AS (mean echocardiographic gradient (MEG)> 35mmHg) and 23 control patients were assessed with arterial aplanation tonometer. The time to dominant peak of the pulse wave (tDP) and the maximum rate of rise (dP/dt) were measured. Blinded clinical assessment of carotid pulse alone was performed by one of three cardiologists. Results: 14 out of the 23 patients (61%) with severe AS were assessed as having a definitely slow rising pulse, with 9 being assessed as indeterminate. In the control group 13 (56%) were classed as having normal, 7(30%) were thought to be indeterminate and only 3 (13%) were assessed to be slow rising. (odds ratio of slow rising pulse being AS 9.51; p
A PROPER RANGE OF THE INTERNATIONAL NORMALIZED RATIO FOR LEFT ATRIAL THROMBI RESOLUTION AMONG CANDIDATES FOR PERCUTANEOUS TRANSVENOUS MITRAL COMMISSUROTOMY Silaruks S *, Thinkhamroo B. Tantikosum W, Wongvioauorn C Tatsanavivat l? and Kluneboonkrong V. Department of Medicine, Faculty of Medicine, Khon Kaen University, Thailand. Background: Resolution of left atria1 thrombus (LAT) in mitral stenosis patients, by oral anticoagulation, can enhance the possibility of safely performing percutaneous transvenous mitral commissurotomy (PTMC). However, the proper range of the international normalized ratio (INR) for this purpose has not been established. Objectives: To determine the optimal INR cut-off point for establishing the proper range that best predicts the LAT resolution. Design: A historical cohort study Methods: Between August 1996 and December 2000, 134 consecutive candidates for PTMC, with documented LAT, underwent both transthoracic and transesophageal echocardiographic studies. Multiple logistic regression was used to determine the effect of INR adjusted for other potential confounders. Receiver Operating Characteristics (ROC) curve was used to determine the optimal cut-off point. Results: Of 1791 patient-months, 85 patients (4.7/100 patient-months) demonstrated resolution of LAT(333 INR samples examined, 89.2% exceeded 2.5). The mean+SD of the median INR in the LAT-resolution group was 3.OkO.2 (range 2.3-3.5) while it was 2.2~0.1 (range 1.7-2.5) in the LAT-persisting group. The INR nearly always predicted LAT resolution (area under the RQC = 0.99). The optimal INR cut-off point was 2.5, establishing the INR range of 1.7 to 2.4 and 2.5 to 3.5. This cut-off point yields the highest performance of such prediction ,with the sensitivity 98%,the specificity lOO%, and the positive and negative predictive values 100% and 96%, respectively. Eighteen minor bleeding events were observed -12 in those with an INR< 2.5. A single transient ischemic attack occurred-his median INR was 2.1. Conclusion: The INR of 2.5-3.5 should be recommended as the proper range for successful LAT resolution in candidates for PTMC, with the low bleeding complication.

A82

49th Annual

Scientific

Meeting

of CSANZ

Heart,

Lung

and Circulation

2001; 10

CAN COLOUR DOPPLER MYOCARDIAL IMAGING QUANTIFY ATRIAL DYSFUNCTION L Thomas*l,~~, DYC Leune2a and, 3UCSF, San Francisco, USA, rLiverpoo1 Hospital and ‘Westmead Hospital, Sydney, Australia.

IMPROVED ENDOCARDIAL VISUALIZATION WITH HARMONICS AND CONTRAST AGENTS: DO ALL LV SEGMENTS BENEFIT? lie *I . G .A. Department of Medicine, University of Auckland, New Zealand.

Aim: Atria1 function is clinically relevant but its accurate assessment has been difficult. Colour Doppler Myocardial Imaging (CDMI) has been used to quantify ventricular contraction. We hyphotesised that CDMI could be used to study atria1 contraction as a measure of atria1 function.

Second harmonic imaging and LV opacification using intravenous contrast have been shown to improve endocardial definition in patients with suboptimal apical echocardiographic views. The aim of this study was to evaluate the effects of harmonics and contrast on LV endocardial visualization and to determine whether this improvement was uniform throughout the LV or specific to certain segments. Methods: 61 subjects (30 healthy controls and 31 with CHF) were included in this study. Subjects were not pre-selected on the basis of suboptimal image quality. Apical 4 and 2 chamber views were obtained using fundamental gray scale imaging (FUND), second harmonic imaging (HAR), harmonics with contrast agent (Levovist, 4gr bolus) (CONT) and contrast with dual-triggered (end-diastole, end-systole) imaging and power Doppler (POWER). 732 segments were graded for visualization (O=not seen, l=visualised, 2=well visual&d). Results: All 3 methods improved the visualization of segments compared to FUND (all ~~0.05) and there was no difference between HAR and CONT:

Methods: We studied a total of 42 patients: 21 patients were normal healthy volunteers (Grp l-NSR) and 21 chronic AF patients (Grp2-AF/SR) imaged within 4 hours of successful cardioversion to sinus rhythm. Using CDMI, mean peak velocities of atria1 contraction in late LV diastole were measured from annular, mid and superior segments of lateral and septal walls of left atrium (LA) and right atrium (RA) in the apical 4 chamber view and from annular, mid and superior segments of the anterior and posterior walls of the LA in the apical 2 chamber view. Results: Mean peak velocities of atria1 contraction (AC) were highest in the annular segments and lowest at the superior segments. AC was higher in the lateral walls for both LA and RA vs the septum in both groups. Individuals in Grp 1 had significantly higher AC at the annular and mid segments compared with Grp 2. No significant difference was noted at the superior segments between the two groups.

Grpl

Grp2

(NSR)

(AF/SR)

RA -8.5+2 -4.4*1 -1.4r.8

Wall -4.3+3* -2.5+2* -.9+.7

‘3.~2

Grpl

tAF/SR)

(3~2

(NSR)

(NSR)

=P -6.5*1 4.3+1 -.9+.6

turn -2.9*2* -2.2*1’ -.5*.4

LA -6.4k2 -5.922 -.9?.6

(AF/SR) Wall -2.2+2* -1.6rl’ -.5+.4

Grpl

Number of Lq?pents not seen

FUND

HAR

CONT

POWER

87 (11.9%)

34 (4.6%)

28 (3.8%)

61 (8.3%)

With FUND, the basal and mid anterior and lateral walls were least well visualised (see table). All 4 segments improved with both HAR and CONT, and although more segments were seen with CONT, this was not statistically different from HAR: Sek?ments not &alized (no.) basal anterior

FUND

HAR

CONT

POWER

21 (34.4 %)

‘p
basal lateral

16 (26.2 %)

Conclusions: 1) CDMI of the atria1 wall could be used to quantify atria1 contraction; 2) AF results in atria1 dysfunction even after successful cardioversion as demonstrated by decreased atria1 contraction velocities.

mid lateral

14 (22.9 %)

lO(16.4 %) 8 (13.1 %) 5 (8.2 %)’ 4 (6.6 %)

8 (13.1 %) 5 (6.6 %) 3 (4.9 %Y 2 (3.3 %)

21 (34.4 %) 18 (29.5 %) 3 (4.9%) 0 (0 %)

Annular Mid Superior

DOES HARMONIC IMAGING OR CONTRAST IMPROVE THE REPRODUCIBILITY OF ECHOCARDIOGRAPHIC MEASUREMENT OF LV EJECTION FRACTION? G.A. N., Department of Medicine, University of Auckland, NZ. Echocardiographic EF is often used as a guide to therapy and to monitor changes with treatments in congestive heart failure (CHF). Current echo methods am subject to image quality and have limited precision. Both harmonic imaging and contrast improve endothelial definition in patients with sub-optimal images. The current study aimed to determine whether reproducibility was sufficiently reduced with these imaging modalities to warrant wider applicability. Methods: On 2 different days, 56 subjects (29 CHF, 27 normals) had apical 4 and 2 chamber views recorded with fundamental imaging, harmonic imaging, harmonics with contrast agent (Levovist, 4g) and contrast with triggered (end-diastole, end-systole) imaging and power Doppler (POWER). End-diastolic volume (EDV) and end-systolic volume (ESV) were measured offline using Simpson’s method and EF calculated (3 cycles). One observer measured both davs and one dav twice, another observer measured one day1 only.1 Results: LVEDV, ml LVESV, ml EF, % <* <. 1

Fundamental 131.3 * 74.7 69.5 + 67.1 54.2 + 15.6 ast m a

Re mducibili

:

IntraObserver InterObserver Day to Day

AEF LOA AEF LOA AEF LOA LOA = limits of agreement, A

Harmonics

Contrast

131.3 k 77.7 67.9 i- 66.8 55.5 + 15.4

140.9 * 83.2* 69.5 zt 71.9 58.3 + 16.1’

Fundamental 1.54 -5.9,2.82 1.66 -3.8.7.14 -1.04 -8.49,6.41 EF is expressed as

Harmonics - 0.99 -5.37,3.39 1.67 -4.91,8.25 - 2.01 -9.29,5.27

Contrast _ 0.92 -6.885.04 - 0.32 -6.84, 6.2 1.68 -8.3,6.1

POWER 124.9 + 61.3 68.2 + 57.1 51.2 r 15.5 POWER 0.91 -5.48,3.66 - 2.92 - 8.6,2.76 -1.1 -5.32.8.68

mean

Conclusion: No statistical differences were seen for reproducibility between the methods, Thus, no advantage was detected for harmonics or contrast. However, when compared to non-contrast fundamental and harmonic imaging, contrast overestimated EDV and EF and thus may represent an important source of misclassification bias.

mid anterior 13 (21.3 %) * p
Conclusions: Both harmonics and contrast improve endocardial visualization, compared with fundamental imaging. The increase in the number of wall segments visualised with contrast was not statistically significant, but may be clinically relevant. Importantly, not all LV segments are visualized equally, or have the same potential for improvement, both of which are dependent upon the individual location of the segments.

THE LONG TERM EFFECT OF ORAL PERINDOPRIL 4-8 MG AND AMLODIPINE 5-10 MG ON AMBULATORY BLOOD PRESSURE (ABP) AND CARDIAC STRUCTURE IN SUBJECTS WITH PRIMARY ESSENTIAL HYPERTENSION. G.L. L. De ar -Alfred Baker Medical Unit, Baker Medical Research Institute, Melbourne. The aim of this study was to compare the effect of 12 months treatment with perindopril (I’) with the amlodipine (A) on ABP and on cardiac structure in patients with mild-moderate hypertension. Male or female subjects, 18-65 years, with supine diastolic (DBP) > 95 mmHg, having been untreated or previously ceased antihypertensive therapy treatment. Following a placebo runin of 4 weeks, subjects were randomised in a double blind manner to (l’) 4 mg or (A) 5 mg orally. The medication dose was titrated, being increased to (P) 8 mg or (A) 10 mg daily if BP was not controlled. 36 subjects participated and 41.2% and 10.5% were female in the P and A groups respectively (p = 0.034). The day-time ABP values (mmHg) prior to the run-in period were (P: 154/100, A: 160/100, p = ns). At 1 year they were (P: 133/86 (-21/-14) mmHg, A: 137/86 (-23/-14) mmHg; all p < 0.001 for the over time analysis)). There were no significant between group differences at week 52. Prior to the run-m period posterior wall thickness (PWT), left ventricular mass (LVM), WT ((interventricular septal wall thickness (IVS) + PWT)/2) and LVM index (LVMI) were significantly lower in the P group (p = < 0.05). On the intention to treat analysis LV internal diastolic diameter (LVIDD), IV’S, PWT, LVM, LVMI and WT all decreased significantly over time (p < 0.001, except for LVIDD in the A group where p < 0.01). This degree of decrease did not differ significantly between the groups on a repeated measures analysis including the 27 subjects who had the tests at both times. P and A treatment for 1 year, lowered ABP values and decreased heart size in subjects with mild-moderate hypertension, There were no significant differences between treatment groups in these effects.

Heart,

Lung

and Circulation

2001;

49th

10

Annual

Scientific

Meeting

of CSANZ

A83

SPINAL EXCITATORY AMINO ACID RECEPTOR-MEDIATED PRESSOR RESPONSES ARE ATTENUATED BY NITRIC OXIDE AND ARE INDEPENDENT OF GUANYLATE CYCLASE LF Amolda*. IB Minsonl& Dl M&trick. Dept. Cardiology, Royal Perth Hospital, Perth, WA; ’ Dept. Medicine, Flinders Medical Centre, Bedford Park, SA.

VALIDITY OF FOURIER DOMAIN ARTERIAL TRANSFER FUNCTIONS FOR THE ESTIMATION OF AORTIC SYSTOLIC BP FROM RADIAL BP WAVEFORMS. SA [email protected]+, DB Tavt, IT Meredith. ID Cameroni, Cardiovascular Research Centre, Monash University, Monash Medical Centre, and La Trobe Universityt, Melbourne.

Nitric oxide (NO), synthesised from L-arginine by NO synthase (NOS), mediates endothelium dependent vasodilatation and acts as a neurotransmitter. NOS has been identified in most sympathetic preganglionic neurons in the spinal cord, but its function at this site is not yet established. We have previously shown that the NOS inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME), amplifies the pressor responses elicited by intrathecal (i.t.) injection of the excitatory amino acid agonist, N-methyl D-aspartate (NMDA). Thus, endogenous synthesis of NO in the spinal cord limits the pressor response to stimulation of spinal NMDA receptors. Most of the known biological effects of NO are mediated by activation of soluble guanylate cyclase, although actions that are independent of guanylate cyclase are now also recognised. In this study we have used a soluble guanylate cyclase inhibitor, lH-(1,2,4)oxadiazolo(4,3-a)quinoxalin-l-one (ODQ), to determine if the effect of NO to limit the pressor response to i.t. NMDA is mediated by soluble guanylate cyclase. In experiments on anaesthetised rats, we determined whether intrathecal (i.t.) administration of either ODQ (IOOmM, 1OpL) or L-NAME (lOOmM, IOpL), affected the response to stimulation of spinal NMDA receptors by NMDA (10 PM to 1OOmM in 1OpL i.t.).

It has been hypothesized that central aortic BP may be a useful clinical index. The use of arterial transfer functions (TF) has been promoted as a means of deriving central BP waveforms not usually accessible by non-invasive means. To investigate this technique we simultaneously recorded invasive central aortic and non-invasive radial (MillalB [email protected] tonometer) BP waveforms in 78 subjects (61M:17F) undergoing elective coronary procedures (Chart for [email protected], 200Hz). The data was applied to a single-input/single-output model for calculation of a TF. Individual TFs were derived for each subject by 2 methods: firstly, from a 4000-point sequence (256 point sliding window, Welch’s averaged periodogram method [email protected]) (ITF,), and secondly from an average cycle obtained by initially segmenting the pressure time sequence into individual cardiac cycles (iTF,). Ensemble averaged TFs were obtained for the group as a whole (eTF,, eTF,) and for each sex individually (male=mTF,, mTF,, female=fIF,, ffF,). Reverse transformation was performed using each TF. Only the first 14 harmonics were included in all analysis. Point-by-point comparison of original and TF, reconstructed waveforms using standard error of the absolute difference (sed) revealed a borderline significant difference between iTF, and eTF, (mean difference=-0.67mmHg, sed= 0.33, p= 0.05, paired t-test), however there was no difference when gender specific TF,s were compared by ANOVA. Central SBP was derived (dcSBP) using both estimates of TF. The mean difference between measured and dcSBP using iTF, was 0.43 (sed=3.85) mmHg compared to 2.6mmHg (0.83) with eTF, (p=ns). This difference tended to be greater in females than males but did not reach significance either for direct or inverse application of gender-specific TFs (mean difference 5.81 (0.96) mmHg for mTF, in males, -30.44 (5.2) mmHg for fTF, in females). Using eTF, the mean difference between measured and derived cSBP was 0.68 (0.77) mmHg, with no gender effect (p=O.22). Good group agreement between mean measured and derived cSBP was seen in this large cohort. Considerable individual scatter was apparent with both average and individual TFs (95% limits of agreement f 66,6mmHg, iTF,, Bland Altman). We conclude that further experience in large groups is necessary to assess the utility of TFs to derive cSBP in individual subjects or particular patient groups, in particular with respect to gender, age, and risk factors.

Blood pressure tmmHg) after increasing ODQ or L-NAME (~6 per group) NMDA alone DOW Control 55 i 2.6 Vehicle 55 + 2.6 10~M 57+24 100wM 6251.X ImM 76 i 5.1 1OmM 123 f 10 1OOmM 160 + 10

doses of NMDA NMDA +ODQ 60 i 3.1 62 i 2.7 63 i 3.8 71 i 5.5 90 i 9.4 136+12 176k5.1

alone OI in combination

with

NMDA +L-NAME 67+4 70+3a 155 * 13 162514 166215 184 i 8.9 192 i 4.8

NMDA increased blood pressure in a dose dependent manner (F,,,,= 129, P
THE EFFECTS OF PHYSIOLOGICAL STRESSES ON VASCULAR MEABILITY. SA [email protected]+. IT Meredith. Cardiovascular Research Monash University, Monash Medical Centre, Melbourne. USE OF THE TANGO AUTOMATIC BLOOD PRESSURE DEVICE DURING SUPINE EXERCISE: COMPARISON WITH MANUAL AND INVASIVE BRACHIAL BLOOD PRESSURES. J D Cameron*. I Stevensoni, Et, B A K&well. B P McGratht and AM Dart. Baker Medical Research Institute, $Alfred Heart Centre, and tMonash University Melbourne Australia Accurate registration of brachial blood pressure during exercise is an important component of diagnostic cardiological testing. Patient movement, mechanical vibration, artifactual sounds and observer variability make observation using standard manual techniques problematic. The [email protected] stress test blood pressure monitor (SunTech Medical Instruments, NC, USA) aims to overcome these issues by performing automated brachial sphygmomanometry incorporating ECG-gated detection of K-sounds and proprietary noisereducing signal processing We performed an initial investigation of the device in 5 fit, young males (21 - 26 years, mean 25.2) performing supine exercise on an electronically braked bicycle ergometer with 30 W increments every 4 minutes. BP was recorded at regular intervals from the right arm using the Tango device with simultaneous (blinded) manual measurement by 2 trained observers. Continuous beat-to-beat invasive BP was recorded from an indwelling brachial catheter in the contralateral arm (CVMS cardiovascular monitoring system, McPherson Scientific, Australia). We subsequently employed the same protocol (without manual BP) during 10 stress-ECG tests using the modified Bruce protocol in our chest pain evaluation clinic. In both environments the device successfully tracked invasive with typical results as shown. Maximum differences were between -7.2% and -14% and tended to occur at maximum systolic pressure and heart rate. Apparent discrepancies between invasive, manual and automatic measurements were within a useful clinical range. The Tango device appears tolerant to supine and tredmill exercise and to provide reliable automatic BP assessment,

PERCentre,

The endothelium is now known to play a central role in the control of many vascular functions including vascular tone, thrombosis and permeability. Changes in vascular tone occur rapidly in response to differing physiological stimuli, including mental and physical stresses, with different responses in diseased and healthy arteries. We sought to examine the effects of acute physiological stresses on vascular permeability as reflected by changes in plasma colloid osmotic pressure @‘COP), a potential index of vascular permeability, which occur in healthy humans in response to the physiological stresses of mental arithmetic and a cold pressor test. Blood was obtained from the antecubital fossa of 20 healthy volunteers after 20 minutes of supine rest and immediately following a physiological stress. Of the 20 subjects (7 male: 13 female), ages 31.3 f 11.16 years (mean + SD), 10 performed a mental arithmetic task, serial subtraction of 7’s from 500, and 10 underwent a cold pressor test, l’/z minutes immersion of the contralateral forearm in iced water. Plasma samples were analysed with an Osmomat 050 Colloid Osmometer with a 1OKDa molecular weight cut-off membrane and 0.9% saline as the reference solution. Mean resting PCOP was 25.88 f 126mmHg. There was a significant rise in PCOP following the stress to 26.27 + 1.13mmHg (pO.7). Blood pressure rose with both stresses (p
A84

49th

Annual

Scientific

Meeting

AMIODARONE DOES NOT HAVE ACTION IN HUMANS. D. HaikerwaP and A. Dart. Baker Medical Hospital, Melbourne, Australia

of CSANZ

A

Heart,

SYMPATHOLYTIC

Research

Institule/Alfied

Introduction: Previous experiments in animals demonstrated a novel sympatholytic action of acute intravascular amiodarone (AM). The aim of this study was to determine if this action also occurred in humans. Methods: 12 male volunteers performed handgrip for 10 minutes before and after 300mg intravenous AM over 60mins. The effect of handgrip was determined from changes in blood pressure, heart rate and cardiac noradrenaline (NA) spillover. Changes in cardiac spillover of dihydroxyphenylglycol (DHPG), the metabolite of NA was measured during the AM infusion. The electrophysiological effects of AM were determined from changes to the A-H intervals during right atria1 stimulation (100bpm). Results: Handgrip resulted in increases in heart rate (63 * 2 to 84 f Sbpm and 65 f 3 to 84 + 4bpm), systolic blood pressure (14 1 zt 4 to 179 + 6 mmHg and 140 + 4 to 179 ? 7 mmHg) and cardiac NA spillover (11942 f 3832 to 44279 f 13388 pg/min and 17327 f 4133 to 55514f 10740 pp/min) pre and post AM infusion (~~0.02 in all groups). There was good correlation between increases in cardiac NA spillover and heart rate (r2= 0.86) and systolic blood pressure (r2= 0.87). AM produced a measurable electrophysiological effect with a significant increase in the A-H interval (95.5 + l8ms to 107.8 ?r 20ms, pcO.02). There was no difference in haemodynamic or NA response to handgrip before or after the AM infusion. Over the 60min AM infusion DHPG cardiac spillover did not change. Discussion: Despite intravenous AM producing an electrophysiological response there was no attenuation in haemodynamic and NA response to handgrip, neither was there any increase in DHPG production. Conclusion: Acute intravenous AM does not exert a sympatholytic action in humans.

A STUDY OF THE EFFECTS OF ACIDOSIS ON FLECAINIDE INDUCED BLOCKADE OF KV4.3 CURRENTS S.Sinearavar’. H. Tie, 1. Bursill. K. Wvse. A. Bauskin, W. Wu. S.Breit. T. Camubell. Department of Medicine, Centre for Immuno1ogy and The Victor Chang Cardiac Research Institute, St. Vincent’s Hospital, Sydney Proarrhythmia is likely to be the effect of drug binding interacting with a heterogeneous series of conditions that favour proarrhythmic results over antiarrhythmic effects. One such condition is illustrated by flecainide proarrhythmia which is more likely to occur with coronary ischaemia. The reasons for this are unknown however animal studies have implicated a prominent epicardial transient outward potassium current I,, in the genesis of flecainide-induced ventricular arrhythmias. We hypothesised that acidosis may modulate flecainide induced blockade of the transient outward current and result in a relatively preserved Ito. We used Kv4.3, the gene responsible for the majority of Ito in humans to test our hypothesis. Methods: Kv4.3 was stably transfected in Chinese Hamster Ovarian cells (CHOKI). Standard whole cell patch clamp techniques were used. Paired experiments using different doses of flecainide were compared in bath solutions with a pH of 7.4 and a pH of 6.0.Results: Flecainide induced blockade of Ito was significantly decreased in acidosis. Half maximal inhibition (IC,) at pH=7.4 was 7.5+ 1.2 uMol/l and at pH=6.0 was 152.2+ 1.1 pMol/l (P
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MIANSERIN, A TETRACYCLIC ANTIDEPRESSANT, BLOCKS HERG: IMPLICATIONS FOR PROARRHYTHMIA. H. lie*. S. Smparavar. 1. Bursill, K. Wvse. A. Bauskin. S.N. Breit. T.I. Camobell. Department of Medicine, University of NSW, Centre for Immunology, and Victor Chang Cardiac Research Institute, St. Vincent’s Hospital, Sydney. Many psychiatric drugs, such as antipsychotics and tricyclic antidepressants, can impair cardiac repolarization (which manifests as QT prolongation) to such a degree that potentially life-threatening arrhythmias, such as torsades de pointes, may occur. Our previous work have established that the cellular basis underlying this proarrhythmic effect by several of these agents is blockade of HERG, an important cardiac potassium channel. Mianserin is a tetracyclic antidepressant. The effect of tetracyclics on HERG has not been previously reported. We sought to determine mianserin’s proarrhythmic potential by studying its effects on HERG stably transfected into Chinese Hamster Ovary (CHO-Kl) cells. We used the whole cell configuration of the patch-clamp technique. Results: Mianserin blocked HERG tail currents at 60mV following a voltage step to +30 mV in a concentration-dependent manner, with an IC,, of 14.2 + 1.3 uM and a Hill Slope of -2.8. The voltage required for half maximal activation, Vi,,, was shifted from -19.4 ? 0.3 mV under control conditions to -22.8 + 0.8 mV after 30 mM mianserin (p=O.O03, n=S). Block by mianserin 30 uM displayed voltage-dependence between 50 mV and +30 mV. Activating currents elicited during incremental voltage steps from -80 mV to between -50 and +30 mV were inhibited by 30 i.tM mianserin at potentials above -30 mV but there was no block at more negative potentials. Conclusion: Mianserin inhibits HERG channels with preferential binding to the open/inactivated channel states. This tetracyclic antidepressant thus possesses direct electrophysiological effects similar to other QT-prolonging drugs. However, these effects are observed at concentrations several-fold higher than therapeutic plasma concentrations (-0.4 mM) and, in part, accounts for the rarity of cardiac complications observed clinically with this agent. Nevertheless, in conditions of impaired drug elimination, after overdose or concurrent administration of other QT-prolonging drugs, attention to the proarrhythmic potential of mianserin appears warranted.

PERHEXILINE IMPROVES PLATELET cGMP RESPONSIVENESS TO NITRIC OXIDE IN PATIENTS WITH ACUTE CORONARY SYNDROMES. Y.Y.Chirkov*. A.S.Holmes, T.M.Steoien and l.D.Horowitz. Cardiology Unit, Queen Elizabeth Hospital, University of Adelaide, South Australia. Resistance of platelets to the anti-aggregatory effects of nitric oxide (NO) donors such as nitroglycerine and sodium nitroprusside (SNP) occurs in patients with stable angina pectoris’ and acute coronary syndromes (ACS). This NO resistance reflects both scavenging of NO by neutrophil-derived superoxide radical (OJ, as well as partial inactivation of platelet soluble guanylate cyclase’. Perhexiline (l’ex), an anti-angina1 agent which also inhibits carnitine palmitoyltransferase-1, limits NO resistance, but the mechanism of this improvement is uncertain. We now investigated whether treatment with Pex modifies (1) platelet cGMP responsiveness to NO and (2) blood levels of Or-. Blood samples were obtained from 24 patients (16 men and 8 women, aged 70.5+9.4[SD] yrs) with ACS before and 3-5 days after initiation of treatment with Pex. ADP-induced platelet aggregation and its inhibition by SNP were determined (impedance aggregometry) in whole blood (WB) and platelet-rich plasma (PRP). Intraplatelet cGMP content was assayed by RIA, and WB 0, levels by lucigenin-derived chemiluminescence (LDCL). In accordance with our previous studies, inhibition of aggregation by SNP increased after treatment with Pex, both in WB and PRF (Table); basal aggregability did not change. This was paralleled by an increase in the extent of intraplatelet cGMP elevation by SNP (Table); basal cGMP levels did not change. There was a strong correlation between the increases in cGMP-elevating effects of SNP and its anti-aggregatory effects both in PRP (R=O.77, p=O.O4) and WB (R=0.87. o=O.Ol). 0; levels did not chanee after Pex treatment. SamplingInhibition

of aggregation by SNP (% of control) PRP

Baseline Pex

20+5 42*7’*

cGMP elevation by SNP (% of control)

oz(mV of LDCL)

149tlO

37*5

190+15*

39+6

5&5”

‘p
Conclusion: Pex-induced reversal of platelet NO resistance (1) occurs both in I’RP and WB, and (2) is associated with improved platelet cGMP production in response to SNP, but not with any change in WB 0; content. Thus, Pex limits NO resistance by restoring platelet guanylate cyclase responsiveness to NO. i) Chirkov

et al. 1999, Circulation

100:129-134.

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PATTERNS OF CORONARY ARTERY MOVEMENT AND THE OCCURENCE OF LESIONS IN THE LEFT CORONARY SYSTEM. Tsuyoshi Konta, JHN Bett*. Department of Cardiology, Prince Charles Hospital, Queensland, 4032, Australia It has been postulated that mechanical stress may provoke endothelial injury and the development of atherosclerotic lesions in coronary arteries. We studied 100 consecutive angiograms of the left coronary artery and classified the patterns of movement in six segments from the anterior descending (LAD) and three to five segments from the circumflex artery (LCx). The occurrence of lesions 2 50% diameter and a pattern of compression (in which segmental length was shortened) were both more common in the LAD than in the LCx (figure). There was a very strong association between the pattern of compression and the presence of lesions (62% of segments with compression v 5% of segments with other patterns of movement, p< 0.0001). This suggests that there may be a causal relationship between the pattern of compression with movement in segments of the left IDI coronary arttery and the occurrence

disease.

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DESIGN, PATIENT CHARACTERISTICS AND RUN-M RESPONSES TO TREATMENT IN FIELD: A LARGE-SCALE TRIAL OF FENOFIBRATE EFFECTS ON CARDIOVASCULAR DISEASE IN TYPE 2 DIABETES. EM Belier*, P Barter. J Best. RJ Simes. P Younp R Scott. M-R Taskinen and A Keech for the FIELD Grout. NHMRC Clinical Trials Centre. Svdnev. The FIELD study is a random’ised controlled trial to determine whkthe;longterm treatment using fenotibrate to increase HDL cholesterol and lower triglycerides reduces CHD mortality. A total of 9795 patients with type 2 diabetes (SO-75 years), with total cholesterol levels between 3.0 and 6.5 mmol/L have been randomised to either fenotibrate (200 mg micronised daily) or placebo for a follow-up period of not less than 5 years on average. Baseline characteristics Characteristic Age >= 65 years

of patients randomised to the FIELD study Males (63%) Females (37%)

42%

Total

38%

41%

~~~~~i 1 i Prior cardiovascular

disease

Changes in lipids during a 6-week active run-in period prior to randomisation compare favourably with those seen in the low-HDL intervention trial (HIT), which reported a significant reduction in CHD events in mostly non-diabetics. Absolute

(mmol/L)

trT;ialcholesterol LDL cholesterol HDL cholesterol Triglycerides

and percent change in lipids in the FIELD and HIT studies FIELD active run-in HIT ( I2 months)

-0.6 (-10.6%) -0.4 (-10.4%j 0.06(6.0%) -0.56(-24.5%)

-------I -0.2 (-4.0%) 0.0 (6.0%) 0.05 (6.0%) -0.58 (-3 1.0%)

The FIELD study will help to clarify the indications for lipid modifying treatment and in particular modification of HDLc and TG using a fibrate in diabetes, in both primary and secondary prevention ofcardiovascular disease.

ACCURACY OF DIAGNOSING CORONARY ARTERY DISEASE UTILIZING BRACHIAL ARTERY FLOW-MEDIATED DILATION. E.S. Biwelsen ST. Duff?. N. Gokce. M. Holbmok. T.F. Keanev, Ir.. T.A. Vita. Boston University School of Medicine, Boston, MA, USA.

TREATMENT CORONARY

Background Endothelium-dependent, bra&al artery flow-mediated dilation is impaired in patients with coronary artery disease (CAD), prompting speculation that examination of this response might have clinical utility as a screening tool. The aim of this study was to determine whether this non-invasive measure of brachial artery endothelial function predicts the presence and extent of CAD. Methods and Results Brachial artery flow-mediated dilation was assessed in 574 participants (188 patients with symptomatic, angiographically proven CAD and 386 volunteers without clinical evidence of CAD). Flow-mediated dilation was assessed in response to reactive hyperemia, with the occlusion cuff positioned on the upper arm, using high-resolution vascular ultrasound. These results were related to the presence and extent of CAD. Patients with CAD demonstrated lower brachial artery flow-mediated dilation than participants with no history of CAD (6.8+4.8% vs. 11.3*6.4%, P
Background: The treatment gap is the difference between the treatment recommended on the basis of clinical trials and the treatment that occurs in the

GAPS IN PATIENTS WITH HEART DISEASE IN MELBOURNE

2000. j&J, Vale*. M.V. .lelit&J,D. group, Melbourne, Australia.

Best.

ESTABLISHED

1997-1998; On behalf of the COACH

1999study

community. International studies have indicated that only a minority of patients with coronary heart disease (CHD) have achieved targets for secondary prevention or are even on treatment. There are no figures available for

Australia. Methods: We are presenting the results from the control groups of 2 intervention studies into coaching the patient with CHD to achieve target lipid levels. The 460 patients who completed the 2 studies in the usual care group represent a full spectrum of patients from different metropolitan areas, socioeconomic groups and rural Victorians. Furthermore, they represent the periods 1997-1998 and 1999-2000. Results: The lipid studies include 112 patients from 1997-1998 and 348 patients in 1999-2000. All the other risk fa&rs were derived from 1999-2000. Risk Factor Target 1 No. on Treatment 1 No. Meeting [email protected] Total cholesterol ‘97-98: 67(60%) I5 (14%) I

Conclusion: A significant treatment aao exists in Victorian Datients with established corona< heart disease. Tbe’treatment gap compares well with

international surveys and, at least in the lipid area, is improving.

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EPIDEMIOLOGICAL MODELLING AND ITS USE IN PREVENTIVE CARDIOLOGY D Liew’. 11 McNeil. A Peeters. S Lim. T Vos. R Wolfe, S w Department of Epidemiology and Preventive Medicine, Monash Medical School, Alfred Hospital, P&ran, Victoria 3181. Clinical trials of preventive therapies in cardiology provide relatively precise information about the efficacy of interventions but only crude indication of the most suitable candidates for such interventions. Epidemiological modelling combines data from demographic registers with evidence from observational epidemiology and clinical trials to assist in optimising preventive strategies. It represents a means of precisely targeting therapies to those for whom these are most safe and cost-effective. It also provides the tools to present information about risks and benefits of therapies to patients in a more explicit and understandable fashion than has been previously available. Due to the availability of extensive data in this field, cardiology lends itself particularly well to epidemiological modelling. As an example, we model the lifetime effects of primary prevention with antilipid therapy in the current Australian population. Data are taken from the West of Scotland Coronary Prevention Study, which reported a 22% relative reduction in risk of mortality associated with pravastatin. The results of modelling confirm that absolute gain in survival is greatest for those with highest pre-treatment risk. However, they also indicate that even among those with the most adverse risk profile, significant survival benefit is not apparent before 65 years in males and 75 years in females. Such notions have considerable implications for the targeting and timing of treatment, but are not apparent from the results of clinical trials alone. Factors related to costs and adverse effects of treatment are also important, and can be easily incorporated into epidemiological modelling. Faced with limited resources, it is necessary for clinicians and policy-makers to determine objective and equitable ways of targeting preventive therapies in cardiology. Since clinical trials will only ever be conducted in a limited number of clinical settings, epidemiological modelling is required to extrapolate the results to the larger community and within a lifetime context. Analysis of the impact of various preventive strategies should only be done in the broader context of competing mortality and morbidity risks, demographic change, and varying disease trends. THE CORONARY HEART DISEASE (CHD) PREVENTION MODEL: A METHOD FOR COMPARING THE COST EFFECTIVENESS OF INTERVENTIONS FOR CHD BY PERCENTILES OF INTEGRATED RISK. : il. Epidemiological Modelling Unit, Department of Epidemiology & Preventive Medicine, Monash Medical School, Alfred Hospital, Prahran, Victoria, Australia, 3181 Coronary heart disease (CHD) is one of the leading causes of mortality and morbidity in Australia. There is an increasing range of preventive interventions which reduce the risk of CHD, including individual measures, e.g. lipid-lowering pharmacotherapy as well as population-wide measures, e.g. health promotion. With health expenditure in Australia growing, there is increasing pressure to justify choices in spending on health services. The CHD Prevention Model provides a method for comparing the cost effectiveness of preventive interventions for CHD. It further allows the targeting of treatment to subgroups that are most at risk of CHD. Using this method, a comparative analysis of the cost-effectiveness (CE) and absolute health impact of targeted primary prevention with HMG-CoA reductase inhibitors (statins) and population-wide health promotion strategies to reduce cholesterol will be presented. The CHD Prevention Model has been described in detail elsewhere’. Briefly, the model integrates a multivariate risk equation for CHD from the Multiple Risk Factor Intervention Trial (MRFIT) with Australian risk factor prevalence and mortality data. This allows the prediction of the future incidence of CHD in the Australian population stratified by percentiles of CHD risk. Efficacy, costs of the interventions and cost of illness were based on a combination of clinical trial results and estimates of Australian costs (adjusted to 1998 dollars). Uncertainty for a range of parameters in the model was determined by simulation techniques. The results of the analysis confirm that widespread primary prevention with statins is prohibited by cost. However, the relative CE of statins increases if therapy is targeted at older age groups and higher risk percentiles. For example, for men in the top 5 percentiles of CHD risk (i.e. those at greatest risk), lifetime statin therapy is only cost-effective if targeted at those aged 2 55 years (given a CE cutoff of AUS$50,000 per life year saved). The comparative analysis of statins with the health promotion campaign demonstrates that while the health promotion campaign is generally more cost-effective, it has a smaller absolute health impact. The CHD Prevention Model can provide policy makers with a useful tool not only in assessing the cost-effectiveness of interventions, but also in targeting therapy to sub-groups where primary prevention is most appropriate. l McNeil, JJ, Peeters, A, Liew, D, Lim, S, & Vos, T. A model for predicting the future incidence of coronary heart disease within percentiles of coronary heart disease risk. J of Cnrdiozmc Risk. 2001;8(1):31-38.

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USE OF A NATIONAL DIABETES MELLITUS DATABASES AS A RECRUITMENT STRATEGY FOR A LARGE-SCALE MULTINATIONAL CHD INTERVENTION TRIAL &R&h&$, C Lintott. E Belier, P Colman, P 1, t ‘w IM‘ s A Keech for the FIELD Study. NHMRC Clinical Trials Centre, Sydney, Australia The FIELD study is a large-scale randomised controlled trial of the effects on coronary mortality of long-term HDL cholesterol and triglyceride modification using comicronized fenofibrate 300 mg daily versus placebo among 8,000 individuals aged SO-75 years with diabetes. After 18 months of recruitment using traditional strategies including searching hospital and clinic databases and referrals to the study by other doctors for identification of potentially eligible patients in more than 40 clinical sites, these sources of patients had mostly been exhausted with less than half of the target study population recruited. In Australia, an opportunity arose to access a National Service Register of over 450,000 individuals with diabetes under the auspices of Diabetes Australia. In New Zealand, access to a similar Register was offered. Ethics approval was obtained from government health departments to access the databases. Both databases were matched for eligible age and geographical location to a FIELD clinic site. lnvitees were asked to return a reply-paid card if interested. Withii a month, recruitment in both countries increased substantially, with responders accounting for more than 50% of new recruits. Mean I-week

screening rates before and after Register mailouts. Australia New Zealand Before mailout 63 veer week 28 per week After Mailout aa her week 63 per week

Overall 91 per week 151 per week

In conclusion, the use of large community databases can provide an important source of subjects pre-screened for large-scale clinical trials. Staged mailouts can provide an on-going source of potential subjects to maintain recruitment according to each clinic sites’ maximum capacity.

HEPARIN USE IN ACUTE CORONARY SYNDROMES BEFORE AND AFTER IMPLEMENTATION OF AN EVIDENCE-BASED PROTOCOL J.E. .E. everill Centre for Heart & Chest Research, Department of Medicine, Monash University and Centre for Clinical Effectiveness, Monash Medical Centre, Clayton, Victoria. Heparin is recommended for treatment of patients with acute coronary syndromes based on data from randomised clinical trials. However, little information is available about the translation of heparin trial data into clinical practice. Further, it is unclear whether the appropriateness of heparin use can be improved through education and the use of evidence-based protocols. Accordingly, this study had 2 aims: (1) to audit the use of heparin in a coronary care unit in patients admitted with chest pain with respect to patient selection and duration of heparin administration and (2) to determine the effects of the introduction and implementation of an evidence-based protocol on heparin use. Patients were defined as high risk if they had ischemic chest pain and had one or more of the following: diagnostic ECG changes, abnormal cardiac enzymes, or a prior history of coronary artery disease. A duration of heparin therapy of 48 hours was considered the minimum acceptable for patients who did not undergo early invasive managment. Heparin use was audited retrospectively over a 6 month period and then again following introduction of and education in an evidence-based protocol which specifically described risk assessment and the recommended duration of heparin therapy. RESULTS: In the retrospective audit of 216 patients with chest pain, 144/148 (97%) high risk patients received heparin, but only 45% of these patients received heparin 248 hours, while 54/67 (81%) of low risk patients also received heparin. After introduction of the protocol, in 264 patients with chest pain, there was no change in the use of heparin in high risk patients at 152/159 (96%) or the percentage of patients having heparin 248 hours (58%). However, there was a siginificant reduction in the frequency of heparin use in low risk patients to 58/91 (64%, p=O.O2). CONCLUSION: These results suggest that heparin is being commenced appropriately in the majority of patients at high risk of ischaemic events, but that it is being used inappropriately in some low risk patients and that the majority of high risk patients are not receiving heparin for the recommended duration of time. Introduction of an evidence-based protocol resulted in only minor improvements in heparin use.

Heart,

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INFARCT SIZE, HAEMODYNAMIC CHANGES AND CIRCULATING HORMONE LEVELS IN THE FIRST HOUR AFTER INFARCT IN CONSCIOUS RATS DI McKitrick*. IB Minson~ and LF Amolda. Dept. Cardiology, Royal Perth Hospital, Perth, WA; 1 Dept. Medicine, Flinders Medical Centre, Bedford Park, SA. The myocardial infarction (MI) model in the rat is the most widely used model of heart failure. In the chronic phase atria1 natriuretic peptide (ANP) is elevated but plasma renin activity (PRA) and arginine vasopressin (AVP) are normal. Hormonal measurements have not been made acutely after MI because of the confounding effects of surgical stress. In many models, hormonal changes are maximal early in the development of heart failure and return toward normal in established heart failure. We have used coronary snares to produce coronary occlusion at a time that is remote from thoracotomy. A coronary snare was implanted in Wistar rats (n=33) under halothane anaesthesia. A femoral artery catheter was placed to measure arterial pressure (AP) and heart rate (HR). At least 2 weeks after thoracotomy animals were connected to a pressure transducer and the snare was tightened in 28 rats. Another 5 rats were treated similarly except that the snare was not tightened. AP and HR were recorded continuously After 60 minutes rats were decapitated and blood was collected for radioimmonoassay of AVP, PRA and ANP. Results were grouped by infarct size; control, ~30% - small MI, >30% - large MI. AP showed a response characterized by a profound hypotension that lasted for 15 - 20 minutes and then rapidly resolved and returned to control levels. The fall in blood pressure greater after large than small MI

ANP @g/ml) PRA(ngAl/ml/hr) AVP (pg/ml) Infarct size (%)

COlltrOl (n=5) 224 j: 23 0.95 f 0.41 9.5 i 4.8

Small MI (n=17) 500 + 86 1.59 i- 0.28 4.2 k 1.2 25 +l

Large MI (II=111 1010 * 161 13.4 i- 3.0 532 t 218 37 +1

ANP (F2,s0= 16.1, PcO.OOl), PRA (F230= 14.3, P
EFFECTS OF ACIDOSIS ON KV4.3 CURRENT STABLY EXPRESSED IN CHINESE HAMSTER OVARY CELLS: AN EXPLANATION FOR ITS MODULATION IN ISCHAEMIA S.Sinearayar*. H. Tie. 1. Bursill, K. Wvse. A. Bat&in. W. Wu. S. Breit. T. Camobell. Department of Medicine, Centre for Immunology and The Victor Chang Cardiac Research Institute, St. Vincent’s Hospital, Sydney Myocardial ischaemia produces both intra and extracellular acidosis. The transient outward current (ho,), one of the major cardiac potassium repolarisation channels is modulated by acidosis and has been implicated in the genesis of ischaemic arrhythmias. Previous published data has examined the effect of acidosis on Ito in rat and human ventricular myocytes, and on Kv1.4 currents. To our knowledge the effects of acidosis on Kv4.3 currents, the major component of Ito in the human ventricle has not been published. We have conducted a detailed analysis of the effect of acidosis on Kv4.3 currents Methods: Kv4.3 subunits were stably transfected in Chinese Hamster Ovary cells (CHOKI). Standard whole cell patch clamp techniques were used to measure changes in the current elicited after changing the HEPES buffered bath solution from a pH of 7.4 to a pH of 6.0. Results: Acidosis produced a significant depolarising shift in the voltage dependence of activation (V,,, = -20.6i3.9 mV at pH 7.4 and -6.6e2.7 mV at pH 6.0 [n=6, P=O.O04]). The voltage dependence of steady state inactivation was also significantly shifted to more depolarised potentials (V,,,= -48.5e1.3 mV at pH 7.4 to -38.6*1.7 mV at pH 6.0 [n=7, P
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DOPPLER TISSUE IMAGING OF THE MITRAL ANNULUS TO EVALUATE MYOCARDIAL ISCHAEMIA L Thorn a&, A Thiar+alingaml. K Levettl, N B Schillerz and D L Rossl, 2UCSF, San Francisco USA, Westmead Hospital, Sydney Australia. Doppler Tissue Imaging (DTI) measures longitudinal myocardial velocity and has been shown to detect myocardial ischaemia. We hyphotesised that mitral annular motion using DTI could identify and differentiate between LV ischaemia and infarction induced at a remote site. In an open chested sheep model (n=5), ischaemia was induced by percutaneous balloon angioplasty of the mid LAD with the balloon inflated for three 5 minute periods (no wall motion abnormality noted on 2D echo). After return of ECG to baseline, the balloon was reinflated and maintained for a total duration of 2 hours to produce infarction (wall motion abnormality present). Mitral annular peak systolic velocity (S), early diastolic velocity (E’) late diastolic atria1 contraction velocity (A’) were measured in the apical 4 chamber view. The mitral annular velocities were measured at baseline, following each period of ischaemia (x3) and at 60,90 and 120 mins to represent infarction. Results: The systolic velocity decreased with ischaemia and infarction and paired test showed significant differences between the magnitude of the S wave at baseline vs ischaemia (p=O.O04), baseline vs 60min infarction (p=O.O02), baseline vs 90min infarction (p=O.O024) and baseline vs 120min of infarction (p=O.O002). However no significant difference was noted between the ischaemic episodes vs those of infarction. No significant differences were noted in the E’ and A’ velocities at baseline, during ischaemia and infarction. Conclusion: Mitral annular peak systolic velocity (S) measured using DTI is decreased with both ischaemia and infarction and may be used to identify ischaemia at a remote site. However while a trend was shown of decreased S velocity with infarction vs ischaemia, in our current model mitral annular systolic velocity decrease could not differentiate between the two conditions.

DOES CONTINUOUS ST SEGMENT PATIENTS THAT FAIL THROMBOLYTIC Kucia. T.M. Brieus. C I Zeitz. Cardiology Health Service, University of Adelaide, SA.

MONITORING IDENTIFY THERAPY? K.I. Mishra’. A.M. Unit, North Western Adelaide

The optimal management of acute myocardial infarction involves restoration of patency of the infarct related artery. Many studies have used coronary angiography at 90 minutes to determine rates of such patency. An alternative methodology Involves continuous ST segment monitoring (STM). This has advantages in that it is non-invasive and is likely to represent the actual time of reperfosion. However, it is not yet established whether STM can give an earlier indication of patients who fail to reperfnse the infarct related artery following standard thrombolytic therapy We have investigated 50 consecutive cases of acute myocardial infarction presenting during 2000. All patients met GUSTO criteria for thtombolysis and had STM performed from arrival in coronary care and continuing for 24 hours. The clinical data is displayed in the table below. The time from initiation of thrombolysis until reperfosion (TR) was taken as the time (minutes) for the ST segment in the maximally displaced lead to fall by >50%, with this fall being sustained. The time of peak (maximal) ST elevation (PST) was also recorded. Of the 50 patients studied, 41 had evidence of reperfosion by 90 minutes post initiation of thrombolysis. Of the remaining 9 patients, 5 had rescue PTCA performed. We have demonstrated a significant correlation (r = 0.39, p = 0.006) between TR and the interval between time of PST and time of thrombolytic initiation. Of patients with PST at 30 minutes following initiation of thrombolysis, all had TR at >80 minutes. Conclusion: Continuous ST segment monitoring of patients during thrombolysis for acute myocardial infarction may allow earlier identification of patients who will fail to respond to this strategy. This may be relevant where alternative reperfosion strategies are available. Patients with acute myocardial infarction from l/1/00 to 31/12/00 Mean(SD)/Median Male = 39, Female = 11 Time to Presentation 99(86)/71.5 min Age 64(13) Door to needle 66(54)/50 min Inferior = 28, Anterior = 22 Peak CK 2400(1760)/2148 Streptokinase = 45, tPA = 5 TR 71(65)/52 min

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Heart,

TRENDS IN THE TREATMENT OF PATIENTS WITH RAISED TROPONIN-T LEVELS J.do.lM. li tt * Fal A. M Richards Christchurch School of Medicine, Christchurch, New Zealand The use of plasma troponin (TNT) has identified a group of patients with small myocardial infarction (MI) who have at the same medium term risks as patients with raised creatinine kinase (CK). These patients may also benefit from early invasive assessment and treatment. We have performed a retrospective case note audit and 1 yr follow-up of MI patients admitted to Christchurch Hospital from 1 Ott to 31 Dee in the years 1997,1998 and 1999. This analysis includes all patients admitted to the Cardiology Department with raised TNT levels greater than 0.10, but with a CK elevation of less than two times the upper limit of normal. There was an increase in in-hospital angiography (14% in 1997 to 33% in1999, 0.004) and angioplasty (3% to 19%, P=O.OOl) with no change in in-hospital mortality (4% to 2%, l’= 0.06) and a decrease in angiography in the year after discharge (table). Readmissons and one year survival were not decreased over the next yea*. n Median age y’s Inhospecho angio PTCA D/C on B-blocker D/C cmstatin Discharge alive D/Ctol yrangio PTCA Alive at 1 yr

1997 71 71 58% 14% 3% 75% 27% 96% 31% 23% 90%

1998 66 73 68% 20% 3% 64% 29% 98% 26% 14% 73%

1999 52 74 50% 33% 19% 71% 37% 98% 18% 33% 82%

There has been an increase in in-hospital angiography less intervention after discharge in patients presenting with no effect on long-term survival.

16% ‘p
2001; 10

INFARCJ.Falconer*. Christchurch

There is increasing evidence that coronary patients with ‘average’ cholesterol levels benefit from lipid lowering therapy. We performed a retrospective case note audit of all AMI patients admitted to Christchurch Hospital from 1 Ott to 31 Dee in each of 1997, 1998 and 1999. We have compared treatment in Cardiology and General Medicine (GM) departments. Overall, 30% of patients were treated in the General Medicine department, GM patients were older (median age 82 years vs 71 years), they had more comorbidities (previous infarction 47% vs 35%, P= 0.01) and there was a higher in-hospital mortality (18% vs 9%, P = < 0.05) Trends in the use of lipid lowering therapy are presented in the table. There has been an increase in the proportion of patients treated with lipid lowering therapy at discharge from Cardiology but not from GM, many GM patients do not have their lipids measured during hospital admission. In 1999, Cardiology patients were more likely to be discharged on aspirin (98% versus 79%, P= O.Ol), beta blockers (81% versus 50%, P= 0.01) and lipid modifying drugs (54 Cardiology

*

and Circulation

LIPID LOWERING THERAPY AFTER ACUTE MYOCARDIAL TION (AMI): TRENDS 1997-1999 IN CHRISTCHURCH J.l? __1 ar n B. R bb A. M School of Medicine, Christchurch, New Zealand

1997 1998 n 177 178 % on LM* 29% 35% lipid levels not tested (excluding

* **

Lung

* LM = Lipid In conclusion, older patient

13%

General Medicine

1999 1997 169 29 54% 3% those on LM drug) 9%

85%

1999 28 11%

81%

68%

modifying drug (statin or fibrate) at discharge secondary prevention measures are less frequently group treated by General Medicine.

used in the

and angioplasty, but with raised TNT levels

A MISMATCH BETWEEN PATIENTS’ EXPECTED AND ACTUAL SYMPTOMS OF A MYOCARDIAL INFARCTION RESULTS IN DELAY TO HOSPITAL PRESENTATION 1C Ellis* K Pe Morris. Depts. of Medicine and Behavioural Science, University of Auckland, Auckland. Audits of community myocardial infarction (MI) patients (pts) have consistently shown a long delay prior to hospital presentation. As a result, about 40% of MI pts die in the community, before accessing medical help. Previous studies have been unable to show consistent clinical and demographic factors related to delay, which anyway may be hard to address in order that the time delay might be shortened. We hypothesised that a mismatch between a pts prior perception of the symptoms of a MI and their actual symptoms experienced during a MI, would correlate with delay to hospital presentation, whereas pts who could recognise the symptoms of a MI would present sooner. During their coronary care unit stay, 47 MI pts completed an assessment of their symptom experience and behaviour before arriving at hospital. Clinical features, including delay were obtained from the pt and the hospital records. No clinical or socio-demographic factors were associated with pre-hospital delay. However, many pts showed a considerable discrepancy between expected and experienced symptoms and this was strongly associated with delay (r=0.45, p=O.OOZ). Delay was also positively related to not having a family member present during symptom onset (t[45]=2.23, p=O.O3), not talking to someone about symptoms (t(45]=2.07, p=O.O4), engaging in resting or taking medication prior to seeking help (t[45] =2.07, p=O.O5) and not calling an ambulance (t[45]=-2.10, p=O.O4). Multivariate analysis showed that the mismatch between expected and experienced symptoms was the most important factor in predicting delay. Conclusion: This study highlights the importance of symptom interpretation delay interval and suggests that in determinin g the length of the pre-hospital community interventions aimed at widening the range of symptoms perceived as associated with MI may be useful in reducing delay times.

GM)

1998 42 7%

SPINAL CORD HAEMORRHAGE COMPLICATING TREATMENT WITH STREPTOKINASE. JF England*, CM Sue, L Davis, M Rose, DS Crimmins and DH Curran Westmead Hosptial, Blue Mountains Hospital, Central Coast Neurosciences Study Group, Gosford and Shoalhaven Hospital, Nowra NSW who developed spinal cord We report three patients haemorrhage after the administration of intravenous streptokinase (SK) for suspected myocardial infarction. They developed back pain and signs of an acute spinal cord lesion. MRI of the spine showed that one patient had an intramedullary haemorrhage and the other two had late extradural haematoma with no underlying vascular All still have congenital abnormalities in all cases. residual neurological deficits. Awareness of this complication could improve morbidity as early surgery neurological recovery. In particular is crucial for chest pain radiating into the back should not only give rise to the suspicion of an acute aortic dissection but also raise the possibility of spinal haemorrhage. 55 year old hypertensive woman with regular Patient I.: neck manipulations was given SK, Heparin, aspirin and Left hand clumsiness occurred 18 hrs GTN infusion. later. Despite decompressive surgery for extradural haematoma on left side from C5 to T2 she is wheelchair bound 4 years later. Patient 2: 69 year old man with AF developed right leg weakness ten'minutes after SK and he was unable io move both legs with T6 sensory level after one hour. MRI T2-T4 and CT showed intramedullary haemorrhage at showed kidney and intramesenteric haemorrhage. Patient 3: 45 year old male 20 hours after SK and low dose Heparin developed upper chest and neck pain. Decompressive laminectomy for large C2-C5 extradural haematoma was performed but he remains a C3 incomplete quadripleyrc.

Heart,

Lung

and Circulation

2001; 10

CLINICAL SIGNIFICANCE OF INTERNATIONAL NORMALISED RATIO (INR) VARIABILITY WITH THE USE OF DIFFERENT THROMBOPLASTINS I.E. Brav*. E. M&n. T.E. Gan. R.E. Peverill. Centre for Heart and Chest Research, Department of Medicine, Monash University and Monash Medical Centre and Haematology Department, Monash Medical Centre, Clayton, Victoria. Commercially available thromboplastin reagents used for the determination of the prothrombin time vary in their response to coagulation factor depletion and each is assigned a value of the International Sensitivity Index (ISI) which is used for calculation of the INR. The INR/ISI system was designed to correct for differences between thromboplastins and coagulometers but it is now clear that complete normalisation cannot be achieved. The aim of this study was to investigate the variability of INR levels with some thromboplastins in common use and to determine the clinical significance of such variability. METHODS: We compared INR values using three thromboplastins, Innovin (I), Thromborel S (T), and RecombiPlasTii (R), in 65 patients with mechanical prosthetic valves. To control for differences due to coagulometers, all assays were performed on an ‘11 Futura’ instrument. The IS1 of each thromboplastin was calculated manually using calibration plasmas. INRs were divided into three ranges <2.5,2.5-3.5, and >3.5, with a difference between INRs defined as ‘clinically significant’ if the INRs fell into different ranges. RESULTS: Comparing I and T, there was a large difference in mean INR (3.5 vs 2.8, p
PLATELET FORMATION FROM MEGAKARYOCYTES IS INDUCED BY NITRIC OXIDE S.R. Willouhbyd*. E.M. Battine1lid.T.L.~. C.R. Valeril and 1. Loscalz~ Whitaker Cardiovascular Institute and Evans Department of Medicine”, Naval Blood Research Laboratory’ , Boston University School of Medicine and De artment of Animal and Nutritional Sciences, University of New Hampshire tp , USA. Platelets are formed from megakaryocytes and factors that mature megakaryocytes, such as thrombopoietin (TPO), increase platelet numbers in viva and in vitro. However, the molecular determinants of platelet formation remain poorly understood. Morphological changes in megakaryocytes associated with platelet formation and removal of senescent megakaryocytes are suggestive of an apoptotic process. Recently, we have shown that nitric oxide (NO) can induce apoptosis in the megakaryocytoid cell lines Meg-01 and Hel. To determine if there is an association between NO-induced apoptosis and platelet formation, we exposed Meg-01 cells to the nitric oxide donor Snitrosoglutathione (GSNO) in the presence and absence of TPO pretreatment and utilized flow cytometry to assess formation of glycoprotein IIIa-positive platelet-sized particles (PSI’). Meg-01 cells untreated or treated with TPO (100 rig/ml) for 72 hr produced few platelets (~3% of Meg-01 mass), while treatment with GSNO (100 ,uM) for 2 hr produced a significant percentage of PSI’ (22.4% of Meg-01 mass); when combined with TPO pre-treatment, GSNO led to a marked increase in PSI’ formation (48.32% of Meg-01 mass). Scanning electron microscopy (SEM) of these groups showed that cells treated with TPO and GSNO contained more megakaryocytes in the process of forming PSI’, while transmission electron microscopy (TEM) confirmed the ultrastructural features of platelets formed from megakaryocytes. PSI’ have functional platelet characteristics as the addition of calcium, fibrinogen, and thrombin receptor-activating peptide led to their aggregation. In addition, PSI’ express the active, fibrinogen-binding conformation of glycoprotein IIb/IIIa. Meg-01 cells grown in co-culture with fibroblasts that were stimulated to express iNOS and produce NO also revealed PSI’ formation, which could be increased by pretreatment with IL-11, serotonin, and TPO. In the absence of TPO pretreatment, the megakarycoyte population was positive for the apoptotic markers annexin-V and propidium iodide. Furthermore, gel shift assays demonstrated that treatment of Meg-01 cells with NO modulates the activity of the transcription factor NF-E2, which is known to be important for platelet formation. These results demonstrate that platelet formation from megakaryocytes by NO depends on TPO pre-treatment: in the absence of TPO treatment NO induces megakaryocyte apoptosis, in the presence of TPO pretreatment, NO induces platelet formation. We conclude that NO has bifunctional effects that govern the fate of megakaryocytes and the production of platelets.

49th Annual

Scientific

Meeting

of CSANZ

A89

MARFAN SYNDROME ANEURYSM AND ABDOMINAL AORTIC ANEURYSM PROMOTED BY DIFFERENT CELLULAR COMPONENTS. MI. Nataatmadia’. M Napatar. T. Watanabe*. S.P. Le Brocquei. K.M. Sum=‘, RI. Walker’. T.’ Dique’. M.1. West”. ‘Prince Charles Hospital, Royal Brisbane Hospital and Royal Children’s Hospital, Brisbane and *University of Tsukuba, Japan. The mechanisms underlying the development of aortic aneurysm are not understood. We have examined the role of inflammation and apoptosis in the pathophysiology of thoracic ascending aortic aneurysm due to Marfan syndrome (MS) and abdominal aortic aneurysm (AAA) using immunohistological techniques. Aneurysm in MS is due to a defect in the matrix protein fibrillin and develops especially in young adults. AAA occurs in the elderly, has a familial tendency and is often associated with atherosclerosis. Aneurysm tissue from 5 subjects with MS, 5 with AAA and tissue from 5 subjects with normal aortae were used for the study Immunohistological analyses of aortic tissue and cells cultured from aortic tissue were carried out using antibody markers for apoptosis (PARF ~85 fragment pAb (~85) and bcl-2), metalloproteinases (MMP) (MMP-2 and MMP-9) and MMP inhibitors (TIMP1 and TIME’-2). In MS there was an absence of inflammation and at the border of the areas of aortic wall degeneration VSMC were stained positively with ~85. Staining with bcl-2 was minimal. These findings indicate the presence of apoptosis. The cells also showed increased expression of MMP-9 indicating an association between expression of MMP-9 and apoptosis. In AAA there was increased expression of MMP-2 in areas of inflammation suggesting an interaction between MMP-2 and the process of inflammation. The study indicates that MMP-9 plays an important role in MS aneurysm possibly by inducing cell apoptosis. In AAA MMP-2 appears to regulate the proliferation and activation of inflammatory cells leading to increased protease activity and wall degeneration.

THE EFFECT OF LOWERING TUMOUR NECROSIS FACTOR-ALPHA ON VASCULAR ENDOTHELIAL FUNCTION IN NON-INSULINDEPENDENT DIABETES MELLITUS. W Bilsboroueh’. RR T&or. IG O’Driscoll. R.Weerasoo ‘va. L Dembo. K Stanton. Dl Green. Cardiovascular Division, Royal Perth Htspital, Perth WA, 6001. Tumour necrosis factor-alpha (TNF-a) is a potent pro-inflammatory cytokine and mediator of reactive oxygen species (ROS). Both inflammation and ROS are implicated in endothelial dysfunction and progression of atherosclerosis. Type II diabetes is associated with endothelial dysfunction and the serum concentration of TNF-a has been shown to be elevated when compared to controls. Strategies that reduce pro-inflammatory species and decrease oxidant stress may provide clinical benefit by impeding the progression of cardiovascular disease. We hypothesised that reducing serum levels of TNF-c(, using oxpentifylline, would improve endothelial function in resistance and conduit arteries. METHODS: 3 female and 8 male subjects (age 59 + 1.86 years; mean + s.e.) with type II diabetes (disease duration 74 _+12.63 months) undertook a randomised, crossover study of oxpentifylline (Trenta1400) (8-weeks) and placebo (&weeks). Following each S-week period, endothelial-dependent and independent vasorelaxation in resistance arteries was assessed via bilateral forearm venous occlusion plethysmography during intra-bra&al infusions of acetylcholine (ACh; 10, 20, 4Oug/min) and nitroprusside (SNP; 2, 4, 8ug/min). High resolution ultrasound of the brachial artery in response to an ischaemic stimulus was used to determine endothelium-dependent conduit vessel flow mediated dilatation (FMD) and endothelium-independent function was assessed via sublingual administration of glyceryl trinitrate (GTN) (4OOug). Serum concentrations of TNF-c( were also determined following each S-week period, using chemiluminescent enzyme immunometric assay. Student’s paired t-tests were used to determine differences between treatment groups, with ANOVA used to determine any interaction between treatment and infused drug doses. RESULTS: In response to oxpentifylline, serum concentrations of TNF-a decreased from 3.27 i 0.51 pg/mL (mean 2 se) to 2.12 * 0.54 (P=O.O03). Forearm blood flow ratio responses, presented as percentage changes from baseline, at each dose of Ach (P=O.4) and SNP (P=O.9) did not differ between treatment groups. There were no differences between treatment groups when comparing changes in brachial artery diameters during FMD (P=O.3) or GTN administration (P=O.9). CONCLUSION: TNF-a is a known stimulant of superoxide anion production in the vessel wall, a substance that impairs endothelial function. Oxpentifylline down-regulates TNF-a production. However, the results of the present study demonstrate that administration of oxpentifylline at a dose of 400 mg tds for 8 weeks, does not improve vascular function in either conduit or resistance vessels in type II diabetes.

A90

49th Annual

Scientific

Meeting

of CSANZ

Heart,

INCORPORATION OF N-3 POLYUNSATURATED FATTY ACIDS INTO ATRIAL MYOCARDIUM OF CORONARY BYPASS PATIENTS FOLLOWING SUPPLEMENTATION WITH A FISH OIL CONCENTRATE. R.I. Blake’. l.Liig*-J.W. Leitch2, M.L. Garg’ ‘Discipline of Nutrition & Dietetics, Faculty of Medicine & Health Sciences, University of Newcastle. Tardiology Department, John Hunter Hospital, New Lambton Heights. While it has been well established that a diet high in long chain n-3 polyunsaturated fatty acids (n-3 I’UFA) is beneficial in reducing the risk of cardiovascular disease, the mechanism via which this risk is reduced is not clear. It has been hypothesised that incorporation of n-3 PUFA into myocardial cell membranes may influence the electrophysiological properties of the heart, such as fibrillation threshold, and the contractile responses of coronary arteries. This experiment was carried out to determine the extent of incorporation of n-3 PUFA into human myocardium following dietary supplementation with a fish oil concentrate high in eicosapentaenoic and docosahexaenoic acids. Volunteers who were preparing for coronary bypass surgery were randomised either to the treatment group (n=8), receiving 6 g/day of fish oil concentrate (4.4g of n-3 PUFA) or the placebo group (n=9), receiving 6 g/day of olive oil for a minimum period of 6 weeks. Blood samples were collected prior to commencement of treatment, and pre-operatively before bypass surgery. Atria1 biopsies were obtained during surgery. There was no significant difference in plasma fatty acid profiles between the groups at baseline. Following supplementation, the treatment group had significantly higher plasma levels of C20:5n-3, C22:5n-3 and C22:6n-3 than the placebo group. Analysis of the atria1 samples revealed a significant increase in the proportion of C20:5n-3 incorporated into myocardial cells. Fatty Acid Atrium (% total lipid) Placebo Fish oil

C20:5n-3’

c22:5n-3’

C22:6n-3’

0.37 ct 0.04 1.33 +_0.20’

1.14 + 0.13 0.93 * 0.17

2.88 * 0.40 3.39 + 0.68

hean f SEM * Significantly different (p< 0.05) from the placebo group.

This study demonstrates for the first time that short term supplementation with fish oil concentrates can result in significant incorporation of QO:5n-3 into human myocardium. However, myocardium may be resistant to C22:5n3 and C22:6n-3 uptake from plasma. ENDOTHELIUM DEPENDENT AND INDEPENDENT VASCULAR REACTIVITY IN OBSTRUCTIVE SLEEP APNEA J.L.Lattimore*. LWilcox, MRSkilton. Department of Cardiology, Royal Prince Alfred Hospital, Sydney. Obstructive sleep apnea (OSA) is associated with an increased risk of cardiovascular and cerebrovascular events. Whether this association is independent of concomitant risk factors, such as obesity and hypertension, remains unknown. GSA is a condition characterised by repetitive hypoxia, arousal and surges of sympathetic activity. The effects of OSA per se on endothelial function in particular, and vascular reactivity in general (key determinants of atherosclerotic risk), however, are not well characterised. Eleven subjects with untreated OSA (Apnea Hypopnea index >lO) had large and small vessel forearm vascular reactivity studies. Large vessel (brachial artery) size was measured by ultrasound, at rest and in response to endothelium dependant (flow mediated dilation (FMD)) and endothelium independent (sublingual GTN) vasodilator stimuli. Eleven controls were carefully matched for age (56k8.7 YS 55t9.7), body mass index (29.4+3.0 vs 30i2.7) and cardiovascular risk factors. Metabolic vasodilation was assessed by the response to reactive hyperaemia (peak and area-under-the-curve measurements) using venous occlusion plethysmography in 5 subjects and 5 controls. Finally, detailed microvascular responses were assessed in 6 OSA subjects by intra-arterial infusions of acetylcholine, nitroprusside, L-NMMA and L-Arginine. Large vessel function was similar in OSA and control subjects (FMD 3.5tO.8 vs 4.5+0.7%, GTN 15.522 vs 13.3+1.8, p>O.lO). Baseline forearm flow (2.4-e0.3 vs 1.7+0.2 ml/min/lOOmg, p=O.l) and metabolic vasodilator responses (peak and area under the curve) were also similar between OSA and control groups. Acetycholine produced dose-related flow increase in OSA subjects, but this was not attenuated by co-administration of L-NMMA; no control subjects have yet been studied [email protected] In this study, OSA per se was not associated with impaired reactivity in large or small vessels, suggesting that co-existing risk factors play a more important pathogenic role in these subjects, rather than repetitive hypoxic episodes.

Lung

and Circulation

2001; 10

GLYCERYL TRINITRATE DECREASES MONOCYTE ADHESION TO STIMULATED ENDOTHELIAL CELLS, A POTENTIALLY ANTIATHEROGENIC EFFECT. S. Nakhla*, A.K. Death, W. lessuu, D.S. Celermaier. Royal Prince Alfred Hospital and Heart Research Institute, Sydney, Australia. Glyceryl trinitrate (GTN) is a commonly ischaemic heart disease. As it may release the key early atherogenic event of monocyte investigated the effect of GTN on vascular cells.

used agent in the treatment of nitric oxide, which can influence adhesion to endothelial cells, we adhesion, using primary human

Human umbilical vein endothelial cells (ECs) were grown to confluence (passage 2-4) and human monocytes were obtained by eluiriation. Adhesion was assessed by automated cell counting (Bayer Technycon H2) and endothelial cell adhesion molecule expression (E-&a&in, ICAMand VCAM-1) assayed by ELISA. Experimental conditions included control; GTN 200-2OOOuM (the latter being an approximate pharmacological concentration during angina treatment); glycerol 200-2oOOuM, SIN-1 and L-A&nine (nitric oxide donor and substrate respectively). Adhesion and ELISA were measured in unstimulated ECs and in ECs after IL-lb or TNFa stimulation. Each experiment was repeated -13 times and average results presented. GTN 2ooOuM decreased monocyte to EC adhesion in cells stimulated by IL-lb or by TNFa (to 85210% control, p< 0.05). This was not observed at lower GTN concentrations or with glycerol, SIN-l or L-arginine, nor in the unstimulated endothelial cells. High dose GTN, however, did not significantly decrease EC expression of ELAM, ICAMor VCAM-1 (p> 0.10 in each case). Similarly, other nitric oxide donors did not change CAM levels significantly. Therefore GTN, in therapeutically relevant concentrations, decreases monocyte endothelial cell adhesion, possibly via down regulation of adhesion-related integrins on the monocyte cell surface. This may correspond to a possible anti-atherogenic effect.

REPETITIVE HYPOXIA DOES NOT INCREASE ADHESION MOLECULE EXPRESSION OR HUMAN MONOCYTE ADHESION TO ENDOTHELIAL CELLS 1.L.L L e* I Wil ox w. The Heart Research Institute and Department of Cardiology, Royal Prince Alfred Hospital, Sydney. Obstructive Sleep Apnea (OSA) is associated with cardiovascular disease. Whether this association is directly causal, or a result of confounding factors such as obesity and hypertension, remains to be established. OSA is characterised by repetitive episodes of hypoxia. We therefore investigated the effects of repetitive and sustained hypoxia on monocyte-endothelial cell adhesion, a key early event in atherogenesis. Human umbilical vein endothelial cells (HUVECs) were grown to confluence (passage 2-4) and exposed to 30 minute cycles of 5%/21% oxygen, constant 5% oxygen, or control gas (room air in a 5% CO2 incubator). A subset of HUVECs from each condition were incubated for a further 20 hours in normoxie,. The endotheiial cell adhesion molecules ELAM, ICAMand VCAM-1 were assessed by ELISA, with and without IL-lI3 stimulation. Human monocytes, separated from healthy donors by centrifugal elutriation, were added to HUVECs treated under the same conditions. Adhesion was assessed after one hour by automated cell counting (Bayer Technycon). All experiments were performed in triplicate. Cell viability was >90% in all experiments. Monocyte adhesion to HUVECs was unchanged by exposure to repetitive hypoxia (102%+1.8) or constant hypoxia(94%*2.5) compared to normoxic conditions (lOO%, p>O.O5). Similarly there was no change in adhesion after reincubation at normoxia for 20 hours (105%*6.3 and 89%s9.8). Consistent with this, there was no significant change in adhesion molecule expression with repetitive hypoxia (ELAM 101*9.8, ICAM 105k7.6, VCAM 107+4.0% of control values), or constant hypoxia (ELAM 1061t6.4, ICAM 112t3.6,VCAM 106+2.5%). Similar results were obtained in both the unstimulated and stimulated HUVEC experiments. Therefore neither repetitive nor sustained hypoxia induce adhesion molecule expression or monocyte adhesion to vascular endothelium, suggesting alternate mechanisms for OSA related cardiovascular disease.

Heart,

Lung

and Circulation

49th

2001; 10

IMPAIRED PRE- AND POST-PRANDIAL TION IN DIABETIC ADULTS. M.R. A.C. Clinical Biochemistry, Royal Prince Alfred

METABOLIC

VASODILATA-

Departments of Cardiology Hospital, Sydney.

and

We have recently shown that eating a fatty meal induces vasodilatation (of both resting and stimulated forearm flow) in healthy young adults, an effect possibly mediated by post-prandial changes in insulin levels. We therefore investigated pre- and post-prandial vascular reactivity in healthy and in diabetic subjects, hypothesising that an impaired meal-related vascular response might be an “in vivo” marker of insulin resistance. 32 volunteers were studied before and 3 hours after a high-fat meal (1030 kcal, 61g fat). Resting and post-ischaemic forearm blood flow were measured using venous occlusion strain-gauge plethysmography, to derive peak hyperaemic and “area under curve” (AUC) flows. We investigated 12 young controls (33-+7 years), 10 type II diabetic subjects (56+9 years) and 10 age matched older controls (55klO years). Regarding both pre- and post-prandial responses, peak and AUC flows were significantly lower in diabetic adults compared to both the old and young controls. For example, 3 hours after the meal, the increase in AUC compared to baseline flow was 276% (89-403) (geometric mean over time, 95% CI in parentheses) in young controls, 273% (199-375) in the older controls and 178% (137-230) in the diabetic subjects (p=O.O04, diabetics vs older controls). Peak hyperaemic values were 1064% (790-1434), 773% (509-1173) and 518% (377-712) respectively (p=O.OOl). Therefore pre- and post-prandial vasodilatation are impaired in diabetic subjects compared with controls. Given that such vasodilatation may be insulinrelated, loss of this response in diabetic adults may represent a manifestation of vascular insulin resistance. Analyses of these vascular changes and their relationship with lipid and insulin levels in these subjects before and after the fatty meal are currently ongoing.

SUSCEPTIBILITY OF LOW DENSITY LIPOPROTEIN (LDL) TO IONDEPENDENT OXIDATION AND EXTENT OF CORONARY ATHEROSCLEROSIS D.M. Colauhoun*. P.A. Kroon. P.M. Will, B.J. Hicks. M.Davidson. F.A. m, Core Research Group, Wesley Hospital and The University of Queensland, Brisbane, Australia

Oxidative modification of LDL appears to increase the atherogenicity of the lipoprotein and play a casual role in coronary atherosclerosis. Oxidation of LDL may occur to some extent in the vascular lumen, and susceptibility to oxidation may predict more extensive

coronary

atherosclerosis.

74 patients undergoing catheterization were enrolled: 57 M, 17 F, 66% stable angina, 51% smokers, diabetes 13%. Mean serum cholesterol

was 5.62 mM,

fasting

triglycerides

2.02 mM,

HDL-C

1.1

mM, fibrinogen 4.00 g/L, apo B I. I4 g/l, apo A-I 1.18 g/l, Lp(a) 0.42 mgldl. Coronary angiograms were scored visually according to number of vessels diseased (VN) and a global score of extent of disease (GS). LDL was isolated from plasma and exposed to copper ions to stimulate oxidation. Oxidation was assessed spectrophotometrically by changes in absorbance at 234 run as a function of time and the plot divided into lag, propagation and degradation phases (LP, PP, DP). Multivariate analysis revealed a borderline significant difference in susceptibility to oxidation between

patients

with no disease

(9) and those with

disease

(66).

In

the 66 patients with disease there was no relationship of LP, PP or DP with coronary disease, either NV or GS, GS correlated with stable angina, diabetes and fibrinogen (all P
Annual

Scientific

Meeting

A91

of CSANZ

COMPARISON OF ZD452.2 TO ATORVASTATIN IN THE TREATMENT OF PATIENTS WITH HETEROZYGOUS FAMILIAL HYPERCHOLESTEROLEMIA D.M.1, K.L. [email protected], E.Steins. ‘Core Research Group, Wesley Hospital, University of Queensland, Brisbane (for the Australian HeFH group); 2AstraZeneca, Cheshire, UK; “Metabolic and Atherosclerosis Research Centre, Cincinnati, Ohio, USA. Background: Heterozygous familial hypercholesterolemia (HeFH) is a common genetic disease leading to premature ischemic heart disease. ZD4522 (rosuvastatin) is a new statin with potent, dose-dependent LDL-C-lowering effects. The primary objective of this trial was to compare the efficacy of ZD4522 with that of atorvastatin in the reduction of LDL-C in patients with HeFH. Methods: A randomized, double blind, parallel-group, forced-titration, comparative trial conducted at 58 centers worldwide. Entry criteria included patients (218 years) with HeFH, mean fasting LDL-C concentrations b5.69 mmol/L but 12.93 mmol/L, and fasting triglycerides (TG) < (4.52 mmol/L. Following a 6-week dietary run-in period, there was a weighted randomization to once-daily treatment with ZD4522 (n=435) or atorvastati (n=187); initially 20 mg/d, and force-titrated at h-week intervals to 40 mg/d and then 80 mg/d (18 weeks on treatment in total). Results: Change from baseline (%) Drug

LDL-C

HDL-C

TC

TG

Ago B

Apo Al

-58'

+12'

-46'

-28ns

-50'

+6'

-50

+3

-42

-32

44

-2

(20/40/80 q/d) ZD 4522 (n1435) Atorvastatm (n=187)

Table 1. Summary of data at 18 weeks. * p
STATIN MYALGIA, NORMAL CK AND MITOCHONDRIAL CHANGES JF England*, A Vile*, P Stewart, M Halmagyi Blue Mountains Hospital, Royal Prince Alfred HoSpital Sydney NSW The aging process in muscle is linked to a decline in mitochondrial function and deletions in mitochondrial DNA in human heart and skeletal muscle. Late onset mitochondrial myopathy over 65 years has linked a clinical symptom complex with exaggerated age related abnormalities in mitochondrial function on muscle biopsy manifest via cytochrome C oxidase and geranylgeranylated proteins. During the LIPID Study we reported one active pravastatin trial patient withdrawal and other simvastatin patients with similar mitochondrial abnormalities at previous Cardiac Society Meetings. We have now analysed retrospectively the Blue Mountains trial population and linked the symptoms of myalgia with needle muscle biopsy findings and muscle mitochondrial chemistry. 13 patients out of 111 patients were biopsied, only 5 were withdrawn from the LIPID Study on the basis of symptoms and mitochondrial changes. When the code was broken 7 years later all 5 patients were on active pravastatin therapy. The influence of drug-drug interactions is more apparent after simvastatin mibefradil (Posicor) interactions. A 66 year old woman on simvastatin for 2 years started mibefradil and was hospitalised with profound muscle weakness and the CK rose progressively to 27,700 and three serial yearly muscle biopsy findings are presented. Cytochrome P450 drug metabolism and inhibition has to be considered with all statin and SSRI anti-depressant therapy. HmG Co A reductase inhibitor's metabolism is susceptible to inhibitors of hepatic cytochrome P450 isoform CYP3A. This opens a new spectrum for the assessment of such a vague clinical diagnosis as myalgla and polymyalgia rheumatica when contrasted with rhabdomyolsis and raised CK levels.

A92

49th Annual Scientific Meeting of CSANZ

Heart, Lung and Circulation 2001; 10

COMPARISON OF ZD4522 TO ATORVASTATIN IN THE TREATMENT OF PATIENTS WITH PRIMARY HYPERCHOLESTEROLEMIA mMa*.l M. Davidson.2 A. Raza.3 ‘Heart Health Institute Research Clinic, Calgary; Canada, ZChicago Center for Clinical Research, Illinois, USA; 3AstraZeneca, Wilmington, USA Background: Many patients still fail to achieve the National Cholesterol Education Guidelines (NCEP) LDL-C targets following initiation of therapy. ZD4522 (rosuvastatin) is a new, highly efficacious statin which achieved up to 65% LDL-C lowering in clinical trials. This trial compared ZD4522 with atorvastatin and placebo to evaluate lipid effects and achievement of NCEP LDLC goals. Methods: A randomized, double blind, placebo-controlled trial in 516 patients with primary hypercholesterolemia (LDL-C 2160 and ~250 mg/dL; TG gO0 mg/dL). Following a 6-week dietary run-m period, patients received ZD4522 5 or lOmg, atorvastatin 1Omg or placebo for 12 weeks. Results: Change from baseline (%) Treatment LDL-C HDL-C TC TG Apo B Apo Al Placebo (~132) (n=132) ZD4522 5mg (n=128) ZD4522 1Omg (n=129) Atowastatin 1Omg

0

+4

0

-1

c4

c3

-40’

+13*

-288

-17

-31’

+7*

-43-s

+12*

-30”

-19

-33”

+7*

-35

+8

-25

-19

-26

+3

*p<0.05,**p<0.001 “S atorvastatin. Conclusion: 5 and 1Omg ZD4522 is superior to IOmg atorvastatin in lowering LDL-C, TC and Apo B and in raising HDL-C and Apo AI levels. These findings, along with a potential advantage in getting more patients achieving NCEP goals, make ZD4522 a promising new medication for the treatment of dyslipidemias.

THE ABC-l RECEPTOR Is NOT ESSENTIAL FOR APOLIPOPROTEIN A-IINDUCED SECRETION OF APO E FROM FOAM CELL MACROPWGES M. Kockx”. D. Sullivan*. R. Dean’, W. Jessuo’ . and L. Kritluuides’~3.‘The Heart Research Imtihrte, ‘Dept. Biochemistry Royal Prince Alfred Hospital, and ‘Dept. Cardiology Concord Hospital, Sydney, Australia. Local, arterial secretion of apoE by macrophages is anti-atherogenic, and apolipoprotein (apo) A-I, the main protein component of high density lipoprotein (HDL) stimulates this secretion. Recently, the ATP-binding cassette transporter protein (ABC-l) was shown to mediate cellular cholesterol efflux to apoA-I, and dysfunctional ABC-I was identified as the genetic defect in Tangier Disease (TD). Whether apoA-I-induced apoE secretion occurs via ABC-l is unknown. Monocytes isolated from healthy donors (C-HMDM) or from a subject with clinical and genetically continned TD (TD-HMDM) were differentiated and cholesterol enriched before incubating with apoA-I. Cholesterol eftlux was measured by scintillation counting and HPLC, and apoE secretion by Western Blotting. C-HMDM released 7.5 f 2.0% (mesnfSD, n=3) of cell cholesterol to control medium, and 17.2 f 3.6% to apoA-I (p5fold from C-HMDM and from TD-HMDM. Moreover, although ABC-I inhibitor Gly did inhibit constitutive apoE secretion from C-HMDM to 0.2-fold of control (pcO.OOl), apoA-I still stimulated apoE secretion 3.7-fold (p=O.O2) in HMDM exposed to Gly. Our results support a role for ABC-1 protein in apoA-I-stimulated cholesterol efflux from HMDM and possibly in constitutive apoE secretion, but indicate that ABC-1 is not essential for apoA-I-induced apoE secretion. These studies indicate that apoA-I induces important physiological responses in foam cells by interactions other than via the ABC-I receptor.

A NOVEL HUMAN SERUM PHOSPHOLIPASE A2 ASSOCIATED WITH HIGH-DENSITY LIPOPROTEINS N. Petrovic. P Laneton*. C. Grove, N. Misso & P.1. Thomoson Department of Medicine, University of Western Australia, Perth, Australia Aims: Atherosclerosis is associated with both inflammation and the formation of oxidised low density lipoproteins (oxLDL). The inflammatory enzyme, phospholipase A2 (PLA2) can inhibit the protective effect of HDL on the in vitro and in viva oxidation of LDL. PLA2 is usually assayed with expensive radioactive or chromogenic substrates unsuitable for performing large numbers of assays. We sought to develop a novel assay for PLA2 and to determine the relationship of human serum PLA2 activity to lipid levels. Methods: We have developed and validated a new microplate assay for human serum PLA2 using the chromogenic substrate 4-nitro-3-octanoyloxybenzoic acid. This assay has been applied to the measurement of PLA2 activity in fasting serum from 30 healthy volunteers. Results: Using this substrate, PLA2 assay results were similar to those obtained with the previously characterized PLA2 chromogenic phospolipid substrate 1,2-bis-heptanoylthio-glycerophosphocholine. However, the assay described here appears to be more sensitive. The assay is reproducible and it is suitable for the analysis of large numbers of samples in a clinical setting. The PLA2 activity characterised is not due to platelet-activating factor acetylhydrolase or to low molecular weight His-Asp PLA2, and may represent a new PLA2 type. The mean PLA2 activity was 10.4 r 1.6 umole h-lml-1. In human serum, PLA2 activity is predominantly associated with high-density lipoproteins (94.0%), and is strongly correlated with total cholesterol concentration (p
ARE THE SMALL VESSEL (Z.OMM-2.5MM) COATED BIODIVYSIOTM STENTS USEFUL ADJUNCTS TO EXISTING TREATMENT FOR CORONARY DISEASE? CT Liew*. H Kachwalla. C Fernandes. S Newuort A Wonv. CP luergens. Al’ Hopkins. ST Lo. HC Lowe. Cardiac Catheterisation Laboratory, Cardiology Department, Liverpool Hospital, Sydney, NSW, Australia Background. Stenting in small vessels 52.5mm has been associated with increased acute and longer term morbidity The BiodivYsion” SV (BYS) stent is a novel phosphorylcholine-coated stem designed for small vessels, which may lower the incidence of subacute stem thrombosis and improve long term outcome of percutaneous coronary interventions (ICI). The stem is available on 2.0 and 2.5mm balloons and has the lowest crossing profile and stem strut thickness of currently available stems. It is also a local drug delivery platform. We therefore analysed our initial experience using these stems in small vessels. Methods. All patients undergoing PC1 using only the BYS 2.0 and 2.5mm stems from Ol/Ol/OO to 31/12/00 were retrospectively analysed by computer database and case note review. Clinical follow up was performed at 6 months. Results. Thirty-two lesions were treated in 30 patients. Nineteen patients were semi-urgent while 11 had elective ICI. There were 6 type A, 7 type Bl, 12 type 82 and 7 type C lesions. Thirty-nine stems were successfully deployed. Fifteen 2.Omr-n and 24 x 2.5mm stems were used. Six patients had multiple stems implanted. Two had a (stent-through-stem) second stem used for distal stem edge dissection or distal lesion and 4 had multiple stems for diffuse lesions. Patients received standard anti-platelet therapy post-procedure and abciximab was used in 6 patients (20%). The procedural success was 31/32(97%). One procedural failure in a patient undergoing emergency PC1 was successfully treated by coronary bypass grafting. Mean vessel stented length was 16.6t7.Omm. There was no incidence of subacute stem thrombosis. Angina recurred in 4 patients and all were angiographically confirmed as in-stem resterroses. Two were medically treated and two had repeat balloon angioplasty. Conclusions. Small vessel stenting using the BYS 2.0 and 2.5mm stems is associated with a high procedural success rate and promising long term clmical results. For selected cases, these stems are useful adjuncts to existing treatments for coronary artery disease.

Heart,

Lung

and Circulation

2001;

49th Annual

10

ASSESSMENT OF RECIPIENT CORONARY FLOW ARTERY BYPASS GRAFT WITH FRACTIONAL KSPa rk* .K. o .H. L Department, Inha University Hospital, lnchon, Korea

AFTER CORONARY FLOW RESERVE. Cardiology

Coronary angiography (CAG) and intravascular ultrasound have been used to assess the result after CABG, but they had several limitations to meet the purpose. The purpose of this study is to evaluate the recipient coronary flow after CABG with fractional flow reserve (FFR) in comparison with CAG and to investigate the major determinants of the recipient coronary flow. Of the 27 patients, 39 bypass grafts lesions examined except bypass graft with complete obstruction. In all of 39 lesions were shown good distal flow (TIMl3) without significant narrowing by CAG. However, FFR did not always show the agreement with CAG (36 lesions with FFR>0.75, 3 lesions with FFRc0.75). FFR is higher in saphenous vein graft group (SV)(0.90r0.06) than in the internal mammary arterial graft group (IMA)(0.81+0.08) (pi.05). FFR showed no significant correlation with ratio between the recipient and conduit vessel size (r=0.13, p>.O5 in IMA and rz0.08, p>.O5 in SV). In conclusion, postoperative evaluation with FFR is helpful for the assessment of CABG status even in patients with angiographically good distal flow.

Scientific

Meeting

of CSANZ

A93

MONTE CARLO DOSE PROFILES FROM TANDEM POSITIONING WITH A STRONTIUM-90 SEED TRAIN IN CORONARY BRACHYTHERAPY W. Schumer”, S. Wallacel. M. Horrigan Austin & Repatriation Medical Centre, Department of Cardiology, Melbourne, Victoria, Australia 1W.P. Holman Clinic, Royal Hobart Hospital, Tasmania, Australia Manual tandem positioning of a single fixed length Sr-90 seed tram may be required to fully irradiate long lesions in coronary arteries to prevent geographic miss and the subsequent “edge effect”. In clinical practice a manual pull back technique is performed by visual approximation and a single seed train can be used to irradiate proximal and distal segments of one target lesion. In this study we aim to quantify the degree of inhomogeniety which will occur in the junction region when tandem positioning is used. Monte Carlo data, generated by theoretical mathematical modeling was used to illustrate dose profiles 1.5,2.0 and 2.5 mm away from, a tandem positioned 30mm Sr-90 seed train. The dosimetry from abutting, overlapping and spaced seed trains was illustrated. A homogeneous dose distribution is achieved by precise abutting of seed train positions. Overlapping train positions by 2.5 mm results in a maximum of 160% of the prescribed dose at a distance of 2.0 mm, however, up to 300% of the prescribed dose occurs at 1.5 mm from the source axis. When a gap of 2.5mm occurs between the seed train positions a minimum of 38% of the prescribed dose occurs at the treatment distance. These results underscore the need for meticulous dose delivery to avoid regions of injury combined with high and low doses which is thought to be causal in restenosis. ECG gated imaging, careful attention to anatomical landmarks and superimposition of angiograms may be helpful in achieving homogeneous dose distributions when tandem positioning is used.

LONG-TERM OUTCOMES IN DIABETIC PATIENTS FOLLOWING INTRACORONARY RADIATION FOR IN-STENT RESTENOSIS L !A r A E. ni* - Ki R Waksman. Washington Hospital Center, Cardiovascular Research Institute, Washington DC.

TRANSOESOPHAGEAL TISSUE DOPPLER VELOCITY, STRAIN AND STRAIN RATE IMAGING DURING OFF-PUMP CORONARY ARTERY BYPASS SURGERY L.A. Simmons’. A. Rubinstein. G.R. Sutherland. J D’hooee. I’. Claus, B. Bijnens. l? Sereeant. l? Wouters. Cardiology, Anaesthesia and Cardiac Surgery, UZ Gasthuisberg, Leuven, Belgium.

Background: Diabetic patients are known to have excessive neointimal hyperplasia and a high recurrence rate of in-stent restenosis (ISR) after conventional percutaneous intervention. Intracoronary radiation therapy (IRT) has been shown to reduce the recurrence rate of ISR. Methods: The impact of IRT on the 6-month clinical and angiographic outcomes was assessed in 252 diabetic and 371 non-diabetics who were enrolled in the WRIST (Washington Radiation for In-Stent restenosis Trial) protocols using b and g emitters. Results: Clinical and angiographic characteristics and 6-month outcomes are shown (Table, *p < 0.05).

Aim: This study investigated whether transoesophageal Doppler myocardial imaging facilitates detection of myocardial ischaemia during off-pump coronary artery bypass surgery (OPCAB). Methods: Transoesophageal echocardiography was performed in 14 patients (age 67 + 5 years, 9 men) during elective off-pump coronary bypass (internal mammary to left anterior descending artery (LAD)). Anastomoses were performed using intraluminal shunts to limit the duration of ischaemia to less than 3 minutes. ‘lissue Doppler data were acquired prior to LAD ischaemia (n=14), during surgery when surgical positioning of the heart permitted transoesophageal imaging (during ischaemia (n=4), following reperfusion at 5 min (n=6), 30 min (n=9), 60 mm (n=8) and 90-120 min (n=5)) and finally during infusion of dobutamine (Dob) 5kg/kg/min (n=lO). Regional velocity (V) analysis was performed for the transgastric anterior wall to assess radial myocardial function and strain (E) and strain rate (SR) were derived. Results: During LAD occlusion, systolic E and SR decreased (baseline E: 33 + 15%, ischaemia E: 12 + 20%, p NS; baseline SR: 1.89 + 0.45/s, ischaemia SR: 1.70 r 0.53/s, p NS) with no change in V. Following 5 minutes of reperfusion (Q5), systolic V, E and SR values returned to baseline levels (baseline V 3.5 + l.lcm/s, Q5 V: 4.5 f l.Ocm/s, p NS; Q5 E: 36 f 9%, p NS vs baseline; Q5 SR: 2.18 * 0.68/s, p NS vs baseline) and remained constant during the remainder of the operation. During Dob, systolic V and SR increased (Dob V: 5.7 + 2.0cm/s, p=O.O25 vs baseline, Dob SR: 2.73 i 0.78/s, p=O.O23 vs baseline). Conclusions: Transoesophageal Doppler myocardial imaging is feasible during off-pump coronary artery bypass surgery and dobutamine infusion. Recovery from transient LAD occlusion normally occurs within 5 minutes of reperfusion. Doppler myocardial indices may prove useful for monitoring ischaemia in the operating theatre.

DIABETICS

tN=252)

NON-DIABETICS

Age, y’s

62+10

Males, % Hypertension, % Lesion Length, mm Reference vessel diameter, mm Final MLD, mm 6 monthsfollow-up Late Loss, mm Binary Restenosis (> 50%), % Death, % Myocardial Infarction, %

60 82 24 t 11 2.5 + 0.6 1.8 f 0.4

62~12 71’ 66’ 24 + 13 2.7 k 0.5 2.0 + 0.5’

0.5 f 0.8 34 4 20

0.5 + 0.8 34 4 17

Conclusion: Despite similar angiographic follow-up, supporting

(N=3n)

worse baseline characteristics, diabetic patients had and clinical outcomes as non-diabetics at 6-month the use of IRT in diabetic patients with ISR.

A94

49th Annual

Scientific

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of CSANZ

Heart,

A COMPARATIVE ANALYSIS OF OUTCOMES OF CORONARY INTERVENTIONS IN OCTOGENARIANS VS THE ELDERLY: R.P. Tan*. M. Kamran. C. Mitre. A.S. Kini. S.K. Sharma. Cardiovascular Institute, Mt Sinai Hospital, New York, New York. Limited data is available on outcomes of percutaneous coronary interventions (PCI) in octogenarians in the present era of widespread use of stents and abciximab. We analyzed and compared baseline clinical, angiographic and procedural results of 348 consecutive octogenarians (mean age 84.024.2 yrs and 52.8% males) with those of 1132 consecutive elderly patients aged 65-79 yrs (mean age 71.7r4.1 yrs and 55.9% males) undergoing PC1 at the Mt Sinai Hospital from Jan 1997-Dee 1998. The octogenarian group had a higher incidence of Canadian Cardiovascular Society Angina Class 4, left main disease, LVEF<45%, hypertension, history of CCF, recent MI
Elderly (65-79 yrs) xl=1132 95.7 Angiographic success (96) Clinical success (%) 95.2 Major complications (%) 0.5 CKMB 13x normal (%) 0.8 Vascular access complications (%) 2.0 0.3 Cerebrovascular events (%) Mean length of stay (LOS) post 2.6+4.8 PC1 (days) ns = not significant

Octogenarian n=348 97.1 94.8 2.3 2.0 3.2 0.0 3.Ok4.5

p value

Conclusion: Octogenarians undergoing PC1 in higher risk of major complications due to their profile. However, a very high clinical success group with no significant increase in vascular post PC1 when compared to the rest of the elderly

the present era remain higher baseline clinical rate can be achieved in complications or mean population.

ns ns p
at a risk this LOS

TRANSRADIAL CORONARY INTERVENTION IN OCTOGENARIANS JX.P. Tan*. I.D. Hilton, A.T. Clark. P.M. Smith. W.I? Klinke. Cardiac Catheterization Lab, Royal Jubilee Hospital and Victoria Heart Institute Foundation, Victoria, British Columbia, Canada. Limited data is available on the efficacy and safety of transradial coronary intervention (TRCI) in octogenarians. Method: We present our experience in 85 consecutive octogenarians undergoing TRCI from July 1998 till June 2000. This group comprised 46% of all octogenarian interventions over this period. Patients with cardiogenic shock (n=l) and failed radial artery access (n=13) were excluded. Results: Baseline characteristics; male 65.9%, mean age 83.3k2.6 yrs, hyperlipidemia 62.3%, previous cerebrovascular accident (CVA) 10.6%, unstable angina 52.9%, recent myocardial infarction (MI) 15.3%, old MI 42.3%, Canadian Cardiovascular Society Angina Class 3-4 91.8%, 2 or 3 vessel coronary artery disease 75.3%, mean left ventricular ejection fraction 54.3+14.7%. Procedural data; urgent 68.2%, de novo lesions 92%,no of lesions 127, stent procedures 74.1%, lesion type B2 62%, lesion type C 29%, abciximab use 18.8%, pre-minimal luminal diameter (MLD) 0.32+0.34 mm, post-MLD 2.78r0.82 mm, mean flouroscopy time 16.2klO.l mins, contrast volume 205t82 mls. Procedural results; angiographic success 97.6%, clinical success 96.5%, death 1.2%, Q wave MI 1.2%, emergent CABG 0%, non Q wave MI 2.4%, CVA 1.2%, vascular access complications 3.5%, mean length of stay postTRC1 1.7k2.8 days, same day discharge postTRC1 36.5%. Follow-up: 30 day major adverse cardiac event 1.2%, survival and event free survival at 6 months were 92.9% and 81.1% respectively. Conclusion: TRCI can be performed with a high success rate, reduced length of stay and a good long-term outcome in a significant proportion of octogenarians.

Lung

and Circulation

2001; 10

CLINICAL OUTCOME OF LONE ATRIAL FIBRILLATION COMPARED WITH AF ACCOMPANYING OTHER CARDIAC CONDITIONS M.A. Barlow*, John Hunter Hospital, Newcastle; G. University of Western Ontario, London; A. Oi. CR. Kerr. 1.B. Boone, St. Paul’s Hospital, Vancouver; S.T. Connolly, MacMaster University, Hamilton; P. Dorian, St. Michael’s Hospital, Toronto; M. Green, University of Ottawa, Ottawa; M. Talajic, Montreal Heart Institute, Montreal; and R. Sheldon, University of Calgary, Calgary. Objective: To compare the outcome (thromboembolism (TE) and death) of lone atria1 fibrillation (LAF) patients (pts) with that of pts with atria1 fibrillation (AP) accompanying other conditions. Methods: Prospective follow-up of 980 patients from the Canadian Registry of Atria1 Fibrillation. Pts were grouped into LAF, AF and cardiovascular disorders (CARDIAC), AF post cardiothoracic surgery (CTSURG), and AF accompanying non-cardiac disease (NCNLAF). Follow-up occurred annually for 5 years. Results: See table. Patient # Follow-up (mths) Age (~1s) BP-systolic BP-diastolic TIA Stroke/Embolus Total TE Death

LAF 132 51.9 t 15.2 53.0 r 15.0 127.0 f 17.1 75.6 * 10.2 5 (O.S%/yr) 3 (0.5%/yr) 8 (1.4%&r) 2 (0.4%/yr)

NCNLAF 72 52.4 k 14.0 57.1 + 17.9 127.6 + 19.7 77.2 t 14.6 1 (0.3%/yr) 3 (l.O%/yr) 4 (1.3%/yr) 5 (1.6%/yr)

CTSURG 179 51.6 k 13.4 63.9 f 9.7 123.0 + 18.6 67.8 f 10.7 9 (1.2%/yr) 6 (0.8%/yr) 15 (Z.O%/yr) 12 (1.4%/yr)

CARDIAC 597 46.1 + 18.1 65.1 + 12.1 138.1 + 26.4 84.3 + 16.3 25 (l.l%/yr) 45 (Z.O%/yr) 68 (3.l%/yr) 112 (4.9%/yr)

There were no significant differences in total TE rate between the groups. The average warfarin usage during follow-up in the LAF, NCNLAF, CTSURG and CARDIAC groups was 23.0%, 22.5%, 24.7% and 34.8% respectively. Compared with the LAF group, mortality was significantly higher in all other AF groups - p < 0.05 for NCNLAF and CTSURG groups, p < 0.0001 for CARDIAC group. Conclusion: In comparing LAF pts with those in whom AF is associated with other conditions, survival is significantly better but the risk of thromboembolism is only slightly lower.

THROMBI FORMATION PHYSIOLOGIC STUDIES Hospital, Westmead N.S.W.

ON CATHETERS USED DURING L.M. Davis* Cardiology Department,

ELECTROWestmead

Electrophysiologic (El’) studies usually have an extremely low morbidity and mortality rate but are becoming more complex with the need for direct mapping of left heart structures increasing the risk of thrombotic complications. Thrombi forming on mapping catheters or inside venous sheaths may contribute to this risk. To help elucidate the extent of this problem, qualitative assessment was performed of the presence and amount of thrombus (Th) on EP catheters and in venous sheaths at the conclusion of routine EP cases. Catheters were inserted via Triport 14French sheaths. in the femoral vein. The sheath and all the catheters were removed as a unit at the end of the case and examined for thrombus. Five patients had no anticoagulation but frequent flushing of the sheath ports with heparinised saline, one patient was on full dose warfarin and 10 patients had 1000 I.U. heparin infusion per hour in addition to periodic flushing of the sheath ports. Results: Diffuse thrombus formation was often observed over the venous extent of the catheters in the triport sheath but not in the triport sheath itself and not on catheters introduced through other sheaths matched to the catheter size. AWiCO~gUl&iOll Short Study (3 Wire) Long Study (4 wire) NoTh Minor Tb LargeTh NoTh Minor ThLargeTb 1 Warfarin N=l 3 1 2 3 Heparin Infusion 1 0 1 3 Heparin flushes 1 0 Conclusions: Thrombi frequently form on catheters especially during prolonged cases and may occur even if the patient is fully anticoagulated. If left heart catheterization is planned this should be performed early in the case without disturbing right heart catheters if possible

Heart, Lung and Circulation

49th Annual Scientific Meeting of CSANZ

2001; 10

A95

ATRIAL PACING THRESHOLDS ARE AS STABLE AS VENTRICULAR THRESHOLDS AT ONE YEAR AFTER IMPLANTATION. W Saw’. it h. Cardiovascular >I’ H ref Id-Ash1 Department. John Hunter Hospital. Newcastle, New South Wales, Australia.

CHANGES IN DICTOR OF y V.B r and Repatriation

Introduction: It is well established that atria1 pacing lead thresholds are higher than ventricular thresholds at the time of implantation, however whether this trend continues with the passage of time is unclear.

Whether heart rate variability (HRV) can predict a neurocardiogenic response to tilt table testing (TIT) remains unclear. We performed HRV supine and then standing at 70 degree tilt for ten minute periods in 31 patients, mean age 61(20-89 years), undergoing m for suspected neurocardiogenic syncope. Patients were asymptomatic during this assessment, but subsequently underwent further tilt table testing with an isoprenaline infusion, producing a positive neurocardiogenic response in 14 (45%) patients. Overall HRV was assessed in the time domain using SDNN(standard deviation of all NN intervals) and RMSSD( square root of the mean of the sum of squared differences between adjacent NN intervals) respectively Postural changes in vagal tone were measured using high frequency (HF) spectral analysis and sympathetic activity measured using the low frequency (LF) spectrum. The supine, erect and postural change in HRV were compared between positive and negative responders to TIT using ANOVA with Bonferroni adjustment. Results: Normal postural physiological changes in HRV were noted with decreased vagal tone (HF, p= 0.06) and increased sympathetic tone (LF, p= 0.000). Younger patients (n=17, <=70 years) displayed greater postural heart rate fluctuation (median RR, p= 0.016) but were no different to older patients (n= 14, >70 years) in their vagal or sympathetic responses. However, neither HRV supine, HRV erect, nor postural change in HRV predicted the subsequent TTT results. No gender differences in TIT positivity were shown. Conclusion: In this study, although there were physiological and age related postural changes in HRV induced by tilting, HRV was unable to predict the outcome of a TTT during pharmacological challenge.

Method: We retrospectively studied 31 patients who received dual chamber pacemakers with passive atria1 and ventricular leads during 1999. The atria1 and ventricular pacing thresholds were reviewed at the time of implantation, 3 months, and 12 months. Unpaired Student T Test was used to analyze the data. Results: Atria1 thresholds were higher than ventricular at the time of implant [0.64+/-0.24 Vs 0.4+/-0.13 l’= O.OOOl]. Thresholds at three months after imulant and at 12 months are shown in following table. Atrial pacing threshold Ventricular pacing threshold r value

At implant

At 3 months

O&4+/-0.24 0.40+/-0.13

0.74+/-0.64 0.55+/-0.16

At 12 months 0.71+/-0.47 0.60+/-0.26

r=0.0001

lko.12

P=O.28

Conclusion: Although atria1 thresholds at the time of implant were significantly higher than ventricular, the degree of increase in threshold was considerably less in atria1 leads at 3 and 12 months. Although this is a relatively small study, the finding suggests atria1 pacing thresholds are at least as stable as ventricular at 12 months of implantation. Larger studies are needed to support this view.

COUGH SYNCOPE: CLINICAL AND INVESTIGATIONAL SEVEN PATIENTS. G Trim’, S Nicholls. W Saw. M Barlow, ment of Cardiovascular Medicine, John Hunter Hospital, South Wales.

HEART RATE A POSITIVE Medical

VARIABILITY WITH POSTURE - A PRETILT TABLE TEST? A.W.F. Hamer”, Department of Cardiology, Austin Cente, Heidelberg,Vic.

PROFILE OF 1 Leitch. DepartNewcastle, New

ACTIVE VENTRICULAR LEADS ARE MORE LIKELY TO CAUSE RBBB LIKE MORPHOLOGY IN PACED RHYTHM G Trim*. S Nicholls. W Saw J Leitch, M Barlow Department of Cardiovascular Medicine, John Hunter Hospital, Newcastle, New South Wales.

Introduction: Cough syncope is a form of syncope which is thought to be due to a reflex-mediated cardioinhibitory and/or vasodepressor response to coughing, leading to a transient loss of consciousness. The clinical correlates of this condition and the usefulness of investigations are still relatively poorly understood. Method: We reviewed and analysed the medical records of seven patients with a history of typical cough syncope (defined as syncope during paroxysms of coughing but not at other times), including their age, gender, weight, smoking history, comorbidity, and investigations performed. Results: All seven patients were male. The average age was 53 years (range 38-68 years). Average weight was 85 kg (range 67-104 kg). Five of the seven (71%) had a smoking history; six (86%) had chronic airways disease, five due to smoking and one due to asthma. All had normal ECGs. Four had echocardiograms, two of which were normal, and two of which showed evidence of diastolic dysfunction. Carotid sinus massage was normal in all patients. Tilt table testing was negative for vasodepressor syncope in all seven patients. Two of three in whom coughing was induced experienced syncope or presyncope in association with documented hypotension. One of five in whom the Valsalva manouevre was performed had their presyncopal symptoms reproduced in association with hypotension. Conclusion: Cough syncope typically occurs in middle-aged men with chronic airways disease. Tilt table testing was negative in all seven patients and hence is not a sensitive diagnostic test for susceptibility to this condition. Induction of coughing and performance of the Valsalva manouevre may have some diagnostic value. Diagnosis remains primarily clinical, however, and based on the characteristic history. Treatment is difficult but usually involves measures to reduce coughing spells, and smoking cessation. The lack of sensitivity of the tilt table test suggests that the mechanism of syncope in this condition may be other than reflex-mediated.

Introduction: Active (or screw-in) ventricular pacing leads may be employed due to perceived greater ease, security and flexibility of placement. Passive (tined) leads positioned in the right ventricular apex are usually expected to produce a LBBB-like morphology on the 12-lead ECG in paced rhythm. RBBB-like morphology raises the concern that the lead is incorrectly placed, either in the coronary sinus or in the left ventricle via a patent foramen ovale. We compared the ECG morphology in paced rhythm of active and passive ventricular leads, because it is our impression that active leads are more likely to produce RBBB-like morphology than passive leads. Method: The 12-lead ECGs in paced rhythm of 25 active and 25 passive ventricular pacing leads were compared. The ECG morphology was classified as either LBBB-like (dominant S wave in Vl and V2, with transition to dominant R wave in V4 or later) or RBBB-like (dominant R wave in Vl and/or V2). The active leads employed were Medtronic 5068 and the passive leads were Medtronic 5024. All leads were correctly placed in the right ventricular apex as judged by PA and lateral chest x-ray. Results: Nine of 25 active leads (36%) produced RBBB-like morphology, whereas only one of 25 passive leads (4%) produced RBBB-like morphology This result was statistically significant (p=O.O4 by a-tailed Fisher’s exact test). Conclusion: Thirty-six percent of active leads in the right ventricular apex produced a RBBB-like morphology compared with only 4% of passive leads. Presumably the active lead screw, which protrudes 2-3 mm from the tip of the lead, is responsible for a left to right septal activation pattern rather than the reverse, which is typically seen with passive leads. Therefore, providing correct lead position is confirmed on PA and lateral chest x-rays, RBBB-like morphology need not cause concern that an active ventricular lead is incorrectly placed.

A96

49th

Annual

Scientific

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of CSANZ

Heart,

Lung

and Circulation

2001;

10

IS CONTRACTILE RESERVE RELATED TO LONG-TERM SURVIVAL POST AORTIC VALVE REPLACEMENT IN PATIENTS WITH LOW GRADIENT SEVERE AORTIC STENOSIS AND LEFT VENTRICULAR DYSFUNCTION JJ Pereira*. M Bashir, I Afridi. ID Tho mas. CR Asher. The Cleveland Clinic Foundation, Cleveland, Ohio, USA.

EXCIMER LASER CORONARY ANGIOPLASTY AND RADIATION FOR IN-STENT RESTENOSIS: 6-MONTH ANGIOGRAPHIC AND CLINICAL OUTCOMES A E Ajani’. H-S Kim. L F Saber. A D P ichard. K M Kent and R Waksman Washington Hospital Center, Cardiovascular Research Institute, Washington DC

Objective: Among patients (pts) with severe aortic stenosis (AS), elevated transvalvular gradients and left ventricular (LV) dysfunction, aortic valve replacement (AVR) is associated with improved left ventricular ejection fraction (LVEF) and survival. We sought to determine if contractile reserve in pts with low transvalvular gradient (TVG) severe AS and severe LV dysfunction is related to long-term survival. Methods: We identified 63 consecutive pts who underwent AVR between 1990-98 with aortic valve area < 0.75cm2, mean gradient < 3OmmHg and LVEF < 35mmHg. Short and long-term survival has been previously reported. Of 60 peri-operative survivors, post-operative (post-op) echocardiography (echo) was obtained early post AVR (11+14 days) in 48 (80%) pts, and late post AVR (354*318 days) in 27 (45%) pts. Change in LVEF and its relation to long-term survival was assessed. In pts with early post-op echo, the relationship between pie-operative (pre-op) variables to post-op LVEF was analyzed. Results: Pre-op variables in pts who did and did not receive early or late post-op echo showed no significant differences in age, sex, NYHA class, transvalvular gradients, severity of coronary artery disease (CAD), or length of follow-up. In the 48 pts with early post-op echo, LVEF improved from 21r7% to 28i9% (p 10% early or late post-op was not associated with increased long-term survival. Pre-op variables related to improved early postop LVEF by > 10% were female sex (p = 0.05), absence of hypertension (p=O.O3), smaller LV dimensions (p = 0.04), and coronary bypass surgery in addition to AVR at operation (p=O.O5). However neither aortic valve gradients or area, nor severity of CAD were significant determinants of post-op LVEF. Conclusions: Although there is a modest improvement in LVEF post AVR in pts with low TVG severe AS and severe LV dysfunction, other mechanisms for long-term survival may be important.

Background: The purpose of this study was to evaluate 6-month clinical & angiographic outcomes in patients (pts) treated with excimer laser coronary angioplasty (ELCA) & intra-coronary radiation (ICR) for in-stent restenosis (ISR). Methods: A consecutive series of 175 pts with ISR treated with ELCA & ICR (gamma & beta emitters) were compared to 33 patients with ISR treated with ELCA alone. Baseline characteristics were similar between groups. ELCA & ICR and ELCA alone pts had similar lesion lengths 25.0 + 12.0 vs. 24.0 + 16.8 mm (p=NS), in pmdominantly saphenous vein grafts (38% vs. 42%, p=NS). Results: The procedural success was high (ELCA & ICR, 97.0% vs. ELCA alone, 98.5%, p=NS), with no perforations or acute vessel closures. The frequency of clinical events at 6 months are outlined in the Table. Late loss was 0.66 f 0.90 mm in ELCA & ICR pts & 0.85 + 0.60 mm in ELCA alone pts (p=NS). Angiographic binary restenosis (>50%) was reduced with ICR (28% vs. 54%, p=O.O14).

SUSPECTED BACTERIAL ECHOCARDIOGRAPHY Department of Cardiology,

ENDOCARDITIS - IS TRANSOESOPHAGEAL USED RATIONALLY? M Wilson l , Al Bovle St Vincent’s Hospital, Melbourne

Introduction: Transoesophageal Echocardiography (TOE) has great utility in assessing complications of bacterial endocarditis (BE), in assessing patients with suspected prosthetic valve endocarditis (PVE) and patients in whom non diagnostic images are obtained with transthoracic echocardiography (TTE). However TOE is invasive, not universally available and requires a trained cardiologist and other staff present. There is minimal evidence that TOE is significantly superior to TTE in assessing most patients with suspected BE. Aim: To review the findings in patients referred for TOE with suspected BE and assess clinical features, outcomes and whether TTE was performed in the diagnostic process. Methods: All patients (n=117) referred with suspected BE between 22/3/99 and 22/3/00 were included and reviewed for demographics, blood culture and inflammatory marker results, presence of fever and other clinical information Findings of TIE (where done) and TOE were compared. Patient outcomes of surgical intervention, death and medical management were assessed. Results: 14 patients had positive results on TOE (11.5%). Of these 2 had PVF 2 patients required surgery for haemodynamic reasons and one died post operatively. Only 2 of 14 had a TTE prior to the TOE and 2 had a positive TOE at another institution. In both cases the vegetation was seen on TIE. 10 had positive blood cultures and all had clinical valve disease and significantly raised inflammatory markers. In patients with negative TOE, only 14 had TTE prior to TOE (13.6%). This patient group included groups of patients who had minimal diagnostic criteria for BE such as intravenous drug users with fever (n=6), follow up of staphylococcal septicaemia (n=14 patients), other septicaemia with obvious focus (n=16) and oncology patients with fever (n=4).These groups almost all had TOE as the initial investigation. Conclusion: TOE was ordered as the initial and often only investigation in large groups of patients with low probability for BE. TOE did not appear to alter patient outcome in low risk patients and was overntilised. TIE was underntilised.

ECLA & Radiation (Nd7E.J Death, % Q-wave MI, % Non-Q-wave MI, % TLR, % TVR, % Late Total Occlusion, % MACE (TVR), %

4 1 21 18 27 4 30

ECLA & Placebo (N=33) 3 0 15 64 64 3 64

P NS NS NS <0.0001 <0.0001 NS 0.0002

Conclusion: Radiation therapy with ELCA significantly reduces angiographic binary restenosis and composite MACE at 6 months in patients with diffuse in-stent restenosis, driven predominantly by reduced percutaneous target vessel revascularization.

BETA VERSUS GAMMA RADIATION THERAPY FOR PATIENTS WITH IN-STENT RESTENOSIS: A COMPARISON BETWEEN TWO EMITTERS BASED ON CLINICAL TRIALS A E Aiani’. R Waksman. L F Satler. A D Pichard. K M Kent. M Porrazzo. R Lawrence White Washington Hospital Center, Cardiovascular Research Institute, Washington DC. Background: Intracoronary radiation therapy (IRT) using beta & gamma emitters has been shown to reduce recurrent in-stent restenosis (ISR). The purpose of this analysis was to compare the effect of these emitters for the treatment of (< 20mm) ISR lesions. Methods: Seventy-nine patients (pts) from the Beta trials START and START 40/20 (9OSr/Y), BETA WRIST (9OSr/Y), INHIBIT and BRITE (32P) were compared to 115 pts from the gamma trials: WRIST (Washington Radiation for In Stent restenosis Trial), GAMMA-l & -2 and ARTISTIC using 192Iridium. All pts completed g-month clinical follow-up. Results: The demographic & angiographic details were similar in both groups, except less rotational atherectomy (29% vs. 52% p = 0.002) was used in beta pts. The mean lesion length was 11.8 + 4.3 mm in the beta group & 12.0 f 4.5 mm in the gamma group (p = NS). The prescribed dose in the beta studies was 16 or 20 Gy at 2 mm (mean 17.3 e1.9 Gy) & in the gamma studies 14-18 Gy at 2 mm (mean 14.7 ? 0.5 Gy). IRT was delivered successfully in all but one pt (beta), and was well tolerated with a mean dwell time of 3.7 * 0.5 minutes for beta versus 22.1 t 4.2 minutes for gamma. Antiplatelet therapy was at least 3 months for all beta patients and 1 or 2 months in the gamma trials. No differences were detected in hospital events between beta and gamma treated patients. At 8 months, TLR (15% vs. 18%, p = NS), TVR (22% vs. 22%, p = NS) and MACE (20% vs. 24%, p = NS) were comparable with beta and gamma emitters. Conclusion: IRT using both beta & gamma emitters is effective in reducing the recurrence rates of ISR. Comparison of clinical trials demonstrates equivalence in efficacy & safety for both emitters for the tmatment of lesions 5 2Omm in length.

Heart,

Lung

and Circulation

2001;

49th

10

BALLOON ANGIOPLASTY IS SUPERIOR TO RE-STENTING STENT RESTENOSIS. E KotscheP A4 Krawczvsrvn. A Browhton.

FOR IN-

D Haikenval, Cardiovascular Medicine, A&d Hospital, Melbourne. Australia Aim To determine the outcomes of interventional management for in-stent restenosis. Methods The Alfred Hospital computerised angioplasty database was examined retrospectively. We reviewed the records of all patients undergoing interventional procedures between 01/08/1997 and 30/10/2000. m A total of 2258 lesions were revascularised; 1778 were stented (S), 451 had balloon angioplasty (P) and 22 had a rotablator procedure(R) (choice of device at operators discretion). 90 (4. I%) patients developed clinical restenosis. The clinical re-stenosis rate was 5.1% after P and 3.8% after S (67 lesions). Re-intervention with S, P or R for the lesions with in-stent re-stenosis achieved long term clinical success in 66%. 39% in-stent re-stenosis treated with S developed recurrent re-stenosis compared to 14% where the second procedure was P. In the group with recurrent in-stent re-stenosis (21 lesions) 2 had medical management, I2 CABG, 4 S, I P and 2 R. The lesion site was similar in both S/S and SIP groups. 2258 Total No. Lesions I 1178 451 Procedure (3 k (P) In-Stent Stenosis

l67 S (SIR)

Procedure CF= F&d procedure,

21

:SIF)

(S/P)

I I I 3 3 In-Stent Restenosis 15 Discussion In stent re-stenosis is an important complication of stem insertion. New strategies being developed include brachytherapy, however the current strategy is P or S. Our data suggests that in-stent re-stenosis is more likely to recur after re-stenting than re-ballooning (39% v l5%, p=O.O4). Conclusion In-stent re-stenosis can be managed effectively with balloon angioplasty without the need to insert a “stent in a stent”.

Percutaneous revascularization (PR) of saphenous vein grafl (SVG) stenoses is associated with high rates of restenosis. Although endoluminal radiation therapy (ERT) reduces restenosis in native vessel lesions, there is limited data evaluating the role of this therapy in SVG disease. To date all reported trials of beta ERT have excluded SVG lesions. This study evaluated the efficacy of acljunctive ERT with the high-energy, p-emitting, liquid radioisotope Rhenium (lssRe) following PR of instent restenotii lesions Following

successful

revascularization

(10 rotablator/PTCA.

3

restented), 13 patients (mean age 63i7 years) have been treated in this open-label pilot study (7/99-l lxx)). An average of 2.1~o.8 prior procedures had been undertaken to culprit lesions of maan length 12*5mm. IVUS guided the delivery of a radiation dose of 25 Gy (OSmm from the balloon surfatx~ achieved by inflation of a conventional sngioplasty balloon with liquid Reperrhenate (mean activity 6.6i0.7 GBq/ml) in all cases. Average dwell time was 289+83 seconds with tandem treatment performed in 1 case. Mean radiation length was 34il7mm. Follow-up entails clinical review at 30 days and 12 months and angiographic review at 9 months. All procedures were uncomplicated with na major in-hospital dinical events. Radiation was successfully delivered in all patiints and there was no case of balloon rupture or internal ‘-Re release. At the mean follow-up of 11.5 (range 3-18) months, 77% of patients remained event-free. There have been no deaths. late stent thromboses or AMIs. Two patients (15%) required -get vessel revascularization (redo CABG in one case and PR in the other). One patient required non-target vessel revascukization (PR). Routine 9 month angiography has been performed in 7 patients (54%) to data, demonstrating

patent treatment requiring

sites in all oases.

PR at 12 months.

inflation of a conventional

Them was one moderate

Beta-ICRT

angicplasty

using

liiuid

‘“Re

edge-lesion delivered

balloon catheter is technically

CORONARY OF IN-STENT

by

feasible

for treating SVG disease. Preliminary findings indicate this treatment to be effedive in preventing reMTent instent rest-is in SVG lesions. These early results are partiakidy encouraging in view of the high recurrence rates after PR and limited treatment optiins often available to patients with degenerative SVG disease.

Scientific

Meeting

SYNDROME IS A COMMON RESTENOSIS D L Walters*.

, IK-Kyunp Tang Cardiology Division, Massachusetts vard Medical School, Boston, Massachusetts, USA.

A97

of CSANZ

CLINICAL

PRESEN-

S A Harding. C R Walsh General Hospital, Har-

The early detection of vulnerable coronary plaques for the prevention of acute coronary syndromes including acute myocardial infarction, has been the focus of recent research efforts. Currently, stenting is the most likely choice of local therapies for the treatment of vulnerable plaques. However, unlike patients with restenosis following balloon angioplasty, clinical presentation of patients who develop restenosis following stenting has not been well defined. In this study we compared the clinical presentation of instent restenosis with that of percutaneous coronary intervention (PCI) without stenting. Methods: Among a total of 740 patients who underwent PC1 and had repeat catheterization between 10/l/97 and 6/30/00,262 consecutive patients with recurrent ischemia and restenosis were identified: 191 patients with stenting (Group A) and 71 without stenting (Group B). Patients who underwent interventions in bypass grafts and those who developed acute stent thrombosis were excluded from the study. Results: The baseline characteristics of the two patient groups were similar. Recurrent clinical ischemia occurred at a mean of 5.5 months for Group A and 6.4 months for Group B (p=O.24 ). Rest angina was more frequent in Group A (48 vs 32 %,p
DIRECTIONAL CORONARY TIONAL ATHERECTOMY RESTENOSIS OF NATIVE

ENDOVASCUIAR BETA-RADIATION THERAPY FOR THE PREVENTION OF INSTENT RESTENOSIS IN SAPHENOUS VEIN GRAFT LESIONS. N Jeoson’. C Milross. D Lm n. C Karolis. C Friend. S Anad ides , T KnitI& R Allan. M p ihey. Prince of Wales Hospital, Sydney, NSW.

in SVGs.

ACUTE TATION

Annual

ATHERECTOMY IS SUPERIOR TO ROTAFOR THE TREATMENT OF IN-STENT CORONARY ARTERIES P L. Sanchez,

M Rodrieuez-Alenuarle, P T Colon-Hemandez. D L Walters *, E Pomerantsev, I Inzlessis. , N A Mahdi. . R C Leinbach. I F Palacios Cardiology Division, Massachusetts General Hospital, Harvard Medical School, Boston.USA. Management of in-stent restenosis has become a significant challenge in interventional cardiology. Since the mechanism of in-steni restenosis is predominantly intimal hyperplasia, debulking techniques may offer a therapeutic advantage. Methods: We compared the immediate and long-term results of directional coronary atherectomy (DCA; n=58) vs. high-speed rotational atherectomy (ROTA; n=61) for the treatment of in-stent restenosis of native coronary arteries. Background:

Results: There were emergency coronary

no in hospital artery bypass

deaths,

Q-wave

myocardial

infarctions

or

surgery in either group. DCA resulted in a larger post procedural minimal luminal diameter of (2.57 + 0.51 mm vs. 2.14 + 0.37 mm; p
A98

49th Annual

Scientific

Meeting

of CSANZ

Heart,

THE EFFECT OF DIABETES MELLITUS ON IN-HOSPITAL OUTCOMES AFTER PRIMARY CORONARY ANGIOPLASTY. HMO Farouaue*, JL1 K ale redith. Cardiovascular Research Centre, Monash Medical Centre, Melbourne. Despite recent advances in pharmacotherapy, diabetes mellitus remains an independent predictor of poor outcomes after acute myocardial infarction (AMI). Primary coronary angioplasty (PCA) is a proven reperfusion strategy in this setting, but there is limited data on the efficacy of this approach in diabetic patients. We performed a retrospective review of procedural and clinical in-hospital outcomes in diabetic patients (DM) treated with PCA, and a control group of non-diabetic patients (NDM) matched for age and sex, presenting within 12 hours of symptom onset. Clinical and angiographic data (QCA-CMS, MEDIS ~4.1) were examined in 29 diabetic (age 63+11 years, 55% male) and 31 non-diabetic patients (age 61rlO years, 63% male). Baseline characteristics are presented below. Variable Location of AMI Anterior Inferior Cardiogenic shock lime from symptoms to reperfusion Mutivessel coronary disease Percent stenosis

DM

(min)

Lesion length (mm) TIMI 0 flow grade Culprit vessel reference diameter (mm)

NDM

P value 0.31

10 (34%) 18 (62%) 11 (38%) 237r22 16 (55%) 97tr1

16 (50%) 16 (50%) 11 (34%) 254t27 18 (56%) 9&l

0.77 0.62 0.68 0.40

10.8*1.3 17 (63%) 3.4+0.1

11.8-tl.9 20 (77%) 3.3t0.2

0.69 0.15 0.61

Successful PCA (residual lumen diameter < 50%, TIM1 3 flow) was achieved in 90% of DM and 88% of NDM patients (P=O.25). Clinical success (successful PCA without death, recurrent AMI or revascularisation) occurred in 69% of both groups (86% NDM versus 89% DM in patients without cardiogenic shock, P=O.77). Death during the index admission occurred in 24% of DM and 19% of NDM patients (P=O.61). Usage of stents (P= 0.72) and GPIlb/IIIa antagonists (P=O.99) were similar in both groups. There was no difference in occurrence of groin haematoma and peak creatine kinase levels post procedure. Length of stay was also similar (7+1 versus 6?1 days, NDM versus DM). In a well-matched population of high-risk diabetic and non-diabetic patients referred for mechanical revascularisation in the setting of AMI, short-term procedural and clinical success was comparable. LATE STENT THROMBOSIS AFTER INTRACORONARY BETA RADIATION IN PATIENTS WlTH INSTENT RESTENOSIS N Jeoson’. C Friend. R Atlan. C Karolis. C Milross. S Anoeliis. D I oneman. T Kninel. M Pitneu, Prince of Wales Hospital, Sydney, NSW. Although intracoronary radiation therapy (ICRT) is highly effective in reducing the rea.rnence of instent restenosis (ISR), reports of excessive late stent thrombosis (~30 days after ICRT) leading to AMI (incidence between 615%) have raised concerns over the safety of this therapy. Late stent thrombosis (LST) has bean strongly associated with new stent implantation A comprehensive and early discontinuation of anti-platelet therapy. endovascular brachytherapy programme has bean developed at the Prince of Wales Hospital. This study reviews the hospital’s complete ICRT experience in patients (pts) with ISR enrolled in radiation trials or treated with a commercially available device. Following successful revasculartzation (additional stenting required in 30%) 90 lesions in 64 pts in native vessels (66%) and vein grafts (14%) received beta radiation between 5/99-11103. The radioactive isotopes utilized were - liquid ‘%Re delivered by a PTCA catheter in 64 (76%) “P wire in 17 (20%) and g”Sr/mY seeds delivered by the Eata-Cath system in 3 (4%). Clopidogrel was continued (75mglday) for 3 months (mths) in pts who did not receive new stents and for 6 mths (75mgldey) in those receiving new stems. All pts receive aspirin indefinitely, undergo angiographic review at 9 rqths and are followed clinically. Revesculatization and ICRT procedures were uncomplicated with no major in-hospital events. Current follow-up time is >6 mths in 70% of pts and >I2 mths in 40% of pts. There have been no deaths and no cases of subacute stent thrombosis (< 30 days). There have been 3 LSTs (3.6%). All presented with AMI but only one of these received a new stent. The mean time to LST was 3.3 mths. One LST occurred on clopidogrel (restented case) while dopidogrel had been ceased in the remainder (treatment was curtailed in one case due to haemorrhagic pancreatitis but the other had completed the required course). Clopidogrel therapy was well tolerated by all pts and there was no report of neutropeenie OT thrombocytopaenia. There was one late total occlusion that presented at 4.5mths with stable angina. Prolonged antiptatelet therapy with dopidogrel and minimizing new stent implantation for pts with ISR treated with beta-ICRT is associated with a reduction in the rate of LST compared to historical controls. An increased duration of clopidcgrel therapy is being considered (6 mths if no new Stent is implanted and 12 mths if new stents are required).

Lung

and Circulation

2001; 10

THE EFFECT OF THE RENIN-ANGIOTENSIN-ALDOSTERONE SYSTEM GENE POLYMORPHISM ON CORONARY IN&TENT RESTENOSIS. S K Ryu’. H Y Park. E K Lim. Y Tane W H Shim. S Y Cho. Yonsei Cardiovascular Hospital and Cardiovascular Research Institute, Yonsei University College of Medicine In-stent restenosis is one of the most important prognostic factors in patients with coronary artery obstructive disease after intracoronary stent implantation. The intima proliferative model is recognized as a leading mechanistic theory of restenosis after stenting. The over excretion of angiotensin II and aldosterone, due to abnormality of the renin-angiotensin-aldosterone system, is reported to be a possible cause of cardiovascular tissue proliferation, left ventricular hypertrophy, and hypertension. As polymorphisms of angiotensin I-converting enzyme (ACE), angiotensinogen (AGT), and aldosterone syn thase (CYPllB2) are related to the high activity of each hormone, therefore, there are possibilities that the genes may affect the prognosis of in-stent restenosis. We analyzed genotypes of 241 patients who underwent intracoronary stent implantation and follow-up coronary angiography from year 1998 to 1999. And the outcome of 272 stents in these patients, past histories, and characteristics of the lesions were reviewed. The results were as follows; 1. No significant differences in terms of sex and age were found between the two groups. 2. The results of QCA revealed that the risk of in-stent restenosis increased with the lesion length and was inversely proportional to the lesion diameter. 3. The distributions of genotypes were ACE I/D : 11(81/33.6%)/1D(105/43.6%)/DD (41/17.0%), CYPllBZ-344C/T : TT(lO9/42.3%)/CT(lO9/42.3%)/CC (21/8.7%), and AGT M235T : MM(38/15.8%)/MT(72/29.9%)/ TT(ll9/49.4%). 4. In the case of ACE DD genotype, follow-up MLD was significantly smaller than in those of II or ID genotypes by independent sample t-test (~~0.05). Also, in lesion with followup MLD < 2 mm, the ACE DD genotype was more frequent than the others. 5. There was no significant correlation between CYPllB2-344C and AGT M235T polymorphism and restenosis after stenting. 6. Synergistic effects of ACE, CYPllBP, and AGT gene polymorphisms upon in-stent restenosis were not found in either a recessive or dominant manner. As described above, ACE I/D polymorphism promoted the progress of in-stent restenosis and was of clinical significance, but the other potential variables examined did not correlate with in-stent restenosis.

SUPERIORITY OF PLASMA AMINOTERMINAL BNP OVER LEFT VENTRICULAR EJECTION FRACTION FOR PROGNOSIS AFTER MYOCARDIAL INFARCTION. A.M. Richards*, M.G. Nicholls. E.A. Esoiner. R.W. Trouehton, I.G. Lainchburv, 1.M. Elliott. LG. Crazier. C. Framuton. 1.G. Turner, T.G. Yandle Christchurch Cardioendocrine Research Group, Christchurch School of Medicine, and Departments of Cardiology and Nuclear Medicine, Christchurch Hospital, Christchurch, New Zealand. In 666 patients with myocardial infarction (MI), plasma N-BNP and radionuelide LVEF both predicted death (p
Heart,

Lung

and Circulation

2001; 10

INCREASED MtDNA MUTATION RATE IN HUMAN MYOCARDIUM ASSOCIATED WITH AGEING, POST-ISCHEMIC CONTRACTILE DYSFUNCTION AND POSTOPERATIVE ATRIAL FIBRILLATION Rosenfeldt FL”. Miller FLZ Mariani 1”. Ou Ru. Zhane CS, Pete Saz Kopsidas 0, Linnane AWS. Naelev Pz ‘Alfred Hospital, 2Monash University, 3Centre for Molecular Biology and Medicine. Melbourne. Background: Previous studies in our laboratory have revealed an age-related decrease in myocardial contractility evident after ischaemia/reperfusion injury. Potential molecular changes underlying this dysfunction include an increased abundance of mitochondrial DNA (mtDNA) mutations such as the mtDNA4977 deletion or a decrease in the copy number of mtDNA genomes. MtDNA mutations may cause energetic and membrane perturbations which may predispose to arrhythmias after cardiac surgery. Aims: (1) To determine mtDNA4977 abundance and mtDNA copy number in right atria1 human heart samples (2) To correlate mtDNA changes with postischaemic myocardial contractility.(3) To correlate mtDNA4977 deletion with postperative atria1 fibrillation. Methodology: Right atria1 strips obtained from patients at operation were subjected to ischaemia/reperfusion stress and contractility measured. DNA extractions were then performed and polymerase chain reaction was used to measure mtDNA4977 abundance and mtDNA copy number per nucleus. Skeletal muscle samples were used for comparison of mtDNA copy number. Postoperative arrhythmias were recorded in the same patients. Results: A novel technique was developed to measure copy number. In the myocardial samples although small (approximately 0.2%) the abundance of mtDNA4977 increased with age (p
GENETIC AND HORMONAL INFLUENCES ON ANDROGEN RECEPTOR EXPRESSION IN HUMAN LEUKOCYTES - A POTENTIAL PROATHEROGENIC MECHANISM IN MEN. M Sader*. A Death. K McGrath, D Handelsman. D Celermaier. Departments of Cardiology, Royal Prince Alfred Hospital; ANZAC Research Institute; Medicine, University of Sydney; and Heart Research Institute, Sydney, Australia. In general, men develop earlier and more severe atherosclerosis than women. We demonstrated that male donor macrophages express significantly more androgen receptor (AR) mRNA than cells from females and that this is associated with enhanced lipid loading by the male macrophages. It is unknown, however, whether enhanced AR mRNA in male leukocytes is due to genetic or hormonal (high ambient testosterone) factors. We therefore studied the influence of hormonal conditions on AR mRNA levels in leukocytes from genetic males and females. mRNA was extracted from whole blood of 6 female to male transsexuals (F2M, age 4Ot9 years) and 6 age-matched male (age 36+9 years) and female controls (age 35+10 years). Samples were also taken from 2 men on androgendeprivation therapy (age Sl?lOyears), 2 age-matched males (age 79+6 years) and 2 hypogonadal males (age 48+10 years) on androgen replacement therapy, at trough and peak serum testosterone. Relative differences in AR expression were assessed by reverse transcription-PCR. Serum testosterone levels in F2M (11+5 nM) were significantly higher than in female controls (1.5+9 nM, p
49th Annual

Scientific

Meeting

of CSANZ

A99

IMPROVEMENT OF FIBRINOLYTIC POTENTIAL WITH TREATMENT OF PERIODONTITIS. G.H. Tofler’. B. Tavlor, S. Philcox, H. Carev. A. Kull. C. Ward. M-C Morel-Konn. Cardiology Department, Royal North Shore Hospital, St Leonards, NSW. Although the association between periodontal disease and cardiovascular risk has been increasingly recognised, it remains uncertain whether there is a causal relationship, Since thrombosis plays a key role in acute coronary syndromes, we investigated the link between haemostatic risk factors and periodontal disease using an intervention model. We studied 25 patients (average age 56.8 years, 60% male) who presented to the United Dental Hospital with advanced periodontitis such that full clearance was recommended. All patients consented to the study. Tests were carried out at 3 timepoints (1) initial presentation, prior to treatment of any acute symptoms; (2) l-2 weeks later when the chronic inflammation of the periodontitis remained untreated; (3) 12 weeks after completion of full clearance. Blood samples were collected in the morning to minimise effects of circadian rhythm. Plasminogen activator inhibitor (PAI-I), tissue plasminogen activator antigen (tPA), Fibrinogen (Clauss) and C-Reactive Protein were measured. Results: Following treatment of the chronic inflammation (between timepoints 2 and 3), there was a 25% reduction in l’AI-1 level (22.3k10.6 versus 16.7+9.6 rig/ml, p=O.O09). There was also a trend to a reduced tPA antigen level (8.1+3.2 versus 7.2k3.1 rig/ml, p
ANDROGENS ENHANCE ENDOTHELIAL VASCULAR CELL ADHESION MOLECULE-l (VCAM-1) EXPRESSION VIA AN ANDROGEN RECEPTOR INDEPENDENT PATHWAY. KCY McGrath. MA Sad&+. DT Handelsman. DS Celermajer. AK Death. Department of Medicine, University of Sydney; ANZAC Research Institute; Heart Research Institute, Sydney, Australia. The marked gender difference in incidence and severity of cardiovascular disease is usually attributed to estrogen’s protective effects. We recently demonstrated that a key early event in atherosclerosis, the binding of monocytes to the endothelium, is enhanced by a non-aromatisable androgen, dihydrotestosterone (DHT), via increased cellular expression of an important cellular adhesion molecule, VCAM-1. We now demonstrate that DHT mediates its effects on VCAM-1 expression at the promoter level via NF-rB activation, rather than in a classical androgen receptor (AR) mediated pathway. Luciferase reporter assays demonstrated specific DHT stimulation of VCAM-1 promoter activity by 130t9% (p
Al(K)

49th Annual

Scientific

Meeting

of CSANZ

Heart,

COMPARISON OF EFFECTS OF PRAVASTATIN AND COMBINED HORMONE REPLACEMENT THERAPY ON PLATELET AND SOLUBLE P-SELECTIN. R.E. Centre for Heart and Chest Research, Department of Medicine, Monash Medical Centre and Monash University, and Jean Hailes Centre, Clayton, Victoria Soluble p-s&&in (SPS) is a cell-surface adhesion molecule which can be measured in plasma and which, in a recent prospective study, was found to be an independent risk factor of cardiovascular events in apparently healthy women. Although p-selectin is present in platelets and endothelial cells, the major source of SPS remains unclear and there is little information about factors which modify SPS levels. To address these questions we measured SPS and surface expression of platelet p-selectin (PPS), which increases during platelet activation, in a randomised, double-blind study, performed in 43 postmenopausal women with hypercholesterolaemia treated with pravastatin 20mg (n=21) or low-dose combined HRT (lmg &radio1 + 0.5mg norethisterone; n=22). PI’S was measured by flow cytometry and SPS was measured by ELISA at baseline and 6 months. There were no baseline differences in age, BMI or lipids between the two groups, but there was a trend to a higher baseline SPS level in the HRT group (p=O.O7). No relationship was evident between PPS and SPS at baseline or between baseline lipid levels and either PPS or SPS. Marker PF5 % SFS (ng/mL)

Treatment HRT PCWClStatin HRT Pravastatin

Baseline 6.7 + 2.9% (SD) 5.2 + 3.3% 50.3 * 14.5 42.9 + 11.5

6 months 8.5 t; 4.0% 4.1 + 2.9% 36.1 + 6.7 33.7 r 6.9

P 0.06 0.04 <0.0001
After adjusting for baseline differences, HRT and pravastatin produced similar reductions in SPS but had divergent effects on PPS, with pravastatin reducing and HRT increasing expression of PI’S (p
COAGULATION GENE POLYMORPHISMS/MUTATIONS OCCUR MORE FREQUENTLY IN PATIENTS WITHOUT ANGIOGRAPHIC STENOSES FOLLOWING MYOCARDIAL INFARCTION. J.K. French*, daer. N.S. Van e W t P..B tt J.Po c o n D.Sz Department of Haematology, Auckland Hospital, Department of Cardiology, Green Lane Hospital, Department of Molecular Medicine, University of Auckland, Auckland, New Zealand and Ohio State University, Columbus Ohio, USA. While the frequencies of Factor V Leiden and prothrombin variant G20210A frequencies are not increased in unselected patients with acute myocardial infarction (MI), we and other groups have reported an increased frequency of these two mutations/polymorphisms in young patients who had normal coronary arteries at angiography following MI. To determine whether the frequencies of mutations/polymorphisms in other genes potentially pro-thrombotic were also increased, we studied I’CR-amplified DNA extracted from blood samples of 60 patients who had normal coronary arteries (no stenosis >50%), and 211 patients with at least one stenosis >50%, at angiography one month following MI; patients were stratified by age (~50 v 250 years). Mutations/polymorphisms examined included methyl tetrahydrofolate reductase 677 C/T, platelet PlAl/A2, P-fibrinogen 448 G/A, plasminogen activator inhibitor-1(4G/5G), angiotensin II type 1 receptor (A/C), haemochromatosis gene (G/A), nitric oxide synthase (NOS) (3 forms eNOS, eNOS3, eNOS4), p22 phox of NADPH oxidase, and angiotensin converting enzyme I/D polymorphism. The frequency of the A allele of P-fibrinogen was increased in patients without stenosis compared to patients with 21 stenosis irrespective of age (c2=4.0; P=O.O4) and there was a trend towards increased frequency in those aged ~50 years (I’=O.O58). However there was not an increased frequency of any of the other gene mutations/polymorphisms. Of patients with no stenosis following MI, 55% had at least one of factor V Leiden, prothrombin variant G20210A and p-fibrinogen 448 A allele, whereas 32% of patients with at least 1 stenosis after MI, had at least one of these possible genetic risk factors for thrombosis (P=O.OOl); in patients aged ~50 years, the respective frequencies were 59% and 31% (P=O.O02). We conclude that compared to patients with angiographic stenoses, factor V L&den, prothrombin variant G20210A and p-fibrinogen (448A) polymorphisms are increased in frequency in patients with angiographically normal coronary arteries following MI.

Lung

and Circulation

SPINAL CORD STIMULATION SIGNIFICANTLY TORY ANGINA PECTORIS. ;Allada*. R.1. Ecclestone. P.S. Macdonald. St. Vincent’s Hospital,

IMPROVES Sydney,

2001; 10

REFRAC-

Australia.

A small cohort of patients have resistant angina pectoris despite revascularisation: coronary artery bypass grafts (CABGs), percutaneous coronary angioplasty (PTCA), stenting and transmyocardial laser revascularisation (TMLR). Spinal cord stimulation (SCS) with an epidural implanted system may alleviate symptoms. We report our preliminary experience. SCS was performed in 6 male patients with average age 57.5i7.1 years (48-67 years) and NYHA Class III-IV angina, between March and December 2000. Median follow up is 6 months (range 2-10 months). All had normal left ventricular ejection fraction (54+9.5%, range 40-67%). All had previously undergone revascularisation; 4 patients had CABGs once, (1 also had subsequent PTCA and stenting), 1 patient had CABGs twice and 1 patient had CABGs three times. Four had previously undergone TMLR with return of angina at 4, 4, 6, and 36 months respectively post-laser procedure. All had intractable angina despite maximal medical therapy. Three patients required narcotics for angina. Five patients had been referred for cardiac transplantation. There were no complications associated with the procedure. 1 patient developed a pulmonary embolism 3 months post procedure. Angina class fell from NYHA Class IV to Class I (1 patient) and Class II (4 patients). No effect on angina was seen in 1 patient since adequate positioning of the lead to cover the distribution of angina was not achieved. Overall, 5/6 (83%) of patients have experienced a 64% mean reduction in frequency of angina, 84% mean reduction of angina at rest, 63% mean reduction in angina with light activity and 15% mean reduction in angina with moderate activity. Six minute walk test improved by 7% (baseline average 417m) and specific activity scale improved from a baseline of Level IV to II at latest follow-up. In conclusion, preliminary results with short term follow up, demonstrate SC’S to be an effective and safe therapy for an otherwise very resistant group of patients with angina.

ACUTE AND CHRONIC TEA CONSUMPTION REVERSES ENDOTHELIAL DYSFUNCTION IN PATIENTS WITH CORONARY ARTERY DISEASE. ST,. * .F. K ane B. Frei, T.A. Vita. Boston University School of Medicine, Boston, MA, USA. Background: Epidemiological studies suggest that tea consumption is associated with decreased risk of cardiovascular events, but the mechanisms of benefit remain undefined. Endothelial dysfunction has been associated with coronary artery disease and increased &dative stress. Some antioxidants have been shown to reverse endothelial dysfunction, and tea contains antioxidant flavonoids. Methods and Results: To test the hypothesis that tea consumption will reverse endothelial dysfunction, we randomized 66 patients with proven coronary artery disease to consume black tea and water in a cross-over design. Acute effects were examined two hours after consumption of 450 ml of black tea or water. Chronic effects were examined after consumption of 900 ml of tea or water daily for four weeks. Endothelium-dependent flow-mediated dilation and endothelium-independent nitroglycerin-mediated dilation of the bra&al artery were examined at baseline and after each intervention using high-resolution vascular ultrasound. A total of 50 patients completed the protocol and had technically suitable ultrasound measurements. Both acute and chronic tea consumption improved flow-mediated dilation of the brachial artery, while consumption of water had no effect (P
Heart,

Lung

and Circulation

49th Annual

2001; 10

EFFECT OF ACUTE AND CHRONIC TEA CONSUMPTION ON PLATELET AGGREGATION IN PATIENTS WITH CORONARY ARTERY DISEASE. 3.1. Duffv*. I.A. Vita. M. Holbrook. l? Swerdloff. I.F. Keanev, Ir. Boston University School of Medicine, Boston, MA, USA. Background: Epidemiological studies suggest that tea consumption is associated with decreased risk of cardiovascular events, but the mechanisms of benefit remain undefined. Platelet aggregation is a precipitating event in acute coronary syndromes and is associated with increased oxidative stress. Some antioxidants have been shown to decrease platelet aggregation, and tea contains antioxidant flavonoids. Methods and Results: To test the hypothesis that tea consumption will decrease platelet aggregation, we randomized 66 patients with proven coronary artery disease to either 450 ml of black tea or water consumed acutely, followed by 900 ml of tea or water daily for 4 weeks in a crossover design. The rate and extent of ex vivo platelet aggregation in platelet-rich plasma was assessed in response to adenosine 5’-diphosphate (1 10 pmol/l) and thrombin receptor activating peptide (5 - 50 pmol/l) at baseline, 2 hours and 4 weeks after beverage consumption. A total of 49 patients, aged 55.1k9.3 years (mean * standard deviation), completed the protocol and had platelet aggregation studies at all 6 time points. We observed dose-dependent platelet aggregation in response to each agonist, and neither relation was altered by acute or chronic tea consumption. These dose-response relations were highly reproducible as the responses before and after either acute or chronic water were virtually identical. Plasma flavonoids increased with acute and chronic tea consumption, indicating adequate absorption of tea flavonoids. Conclusions: These results demonstrate that acute and chronic tea consumption does not affect ex viva platelet aggregation in patients with coronary artery disease. These findings suggest that an effect of tea flavonoids on platelet aggregation is unlikely to be the explanation for cardiovascular event risk reduction noted in epidemiological studies.

EFFECTS OF DIABETES MELLITUS AND ASSOCIATED GLYCAEMIC CONTROL ON PLATELET FUNCTION IN UNSTABLE ANGINA PECTORIS. M.I. Worthlev”. A.S.Holmes. Y.Y. Chirkov. I.D. Horowitz. Cardiology Unit, North Western Adelaide Health Service, University of Adelaide, S.A. Diabetic patients are known to have an increase mortality with unstable angina pectoris (UAI?) when compared to non-diabetics. Recently, admission blood sugar levels (BSL) and glycosylated haemoglobin concentrations (HbAlC) have been shown to be independent predictors of mortality in diabetic patients presenting with an acute myocardial infarction. Although a number of hypotheses have been postulated to explain this increase in mortality, no consensus on the mechanisms behind this observation have been reached to date. We have previously shown that platelets from patients with UAP are hyporesponsive to the anti-aggregatory effects of nitric oxide (NO) donors such as sodium nitroprusside (SNP). We now tested the following hypotheses in consecutive patients admitted with UAP +/- type II diabetes mellitus. 1) That diabetes modulates platelet reactivity to NO among UAP patients. 2) That glycaemic control (as measured by admission HbAlC and/or admission BSL) is independent of platelet reactivity among diabetic patients admitted with UAP. Methods: 25 type II diabetic patients with UAP and 26 non-diabetic patients with UAP were enrolled into the study. On admission, blood was taken for plasma glucose, HbAlC levels and platelet aggregometry studies. The extent of ADP-induced platelet aggregation (ImM, whole blood impedance aggregometry ) and the degree of inhibition of aggregation by SNP (lOpM)(% inhibition of control) was examined. Results: Aggregability to ADP did not differ significantly between diabetic and non diabetic patients. The extent of hyporesponsiveness to NO did not vary significantly between diabetic (SNP response 42%+/- 3.5 SEM) and nondiabetic ( 30% +/- 5.3) patients, although both were resistant relative to 30normal subjects (65.3% +/-4.0). With the diabetic group, SNP response tended to be diminished with increasing HbAlC (r= -0.3, p=O.15) and with increasing admission BSL (r= -0.4, p= 0.045). The diabetic group also tended to have an increased total aggregability with increased HbAlC (r= -0.37, p= 0.07) and with increasing admission BSL (r= -0.41, p= 0.04). Among diabetic patients with UAP, admission BSLwas 12.6 +/- 1.1 (range 5.1 - 31.7). Conclusions: 1) Among patients with UAP, diabetes per se does not appear to be associated with incremental platelet resistance to NO. 2) Among diabetic patients with UAP, admission BSL is a weak predictor of platelet NO resistance and aggregability

Scientific

Meeting

of CSANZ

AlO1

ARE INITIAL ECG FINDINGS MORE IMPORTANT THAN TIME TO TREATMENT OR 90 MINUTE INFARCT RELATED ARTERY FLOW IN PREDICTING MYOCARDIAL SALVAGE WITH THROMBOLYTIC THERAPY? CK [email protected]+, HD White for the HERO-l investieators. Cardiology, Green Lane Hospital, Auckland, New Zealand Patients with Q waves and T inversion on the initial electrocardiogram are generally at a later stage of the infarction process than those without these changes. Electrocardiographic algorithms to calculate potential and final infarct size allow the calculation of myocardium salvaged with therapy. Myocardial salvage after thrombolytic therapy was measured in 146 patients with acute myocardial infarction undergoing angiography at a median of 91 minutes. The relationship between myocardial salvage and the presenting electrocardiographic parameters including Q waves, T wave inversion, quantitative ST segment changes, and the initial QRS score (QRSi), were examined together with the 90 minute infarct-related artery TIMI flow grade and collateral grade, and clinical parameters including the hemodynamics on presentation, age, and time to therapy. Parameters that correlated with myocardial salvage included QRSi (r = -0.56, P
SIGNIFICANT REDUCTION OF THROMBOLYTIC THERAPY ‘DOOR TO NEEDLE TIME’ FOLLOWING A PROGRAMME OF PROSPECTIVE DATA COLLECTION AND AN AUDIT FEEDBACK LOOP. CI Ellis*. PG Tones. ANW McClelland. W Benjamin. R Ronaldson. 1 Bebbington, D Gasson, G Gamble. Depts of Medicine and Emergency Medicine, Auckland Hospital, Auckland. To save lives, minimal delay should occur in the ‘door to needle’ time (DTNT) when patients (pts) with a myocardial infarction (MI) receive thrombolytic therapy (TT). The ‘ideal’ target DTNT is said to be < 30 minutes (mins). Other authorities suggest < M) mins for all pts. We retrospectively reviewed the baseline DTNT for pts, and then prospectively institited a programme designed to improve on this time. Over 18 months, 171 pts (mean age 61 [IQR 52-701 years, 68% male) received ‘IT in the ED, and were admitted to CCU. The median DTNT was 49.5 mins (IQR 30-73 mins), with 27% pts being treated within 30 mins, 65% within 60 mins and 81% within 90 mins. For 35 pts with DTNT > 90 mins, the median time was 137 mins (IQR 106-210 mins). From l/12/00 a DTNT programme was initiated, with medical and nursing staff in ED and CCU being expected to prospectively complete and sign an audit form, based on data required for the Australian ‘National Audit of Thrombolysis’ (NATDAT) programme. CCU and ED nursing and medical staff ensured complete data collection by reviewing all audit forms, and correlating with the comprehensive CCU database that records all CCU admissions (1700 pts/year). From l/12/00 to 31/l/01, 18 pts (mean age 64 [IQR 59-721 years, 67% male) received ‘IT in ED, with a median DTNT of 30 mins (IQR 28-68 mins). This represents a significant improvement in median DTNT from the retrospective baseline audit (49.5 v 30 min, Wilcoxon p=O.O20). Nonetheless, 50% of pts still have a median DTNT of > 30 mins, and

22% > 60 mins.

Hence,

further

along with ongoing audit of Conclusion: A simple and mechanism can significantly requiring TT. This tool could

feedback

mechanisms

are being

instituted,

the DTNT. reliable prospective audit with a feedback improve the DTNT for pts presenting with be widely used in all hospitals.

loop a MI

AlO2

49th Annual Scientific Meeting of CSANZ

Heart, Lung and Circulation

WHAT IS A MYOCARDIAL INFARCTION?: PROSPECTIVE ANALYSIS OF THE DIAGNOSTIC AND PROGNOSTIC IMPACT OF ADDING TROPONINS TO THE DEFINITION. m. Elliott*, R. Newman, D. Brieper, S. Goodman, for the GRACE Investigators. Dept Cardiology, Christchurch Hospital, New Zealand Cardiac troponin T and I levels are now included in the definition of myocardial infarction (MI). Troponins (Tn) may rise in the absence of significant rise in creatinine kinase (CK) levels and are associated with a worse prognosis in retrospective analyses within clinical trials. We have assessed the effect of the new Tn definition on the incidence of MI, and evaluated the prognosis of Tn positive patients in our registry. The Global Registry of Acute Coronary Events Registry (GRACE) is a prospective, multinational, observational study of patients hospitalized with acute coronary syndromes (ACS) in 94 centres in 15 countries including Australia and New Zealand. Peak standard (CK, CK-MB) and new TnI or TnT cardiac markers were all available in 3,420 of 8,213 ACS patients enrolled from April 1999 to June 2000. The addition of isolated troponin positive (Tn+) patients resulted in a further 15%, 26%, and 9% increase in the rate of myocardial infarction diagnosis beyond those defined by either CK supper limit of normal (ULN), CK >2 times (2x) ULN, or CK-MB >ULN, respectively. The odds ratio (OR) for in-hospital mortality was significantly* higher in Tn+ patients (see Table). CK<=zx N (“‘o) OR (95% CI) for in-hospital death

ULN, Tn1,285 (38%) 1

CK<=zx ULN, Tn+ 900 (26%) 3.0' (1.6.5.7)

CK>ZX ULN, Tn124 (4%) 2.1 (0.6, 7.4)

CK>ZX ULN, Tnc 1,111 (32%) 5.8' (3.3,lO.l)

The use of troponins in addition to CK may lead to a 25% increase in the number ACS patients meeting the criteria for the diagnosis of myocardial infarction. Furthermore, this group of patients experiences a 3-fold increase in short-term mortality compared with Tn- patients and a 1.5-fold increase compared to the traditional cardiac enzyme definition.

THE RELATIONSHIP BETWEEN LEFT VENTRICULAR INDICES OF SPHERICITY AND LATE SURVIVAL AmER MYOCARDIAL INFARCTION. S.P. [email protected]: T.K. French; A. Lvdon; N.G. Ashton. H.D. White. Green Lane Hospital, Auckland, New Zealand Following myocardial infarction (Ml) left ventricular (LV) ejection fraction and end systolic volume are major determinants of late survival. Though LV shape influences exercise capacity after Ml, there are few data about its quantification and influence on late survival. To determine the influence of LV shape on late survival, at a median of 6.5 years after MI, we studied 825 patients presenting with ST segment elevation within 4 hours of symptom-onset who underwent biplane ventriculography at 3 weeks. LV spheric&y indices (SI) were defined as: SIl - ratio of minor axis to major axis, S12 ratio of average of minor axis to major axis, S13 - ratio of planar LV area to perimeter, S14 - ratio of measured volume to volume of a sphere with the same long axis and S15 - ratio of measured volume to volume of a sphere with the same surface area. SIs were calculated separately for single and bi-plane measurements and analysed blinded to treatment and outcome. Univariate SI predictors of late survival were SIlx* =27.0; S12x2 =24.8; S13x2 =20.3; S14x2 =24.6; S15xz =8.8 (all P
2001; 10

BIOLOGIC RESPONSE TO THE HELEX=.” SEPTAL OCCLUDER IMPLANTATION IN THE CANINE HEART. GK Lane*. *N Macri, JF Rhodes. CI&sia. LR Prietoi+P Sawyer, *M Manninn. fD Anderson, *m Cutrieht. YE-EMZahn and LA Latson. The Cleveland Clinic Foundation, Cleveland, Ohio, USA; *W.L. Gore & Associates Inc, Flagstaff, Arizona, USA; ‘Miami Children’s Hospital, Miami, Florida, USA. Background: The HELEXTM septal occluder device is a nitinol framed double circular disc with ultra-thin bonded ePTFE, which has recently been used in humans for transcatheter secundum atria1 septal defect closure. We report the preliminary data on the biologic response to implantation of this device in the canine heart. Methods: Histologic data from 30 animals enrolled in non-randomised prospective studies conducted at W.L. Gore & Associates lnc and The Cleveland Clinic Foundation were analysed. Animals had either a surgically created or a percutaneously created atria1 septal defect and immediate implantation (Group 1: n = 25) or delayed implantation of a HELEXTM device 14 days following a percutaneously created atria1 septal defect (Group 2: n = 5). Post implantation, animals were maintained on Slmg of aspirin daily. Animals were sacrificed at differing intervals as outlined in Table 1 and all devices were examined grossly within the atria and then removed en bloc with the atria1 septum. Multiple sections of the device and surrounding atria1 septum were obtained and assessed for fibrous connective tissue and endothelial like cells. A p value co.05 was considered statistically significant. Table 1. Time to Sacrifice (days) Group 1. Groun 2.

2 4

3

14 2 2

3045 5

89 1

180 7

365 5

737 1

Results: Fibrous connective tissue completely covered the left atria1 component of the HELEXTM device by 45 days post implantation in 5/5 (100%) subjects with coverage of the entire HELEX TM device in 6/7 (85%) subjects by 6 months post implantation. One device had complete coverage of the right atria1 side of the device, with extensive coverage of the left atria1 side at 6 months. Of the devices with an implantation time greater than 6 months, 6/6 (100%) were fully covered with fibrous connective tissue. There was a trend for greater fibrous connective tissue and endothelial like cell coverage of devices which had delayed implantation compared to immediate device implantation. When the extent of coverage of the device with fibrous connective tissue and “endothelial like cells” were analysed against the length of time post implantation, there was also a trend for coverage to increase with time. There was no macroscopic or microscopic evidence of distal organ thromboembolism in any of the animals studied at any time interval post implantation. Conclusions: The process of endothelialisation of newly implanted HELEX TM devices appears to be progressive with initial fibrous connective tissue coverage followed by “endothelial like cells”. There is near complete coverage of the device with fibrous connective tissue by 30-45 days post implantation with no evidence of distal thromboembolism. The immediate deployment of the HELEXTM device in acutely created atria1 septal defects appears to be associated with a delay in endovascular coverage of the implanted device. These data support the need for further research into the process of endothelialisation of the HELEXTM and other ASD devices.

Heart,

Lung

and

Circulation

2001;

49th

10

CATHETER ABLATION OF TACHYARRHYTHMIAS RECENT RESULTS FROM AUCKLAND. l.R.Skinner*. Green Lane, Auckland.

IN CHILDREN: M. Hood, W. Smith.

Between June 1998 and December 2000,89 children (~17 years) were referred for electrophysiology study with a view to radiofrequency ablation (RFA) of tachyarrhythmias (84 supraventricular (SVT) and 5 ventricular (VT). This abstract reviews this experience. All studies were performed under general anaesthesia. Standard computerised electrophysiology equipment was used. Previously documented arrhythmias could not be induced in 7 (8%) (4 VT and 3 SVT). RFA was therefore attempted in 82 patients (pts.) (81 SVT, 1 VT) of whom 11 pts (13%) had congenital heart disease (CHD). Median age was 12 years (range 2.9-16.9). SVTs were due to accessory pathways (AI’s) in 54 (65%), including one Mahaim fibre, AV nodal reentry (AVNRT) in 25 (30%) and atria1 tachycardia in 4 (5%). (One pt. had 2 Al’s and AVNRT). Successful RFA was achieved in 74/82 pts. (90%). Median procedure time was 128 minutes (range 55-360), and median flouroscopy time 18 minutes (6-69). There were no deaths, atrioventricular block or other serious complications. With a median follow up of 18 months (l-54), tachycardia or delta wave recurred in 7/74 (9%). 5 of these 7 have thus far been re-ablated successfully. The 8 initial failures related to CHD in 3 pts; (Ebstein’s anomaly, tetralogy of Fallot with left SVC to coronary sinus, and incisional tachycardia in tricuspid atresia) and to proximity of the substrate to the His bundle in 5 (3 parahisian APs, 1 AVNRT, 1 ectopic atria1 focus). 3 of these 8 underwent redo RFA, with success in 2. Overall current freedom from arrhythmia 75/82 (91%). Conclusion: RFA can be done safely and with acceptable success rates and flouroscopy times in children, though general anaesthesia tends to prevent induction of tachyarrhythmias, especially VT. The most challenging groups are those with coexisting CHD and those with substrates close to the His bundle.

Annual

Scientific

Meeting

of CSANZ

A103

ATRIAL SEPTAL DEFECT CLOSURE WITH THE HELEXTM SEPTAL OCCLUDER DEVICE: THE FDA PHASE I FEASIBILITY TRIAL. JF Rhodes, *NC Dobrolet. GK Lane*. CI Mesia. AH Toth. *EM Zahn. and LA w The Cleveland Clinic Foundation, Cleveland, Ohio, USA and *Miami Children’s Hospital, Miami, Florida, USA. Background: The HelexTM septal occluder device is an ePTFE covered nitinol double circular disk device for transcatheter atria1 septal defect (ASD) closure. We report preliminary data on device safety and performance. Methods: Between 4/00+12/00, all appropriate patients with secondurn-ASD in two centres were enrolled in a prospective, non-randomised FDA phase-1 feasibility trial. Procedures were performed using general anaesthesia with transoesophageal echocardiography guidance. Procedural success was defined as accurate placement of a device. Chest X-ray and transthoracic echocardiography were performed 24hrs, lmth, Gmths and lyr following deployment. Results: Thirty-eight patients, median age 1Oyrs (range 0.4+55yrs), underwent 40 catheterisations. Static balloon-stretched ASD diameter was 7.1+26mm (17e4.4). Device/balloon waist ratio was 1.3+4.2 (1.8iO.5). The procedure was successful in 34/40 catheterisations with 3/6 failures due to unavailability of the largest (35mm) device. One of these patients underwent closure with a 4Omm CardioSeaP at initial catheterisation and 2 returned for closure with a 35mm-HelexTM device. The remaining 3 procedural failures were closed surgically. In all procedures, the device design allowed repositioning for optimal placement prior to release. There were 7 procedurerelated minor adverse events with device embolisation (uneventful retrieval) in 2 patients, transient arrhythmia in 3 patients and transient ST depression in 2 patients. Median fluoroscopy time was 23 minutes (including 4 patients with additional interventional procedures). Chest X-ray and transthoracic echocardiography at 24hrs demonstrated a well-seated device in all patients and trivial/small residual leaks in 23/34(68%) of patients. Trivial/small residual leaks were present in 15/27(55%) of patients with lmth data and l/6(17%) of patients with 6mth follow-up. Conclusion: These data indicate that the H&P device is safe for secundum ASD closure. The ability to easily reposition/retrieve this device may be an advantage. No patient has a significant residual leak and the incidence of trivial/small leaks decreased during follow-up.

SIMPLE TRANSCATHETER CLOSURE OF ATRIAL SEI’TAL DEFECTS NOT SO SIMPLE? l?G. Biomstad*. 8. Smevik. E. Fosse. Paediatric Clinic and The Interventional Centre, Rikshospitalet, The National Hospital, Oslo, Norway

AUTOMATIC CONSTRUCTION OF 3D AORTIC SHAPE FROM MRI FLOW (PHASE CONTRAST) IMAGES. KR Movie*. GD Mallinson. AA Youne. CT Occleshaw. TL Gentles, BR Cowan. Cardiac MRl Research Group, University of Auckland, Auckland.

Closure of atria1 septal defects with the Amplatzer device has become a standard therapy in many centres. It has been regarded as a simple procedure with few failures and a low complication rate. Our institution started already in 1996 with the technique after prior animal training. During the first 44 procedures there were four patients intended to treat who were left with the defect without any attempts to close: each one with azygos continuation and anomalous pulmonary vein, two with defects of 34 and 38 mm respectively. In another two closure was attempted: in one a 30 mm device could not achieve a stable position and was removed before release. In a second patient a 26 mm device was implanted with difficulties, thought to be in stable position, but turned 90’ after release with a big residual shunt. This device was catched with a snare and removed. During the initial team leader’s sabbatical year, twelve further patients were taken to the lab for defect closure by a less experienced team. After initial success in 8 with defects ranging from 17-26 mm the following four created problems. 2/12 (17%) had to be taken to emergency surgery: one patient had the device erroneously unscrewed with just a little bit of the device still in the introducer sheath. The procedure was immediately converted into open heart surgery in the lab where such facilities are available. Another was operated later the same day because of embolisation to the right atrium of a device straddling the septum. In two further cases the defects could not be closed and the device was removed. We conclude that there still are enough pitfalls in this “simple” procedure to demand meticulous techniques both before and during the procedure, and the use of the most experienced team available.

MRl is capable of determining blood flow velocity non-invasively with a high degree of spatial and temporal accuracy. The aim of this study was to test the hypothesis that the 3-dimensional shape of the aorta could be automatically reconstructed from phase contrast (PC) MRl data. Methods: Five parallel para-sagiltal MRl slices (Siemens Vision 1.5 T, 6mm thickness) were acquired through the aortic arch in 15 young adults who had undergone coarctation repair in childhood. Each slice was scanned three times, one for each of the 3 velocity directions and both the anatomical (intensity) images and flow (PC) images stored on CDROM. In order to determine which pixels represented flow and were therefom inside the aorta, the intensity/ velocity ratio was calculated for each pixel. Pixels with a ratio above a critical threshold identified them as being inside the aorta. Further improvements were made using additional information contained in later scans in the cardiac cycle. The resulting flow maps were then registered in 3D and scanned for points on the edge of the aorta which were then used to construct a model representing the surface of the vessel. Results: The figure to the left shows an example of the reconstructed surface of an aorta with a residual stenosis in the proximal aspect of the descending aorta (arrowed). Conclusion: In addition to the detailed velocity information provided by MRI PC imaging, automatic reconstructions of the three-dimensional shape of the aorta are possible. These surfaces can be used to assist with interpretation of anatomy, or to define the regions of the PC images suitable for detailed flow analysis.

AlO4

49th Annual

Scientific

Meeting

of CSANZ

Heart,

VALUE OF ADDING LOW LEVEL EXERCISE TO ADENOSINE STRESS FOR MYOCARDIAL PERFUSION SCINTIGRAPHY WITH 99mTc SESTAMIBI. LET Thomson*. MT Lincoln. B Coutinho. V Bush. KC Allman. Nuclear Cardiology, Nuclear Medicine Department, Concord Hospital, Sydney Objectives: Vasodilator stress can be accompanied by unpleasant patient side effects and may also adversely affect myocardial perfusion image quality by increasing splanchnic tracer uptake. We investigated if these factors could be improved by adding low-level exercise during intravenous adenosine vasodilator stress. Methods: 66 consecutive eligible patients (age 65 f 10 yrs, 35 males) presenting for %Tc sestamibi (MIBI) SPECT received adenosine 14Omcg/kg/min for 4minutes either combined with (EX+) or without (EX-) treadmill exercise. Symptoms during adenosine infusion (headache, breatblessness, nausea, chest pain, flushing) were recorded. Cardiac image quality was assessed by a semiquantitative visual score (from 0 = no splancbnic activity to 4 = oninterpretable image) by 2 observers (agreement: r=0.85). Region of interest analysis of heart:liver and heartleft upper abdominal quadrant (LUQ) uptake of MIBI was also performed. Data were analysed by Mann Whitney U and ~2 tests. Results: Both groups were well matched for age, sex, coronary risk factors and resting heart rate/blood pressure. The EX+ group had superior image quality scores and higher ratios of cardiac to splanchnic MlBI uptake. The EX+ group were less likely to report headache during adenosine infusion (3 vs 12, p=O.O06) and tended to require less repeat stress imaging for excessive splanchnic activity (5 vs 11, p=O.O8). In the EX+ group exercise time was 4.5 minutes, workload achieved was 3.0 METS and peak heart rate was higher (105 f 2.9 vs 91 r 3.8bpm, p=O.O004). Parameter dSBl’(mmHg)

Ex+ bnean * San)

EX- (mean * sem)

P

5.7 + 3.4 -2.2 + 1.3 1.0 r 0.16

-11 f 3.7 2.7 k 1.6 1.7 r 0.2

0.003 0.01 0.01

Heart:LUQ ratio Mean &/pixel

1.3 t 0.07

1.0 * 0.07

0.007

Heart:Liver ratio Mean &/pixel

0.7 + 0.06

0.6 + 0.08

0.02

dDBP Visual Score

Conclusion: Low level exercise combined with adenosine pharmacologic stress successfully reduces patient side effects and improves SPECT image quality in stress myocardial perfusion scintigraphy with 99mTc sestamibi.

DETECTION OF POTENTIAL MYOCARDIAL ISCHAEMIA IN HIGH RISK PATIENTS WITH CHRONIC RENAL FAILURE : IS CORONARY ANGIOGRAPHY NECESSARY? M.I. Worthlev’. S.A. Uneer, T.H. Matbew, G.R. Russ. I.D. Horowitz. Cardiology and Nepbrology Units, North Western Adelaide Health Service, University of Adelaide, S.A. Patients with chronic renal failure (CRF) have a high prevalence of coronary artery disease (CAD) ; acute ischaemic events account for approximately 50% of peri-renal transplant deaths. In such patients myocardial ischaemia may be minimally symptomatic. As previous studies suggest that stress imaging (generally performed with pharmacological stress in previous studies) is poorly predictive of coronary anatomy, coronary angiography (CA) has become a routine component of pre-renal transplant screening (PRTS). In high risk patients undergoing PRTS, we tested the hypothesis that stress myocardial perfusion imaging results are predictive of the presence/absence of haemodynamically significant coronary stenoses. Of 33 patients studied, 5 had angina pectoris, 26 had diabetes, 22 were aboriginal and their age was 49+/- 9 (SD) years. Exercise testing was performed in 21 patients and 12 were stressed via pacing, maximum heart rate achieved was 142 +/- 21. Imaging was performed using Tc99m tetrofosmin (n=31) and Tc99m sestamibi (n=2) and was interpreted by nuclear cardiologists blinded as to the catheterization results. Cardiac catheterization and CA were performed in all patients. The majority of patients had abnormal haemodynamics at rest (PCWP 15 +/2 mmHg) albeit normal systolic function (LVEF 61+/- 19%). SPECT scan result History of angina (~5) No angina (II= 28) Significant CAD on CA(n=lO)

Positive

Negative

4 (80%) 7 (25%) 10 (100%)

1 (20%) 21 (75%) 0 (0%)

The positive and negative predictive accuracies of scanning were 91% (95%CI 59,99%) and 100% (95%CI 85,100%) respectively. The positive and negative predictive values of angina were 80% (95%CI 28,99%) and 79% (95%CI 60,92%) respectively. Three of the ten patients with significant CAD were successfully revascularised (1 PTCA and 2 CABG). Eight of the 33 patients screened have been successfully transplanted with no cardiac complications. Conclusions: 1) In this cohort, only 30% of patients (32% of aboriginal patients) with CRF undergoing PRTS had significant CAD.2) Exercise/pacing scintigraphy provides a highly accurate screening test for significant CAD and should replace routine CA.

Lung

and Circulation

2001; 10

AGE RELATED CHANGES IN MYOCARDIAL RELAXATION USING TAGGED MAGNETIC RESONANCE IMAGING J H C Oxenham*. A A Youne. B R Cowan. RnQuehtv. N Shame University of Auckland, Auckland, New Zealand Background: Magnetic resonance imaging (MRI) with tagging provides novel information regarding the complex, three-dimensional motion of the heart. Localized radio frequency labels specific regions within the myocardium creating a grid pattern, which becomes deformed as the myocardium moves. Analysis of this deformation allows direct measurement of the movement of the myocardium. Methods: Tagged MRl images from two groups of normal individuals were analysed using dedicated computer software. The mean age of the younger group was 24 years (range 20-26 years, n=S) and that of the older group was 65 years (range 60-74 years, n =7); 1 I of the 13 subjects were male. Analysis of tagged images provided values for apical rotation (degrees of clockwise rotation from the onset of systole, viewed from the apex) and circumferential shortening through most of the cardiac cycle. Results: During systole there Apical Rotation were no significant differences (mearard) ,s between the two groups. However, during early diastole E s 10 (time = 150% of end-systole), ._ mean apical rotation persisting E was 6.8 (range 5.1-8.9 ) in-2 the older group, compared with 2 s 2.6 (range 0.3-6.0 ) in the: younger group (p
DOES LOW DOSE BIVALIRUDIN (ANGIOMAXI”) ALLOW EARLY MOBILISATION AND DISCHARGE FOLLOWING PERCUTANEOUS CORONARY INTERVENTION? Jvl.J. Ahernethv*. J.E. Ouian; Wakefield Heart Centre, Wakefield Hospital, Wellington, New Zealand. Bivalirudin is safer and more efficacious than heparin, when used as an anticoagulant in percutaneous coronary interventions (PCI). Bivalirudin has a shorter half-life (25 minutes) than heparin, thus the objective of this audit was to determine whether this would allow for earlier sheath removal, mohilisation and discharge following elective PCI. Patients undergoing elective PC1 were given a low dose holus of hivalirudin (0.5 m&g) after insertion of the arterial sheath. The activated clotting time (ACT) was measured five minutes post bolus and a further bolus given if required to bring the ACT >200 seconds. PC1 was performed in the usual manner. Further ACTS were measured thirty minutes post bolus and prior to sheath removal. The patient started mobilising three hours following successful sheath removal. Ten hours following the PC1 an electrocardiogram (ECG) and rapid Troponin-T were performed. To-date, 30 patients have had low dose bolus bivalirudin, with an average ACT five minutes post holus of 286 seconds. The sheaths were removed an average of 72 minutes post bolus. Twenty-one patients had mobilised pain free at ten hours with a normal Troponin-T and no ECG changes, and could be considered for early discharge. Nine were unsuitable for discharge for the following reasons; 7 patients received GP IIB/IIIA inhibitors, 1 suffered groin complications, and 1 had ECG changes/Troponin-T. There have been no deaths, urgent revascularisations, Q-wave myocardial infarctions or cerebral-vascular accidents. The favourable pharmacokinetics of low dose bolus bivalirudin, allows consideration for early mobilisation and discharge in most patients presenting for elective PCI. The results of the first one hundred patients audited will he presented.

Heart,

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49th Annual

2001; 10

ACUTE PROCEDURAL COMPLICATIONS AND IN-HOSPITAL EVENTS AFTER PERCUTANEOUS CORONARY INTERVENTIONS: EPTIFIBATIDE VS. ABCIXIMAB. A E Aian?. L Grubere. M Castaena. L Satler, K Kent, A Pichard & R Waksman Washington Hospital Center, Washington DC Background: Glycoprotein lIb/IIIa antagonists reduce peri-angioplasty ischemic complications and improve in-hospital outcome in patients undergoing Percutaneous Coronary Interventions (PCI). Prior studies demonstrated favorable results with both eptifibatide and abciximab. The purpose of this study was to assess whether there are any differences in acute procedual complications and in hospital events with the use of these two agents. Methods: A retrospective review of 359 elective PCIs from June 1998 to August 2000, identified 152 PCIs treated with eptifibatide (bolus 180 pg/kg, infusion 2 pg/kg/min for 12-48 h) and 205 PCIs treated with abciximab (bolus 0.25 mg/kg, infusion 10 pg/min for 12 h). All patients received IIb/IIIa antagonists at the initiation of the intervention. Results: Patient characteristics were similar in both groups. In the eptifibatide group, the maximum ACT was lower (235 * 45 vs. 253 + 40, p
% (N=152)

Angiographic Success 97.5 Abrupt Closure 1.4 Residual dissection 3.5 0.7 No Reflow 1.4 Overall Major Complications Death 0.7 Q-wave MI 0.7 Emergent Coronary Bypass 0 Non Q-Wave MI 25.5 3.4 Repeat PTCA (target lesion) 31 CPK MB >3x normal Major Bleeding 3.3 Minor Bleeding 9.9 I’ = NS in all comparative groups (Eptifibatide vs. Abciximab) Conclusions: Eptifibatide is comparable cedural complications and in-hospital interventions.

to abciximab events after

Abciximab, % (N=207) 96.8

0 1.7 0 2.9 2.0 0

1.0 31.8 1.9 36 4.3 6.6

in regards to acute propercutaneous coronary

RANDOMISED STUDY OF OPTIMAL TIMING OF CLOPIDOGREL LOADING BEFORE CORONARY STENTING. A.Farshid. W. Abhavaratna*. Ll’rosser and I.Pratt. Departments of Cardiology and Haematology, The Canberra Hospital, ACT. Treatment with clopidogrel and aspirin following coronary stenting has reduced but not eliminated subacute stent thrombosis. The use of a loading dose accelerates clopidogrel’s antiplatelet effects, but the optimal timing of a loading dose has not been evaluated in clinical studies. Our aim was to compare the effect of a loading dose of clopidogrel on platelet aggregation, when administered 5 hours, 1 day or 2 days prior to coronary stenting. Forty-three patients with stable or unstable coronary artery disease, due to undergo coronary angioplasty, were randomised to receive 3OOmg of clopidogrel at one of the above times prior to the procedure. All groups received concurrent daily aspirin (300mg). Ex viva platelet aggregation in response to ADP and collagen was evaluated on blood samples taken at baseline (whilst on aspirin) and immediately prior to angioplasty. Baseline characteristics were comparable for all three groups in terms of age, sex and indication for coronary intervention. Patients treated with clopidogrel 1 or 2 days prior to angioplasty were found to have a significantly lower level of platelet aggregation compared with those treated 5 hours prior to the procedure (ADP 5uM: mean % aggregation 26.3 +/- 13.5 vs 35.7 +/- 10.3, p=O.O25). No significant difference in platelet aggregation was observed behveen patients commencing clopidogrel 1 or 2 days prior to coronary intervention (ADP 5uM: mean % aggregation 24.3+/14.8 vs 28.5 +/- 12.1, p=O.43). No patient had stent thrombosis or a CK elevation greater than twice the upper limit of normal. It was concluded that a loading dose of clopidogrel administered lor 2 days prior to coronary intervention produced a greater inhibition of platelet aggregation compared to a loading dose administered 5 hours before intervention.

Scientific

Meeting

of CSANZ

A RANDOMISED COMPARISON OF CLOPIDOGREL AND VERSUS TICLOPIDINE AND ASPIRIN AFTER CORONARY IMPLANTATION. C Fernandes* . ST Lo. HC Lowe, S Newoort. A Hookins. CP Tuereens Department of Cardiology, Liverpool Liverpool NSW

AlO5

ASPIRIN STENT A Wow, Hospital,

Background: The introduction of antiplatelet therapy with aspirin and ticlopidine after intracoronary stenting has decreased the risk of thrombotic stent occlusions (TSO). Ticlopidiie (T) induced neutropaenia post-stenting has altered many practitioners’ practise to either 2 weeks of T or use of Clopidogrel (C) instead with little evidence of benefit or safety. A recent study comparing the use of aspirin with T or C for 4 weeks after intracoronary stenting concluded that C was better tolerated than T although there was a trend to more adverse cardiac events in the C group. We are the first group to evaluate the tolerabilty and safety of aspirin with a 2-week course of T or C. Methods: After successful coronary stenting 308 patients were randomised immediately after successful stenting to two weeks of either T (n=156) or C (n=152). All patients received at least 3tig of aspirin prior to the procedure and aspirin was continued indefinitely. Patients assigned to T received 5oOmg immediately after the procedure and then 250mg bd for 2 weeks. The C group received 15Omg immediately after the procedure and then 75mg daily also for 2 weeks. Patients were followed by phone interview at 2 and 4 weeks and 6 months. The primary endpoint was the incidence of side effects directly attributable to the medication. Secondary endpoints were the incidence of study drug discontinuation and a combination cardiac endpoint (including cardiac death, TSO, urgent revascularisation and non-fatal myocardial infarction). Results: There was no significant difference in the number of patients in both groups who experienced side effects attributable to the medication (T= 31 vs C=24; p=O.35). The most frequent side effects were gastrointestinal (T=24 vs C=13) and rash (T=4 vs C=6); although few patients actually ceased therapy There was no difference in the need for study drug discontinuation in each group (T=5 vs C=l; p=O.21). There was also no difference in the incidence of combined cardiac events in each group (T=7 vs C=4; p=O.54). The incidence of thrombotic stent occlusion was low in both groups (2 in each arm). Conclusions: Whilst there was no statistically significant difference behwen the two groups in this relatively small randomised trial, there was a trend towards less side effects and drug discontinuation in the C group. In contradistinction to a larger earlier trial looking at 4 weeks of therapy we found no increased incidence of cardiac events in-patients receiving C. The combination of aspirin and clopidogrel post-stenting seems to be comparable in safety and efficacy to aspirin and ticlopidine, even when T or C is stopped after 2 weeks.

LOW RESTENOSIS RATE IN LONG TERM FOLLOW-UP AFTER CAROTID STENTING. B.Gunalmeam*. P.Rov. D.Baron and D.W. Muller. Cardiology Unit, St. Vticents Hospital, Sydney. Carotid stenting is gaining popularity as an alternative to carotid endarterectomy (CEA) for carotid occlusive disease. Between 12/97 and ll/OO, 53 pts (39M, 14F) with age 67.2+ 10.1 yrs (45-92) underwent 60 carotid stent procedures. 5 pts (9.4%) had bilateral stenting performed, 2 of these as part of the same procedure. Diabetes was present in 19. Pts (35.8%), significant 2 or 3 vessel coronary artery disease in 31 pts (58.4%); 10 pts (18%) had a history of previous CABG. 30 pts (56.6%) had bilateral carotid disease and 6 pts (11.3%) had had a previous carotid endarterectomy ; 1 pt having had bilateral CEA’s. 2 pts (3.8%) had high bifurcation lesions and 4 (7.5%) had had previous neck radiotherapy. 46 pts (86.8%) were unsuitable for CEA according to NASCET criteria. 19 pts (35.8%) were symptomatic from their carotid lesions, and the lesions in the remaining pts were identified during a pre-operative assessment prior to cardiac or major non-cardiac surgery. Of the 60 interventions; there was 1 major CVA (1.7%), 1 minor CVA (1.7%), and 1 TlA (1.7%). 10 pts (18.9%) suffered brief periods of hypotension. The median length of stay was 1 day, with 77% of patients being discharged within 24 hours of the procedure. 6-month clinical follow up was available in 37 pts and 12-month follow up in 12 pts. There was 1 major CVA at 9 months directly attributable to the stented artery. There were 2 deaths, 1 due to cardiac causes. Carotid Doppler scans were available in 18 pts, with all but 2 at greater than 12 months follow up. 2 pts had restenosed withm 6 months. In conclusion, carotid stenting appears safe in this high-risk cohort of pts and restenosis rates seem low in long term clinical follow up.

AlO6

49th Annual

Scientific

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of CSANZ

Heart,

PHYSIOLOGICAL EFFECTS OF CONTROLLED HYPOTHERMIA IN AWAKE PATIENTS UNDERGOING ELECTIVE PERCUTANEOUS CORONARY INTERVENTION. R. Whitbourn*. A. MacIsaac, Department of Cardiology, St Vincent’s Hospital, Melbourne Background: Currently, percutaneous coronary interventions (PCI) can be used to restore blood flow and limit myocardial damage during infarction. Previous animal studies have demonstrated that a significant decrease in core body temperature, may limit the amount of heart tissue damaged due to occlusion of coronary arteries. We hypothesised that awake hypothermia: 1. Can be safely induced and tolerated in awake subjects, and 2. Results in no significant rise in myocardial oxygen consumption. Aim: To evaluate the physiological effects, feasibility and tolerability of controlled, induced hypothermia, in closely monitored awake subjects in the cardiac catheterisation laboratory. Methods: In a group of 6 patients undergoing elective percutaneous coronary intervention, awake hypothermia was induced using a novel endovascular cooling balloon placed via femoral vein in the vena cava. Systemic, heart and pulmonary pressures, heart rate and physiological data including myocardial oxygen consumption were recorded. Results: All patients tolerated induction of hypothermia and no shivering was observed. A target temperature 33 degrees Celsius was able to be achieved in all patients. With induction of hypothermia, there was no significant change in blood pressure, heart rate or cardiac output. Mean myocardial oxygen extraction (% saturation) fell from 60% at baseline to 42% at hypothermia of 33 degrees Celsius (p=O.O2). Conclusion: Induced hypothermia is feasible, safe and well tolerated in awake patients undergoing elective percutaneous coronary intervention. Myocardial oxygen extraction is reduced during hypothermia. This study suggests that hypothermia may provide myocardial protection by reducing tissue metabolism during periods of myocardial ischaemia.

EXCESS CARDIOVASCULAR RISK AMONG DIABETICS IN URBAN ADULT AUSTRALIAN ABORIGINAL POPULATION. Pl Bradshaw*. FL ThomDson. E Wilkes. WA Heart Research institute Charles Gairdner Campus) and Derbarl Yerrigan Health Services.

AN (Sir

Deaths from diabetes and associated vascular disease are rising rapidly in the In a self-selected population of urban Australian indigenous population. Aboriginal people attending a heart health screening programme 22% of the 998 participants reported a history of diabetes. We examined the clustering of additional risk factors for cardiovascular disease among diabetics versus non-diabetics in this sample. Diabetics were more likely to be female, have a parent or sibling with diabetes, have a history of coronary artery disease and were older (mean 48 2 10.4 years) than the non-diabetics (37 + 10.6 years). Other risk factors are shown in the table below.

Mean systolic BP mmHg Mean diastolic Bl’mmHg Mean total cholesterol mmol/L Mean HDL mmol/L Mean LDL mmol/L Mean triglycerides mmol/L Current smokers Mean BMI BMI > 30 (obese) Mean waist circumference ems

Diabetes Mean + SD 131 f 10.7

No diabetes Mean k SD 124 f 15.7

83 A 10.7 5.52 t 1.2 1.12 -t 0.29 3.37 f 0.9 2.63 e 2.15 37% 32.4 r 6.2 62%

80 k 11.2 5.28 f 1.0 1.21 + 0.31 3.27 f 0.9 1.89 + 1.59 48.5% 29.3 k 6.3 42% 93.3 i 14.7

104.1 * 14.7

*P


Treatment of hypertension and hyperlipidaemia was equally ineffective for the diabetic subjects as for the study population overall. Of those reporting treatment for hypercholesterolaemia 7l% had a cholesterol >5.Ommol/L. The majority in both groups failed to meet National Heart Foundation goals for treatment of risk factors. While fewer diabetic people were current smokers, the proportion smoking was still alarmingly high. Conclusion: Urban Aboriginal people with diabetes are more likely to have higher blood pressures, total and LDL cholesterols and triglycerides, and lower HDL’s and to be more overweight or obese than those without diabetes, placing them at exceedingly high cardiovascular risk. Despite this, they are poorly controlled when under treatment.

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2001;

10

MULTI-CENTRE RANDOMISED CONTROLLED TRIAL OF COACHING PATIENTS QN ACHIEVING CARDIOVASCULAR HEALTH (COACH); A PROVEN METHOD FOR BRIDGING THE TREATMENT GAP IN CORONARY HEART DISEASE. M.J. V&& M,V.Jelinek. J.D. Best. mare. B. Ho. R. Newman, J.J,McNeil. The COACH study group, Melbourne, Victoria. Background: We have previously shown that coaching patients with coronary heart disease (CHD) resulted in a total cholesterol level that was 0,54mmol/L less than that achieved with usual care. The objective of this study was to determine if other coaches could achieve similar results in other hospitals. Methods: Patients with established CHD underwent a stratified randomisation by cardiac diagnosis in each of 6 teaching hospitals in Melbourne. Patients received either the coaching intervention (CI) or usual medical care (UC). The primary endpoint was the change in serum lipid profile from baseline to 6 months post-randomisation measured by the hospital laboratory which was blinded from treatment allocation. Results: Of 792 patients randomised, 33 1CI and 348UC completed the trial. 1 ATC 1 ATG 1 AHDL-C 1 ALDL-C 1 (95%CI) (95%CI) (9S%CI) (95%CI) Coaching 0.65 0.20 - 0.09 0.66 Intervention (0.51 to 0.78) (0.08 to 0.32) (-0.12 to -0.06) (0.54 to 0.78) Usual Care 0.20 0.16 -0.12 0.24 (0.05 to 0.33) (0.04 to 0.28) (-0.15 to -0.0X) (0.13 to 0.36) Difference: 0.45 0.04 0.03 0.42 Coaching vs (0.26 to 0.63) (-0.13 to 0.21) (-0.02 to 0.07) (0.25 to 0.58) Usual Care 1 I I P I 0.0000 1 NS NS 1 0.0000 I At 6 months. the serum TC and LDL-cholesterol levels were sisniticantlv lower in the CI than the UC groups: mean TC (95%CI) 4.37 (4.28 to 4.48) mm&L vs 4.70 (4.59 to 4.81) mmol/L (P
SECOND AUSTRALIAN NATIONAL (ANBPP) - PROGRESS REPORT. yWine. L :, F R Rvan. nnin an sure Research Council of Australia, ANBM, Melbourne, Vie.

BLOOD

Baker

PRESSURE

STUDY

ators. High Blood PresMedical Research Institute,

ANBP2 has been designed to compare the outcome (total cardiovascular events, fatal and non-fatal) of ACE inhibitorversus diuretic-based regimens for the treatment of hypertension in elderly hypertensives (aged 65-84 years) over a 5 year treatment period. Secondary aims of the study include the identification of genetic markers related to hypertension and outcome, the association of left ventricular hypertrophy (LVH) and 24hr ambulatory blood pressure (ABPM) recording with outcome and the evaluation of the effects of treatment regimens on quality of life, LVH and ABPM. A health economic analysis is also being undertaken. The study is being conducted in over 1000 general medical practices across Australia using a PROBE designl. Following completion of a screening and run-in phase to determine eligibility (average untreated sitting blood pressure on the 2nd and 3rd screening visits t 160 mm Hg systolic or 2 90 mm Hg diastolic and no recent cardiovascular event or other serious intercurrent illness), subjects were randomised to receive ACE inhibitor or diuretic -based therapy. Monitoring of outcomes and blood pressure control is determined by six-monthly reviewing patient records. 2300 (38%) newly diagnosed hypertensives and 3783 (62%) previously treated patients were randomised. 49% of the study cohort are female and the average age is 72 years with 70% being in the 65 - 74 year age group. Mean entry BP is 167/91 mmHg and mean body mass index is 27.0 kg/m2 7% of subjects have diabetes, 10% have had previous coronary heart disease, 5% previous cerebrovascular disease and 7% are current cigarette smokers. 4897 (81%) subjects are participating in the genetic study. 1291 have had baseline echocardiographic recordings with 230 (17%) having completed the 3 year follow-up study. 735 baseline ABPM studies were undertaken with 528 (71%) and 295 (40%) having undergone first and second follow-up recordings. 1695 subjects have participated in the quality of life project with response rates of over 90% for each of the annual follow-up questionnaires. Follow-up blood pressure recordings indicate that 66 - 73% of subjects have achieved target systolic and diastolic blood pressure levels (<140/90 mmHg) respectively. After 17,321 patient years of follow-up, 462 major cardiovascular events (firstevents only) have been confirmed (rate = 28.3 / 1000 patient years). ANBPZ is entering the final year of observation with an anticipated close-off date scheduled fo; the last quarter of 2001. LManagement Committee. Clin Exper Physiol Pharmacoll997; 24188 192.

Heart,

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2001;

49th Annual

10

Scientific

Meeting

of CSANZ

AlO7

SOCIOECONOMIC STATUS AND OUTCOME AMONG AUSTRALIANS IN THE LIPID STUDY. R. Stewart,* I. Simes, S. Mulrav. W. Ghao. K. Sharoles. H. White. D. Colauhoun and A. Tonkin for the LIPID study investieators. Green Lane Hospital, Auckland and NH&MRC Clinical Trials Unit, Sydney.

CARDIOGENIC SHOCK AND MYOCARDIAL INFARCTION IN 19 AUSTRALIAN TEACHING HOSPITALS. C Blanton & FL Thomuson* on behalf of the Health Roundtable collaboration. Department of Cardiovascular Medicine & Gairdner Campus of the Western Australia Heart Research Institute, Sir Charles Gairdner Hospital, Perth.

Socioeconomic [SE) differences in coronary heart disease risk factors, symptoms, interventions and mortality were assessed in 5948 Australians with a previous acute coronary syndrome who participated in the Long term Intervention with Pravastatin in Ischaemic Disease (LIPID) study. Method: SE status was estimated by linking street address at randomisation to household income by census collection district in 1991. Subjects were divided into three SE groups; 1. Weekly household income for area < $A500, (29%), 2. $A500-699, (37%), 3. aA700, (33%). Baseline clinical information and outcomes over a median of 7.8 years were recorded as part of the LIPID and LIPID cohort studies Results: At baseline there was no significant difference by SE group in serum lipids, hypertension or diabetes, but obesity (BMI>SO; 1. 21%, 2. 18%, 3. 15%, p1 symptoms (1. 38% 2. 35% 3. 31%, p
Introduction: Of the complications of acute myocardial infarction (AMI), cardiogenic shock (CS) has the highest mortality rate. This study profiles contemporary data on CS from 19 Australian teaching hospitals Methods: All patients coded in the 1996/97 financial year with an AMI, International Classification of Disease (ICD) 9 code of 410.*1, (where * is the location of the infarct, any location and 1 represents the initial episode of care for a newly diagnosed AMI) who were admitted via the emergency department to 19 Australian teaching hospitals have been included in the database. (n=6615). This routinely collected information included demographics, comorbidities, procedural and admission information. 219 patients (3.3%) were coded with CS using ICD 9 criteria. Hospital mortality rates by AMI location were anterior (62%), inferior (60%), lateral (70%) & unspecified (90%). Those with ‘unspecified’ location had a significantly (~~0.05) higher in-hospital rate than those patients with other locations. 85% of the mortality of those patients with an unspecified location for their AM1 died within the first 4 days of admission. A comparison was made between the SHOCK trial registry patients (Hochman et nl, IACC 2000;36:10&3-70) and patients with AM1 complicated by CS from Australian hosoitals

HEART FAILURE AND THE AGEING POPULATION: AN INCREASING BURDEN IN THE ZlST CENTURY? S. Stewart’. K. Ma&hire. S. Caoewell and 1.1. McMurrav CR1 in Heart Failure, University of Glasgow and Department of Public Health, University of Liverpool, Liverpool, United Kingdom. Background: Despite an overall decline in age-adjusted mortality from coronary heart disease in developed countries overall, there is evidence to suggest that the number of patients with heart failure (HF) is increasing. This is due to two separate trends. Firstly, the proportion of elderly in the population is rising and secondly, survival in those patients with heart disease is improving. We have used contemporary epidemiological data to project the future burden of HF in Scotland. Methods: Scotland, like many industrialized countries, has a stable but progressively ageing population (5.1 million). We applied contemporary and accurate epidemiological data concerning the prevalence, general practice (GP) and hospital activity related to HF to the whole Scottish population. Applying data on an age and sex-specific basis we estimated the following: 1) population prevalence of HF, 2) annual number of GP consultations for HF, 3) incident HF hospitalizations per annum and 4) all hospitalizations associated with a principal diagnosis of HE These data were applied to the projected Scottish population for the period 2000-2020. Results: We estimate that there are currently 40,000 and 45,000 Scottish men and women aged > 45 years, respectively, requiring treatment for HF. Based on population changes alone these figures will rise by 2,300 (6%) and 1,500 (3%) by year 2005, and by 12,300 (31%) 7,800 (17%) in the longer-term (2020), respectively. On the same basis, the annual number of male and female GP visits is likely to rise by 6,400 (6%) and 2,500 (2%) by year 2005, and by 35,200 (40%) and 17,300 (16%) in the longer-term (a total of 124,000 and 126,000 visits), respectively. Based on contemporary trends in hospitalization rates we estimate that in the year 2000 about 3,500 men and 4,300 women in Scotland experienced an incident hospitalization for HF. By the year 2020 these figures are likely to increase by 52% (1,800 more) and 16% (717 more) in men and women, respectively. However, if, at the same time, trends in short-term casefatality rates remain constant, the number of men who survive this event will increase by 59% (1,700 more). Overall, the annual number of male and female hospitalizations associated with a principal diagnosis of HF is expected to increase by 34% (from 5,500 to 7,500) and 12% (from 7,800 to 8,500), respectively, during the next 20 years. Conclusions: ln summary, though surrounded by inevitable uncertainty, our projections, based on the best available data, do suggest the burden of HF will continue to increase substantially over the next two decades (more so if secondary HF admissions are considered). Future health service planning must take this into account.

n *kF M& Diabetic Mortality (in-hospital) ’ pio.001 Conclusion: the limited that in the myocardial

Australian teaching hospitals 219 73.2 (t 10.9) 54% 118 66.7%

SHOCK trial registry 1190 6R.7 (f- 11.8) 60% 33%’ 61.4%

The profile of CS documented in Australian teaching hospitals but universally available technique of ICD coding is similar international registry Despite recent advances in treatment infarction, the mortality of CS remains very high.

by to of

CARDIOMYOCYTE APOPTOSIS AND THE SIGNALLING PATHWAY IN CHRONIC HEART FAILURE. L. liar&. S. Hunvor. C. dos Remedios. X Huann Cardiac Technology Centre, Department of Cardiology, Royal North Shore Hospital, St. Leonards, Australia, and Institute for Biomedical Research, Department of Anatomy and Histology, University of Sydney, NSW, 2006, Australia Cardiomyocyte loss via apoptosis contributes to progression of heart failure (HF) but the mechanism remains unclear. We examined involvement of a prominent apoptosis signalling pathway, the Fas (TNF super family) death receptor pathway in cardiomyocyte apoptosis and the relationship between wall stress and expression of Fas-ligand (FasL) in a sheep model of chronic HF. The occurrence of apoptotic cardiomyocytes detected by TUNEL assay was increased 11.4 fold (to 0.5%) in HF. We compared protein and mRNA expression in left ventricles from normal and failing hearts. Using Western blotting, we found in HF an altered expression of Fas (?1.53-fold), FasL (f1.96-fold), caspase3 (?2.6-fold), caspase-8 (f2.7-fold) and an active cleavage peptide of caspase-8, p20 (?5.55-fold). By gene array technology, mRNA expression of caspase-9 was found to be upregulated (1.7-fold). Immune-histochemistry was used to localize FasL and caspase-8 to intercalated discs, whereas Fas was distributed throughout cytoplasm and caspase3 concentrated in the perinuclear zone. HF was produced by sequential coronary microembolisation resulting in micro-infarctions. Six months after HF was established (LVEF 35%), sheep remained in a stable chronic state as assessed by hemodynamic and echocardiographic measurements. Ventricular dilatation, without wall thickening, caused a 2-fold increase in LV wall stress which was linearly correlated with protein expression of FasL (FasL = 161 + 4.57*LV wall stress, r2 = 0.8, p < 0.001). We conclude that in untreated chronic HF, increased wall stress induced by chamber dilatation may be responsible for activating Fas/FasL and caspase-8 interaction at intercalated discs, the principal zone of wall stress. Apoptosis is then executed by activating effector caspase3 either directly by caspase-8 or via a caspase-9 mitochondrial pathway.

AlO8

49th Annual

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of CSANZ

Heart,

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and Circulation

2001; 10

TARGETED alA-ADRENERGIC RECEPTOR OVEREXPRESSION INDUCES ENHANCED CARDIAC CONTRACTILITY BUT NOT HYPERTROPHY F.. K&even. J.F. Arthur. E.A. Woodcock. M. Fenelev and R.M. Graham Victor Chang Cardiac Research Institute, Sydney, NSW

ASSOCIATION OF SERUM CONCENTRATION OF BILIRUBIN WITH EXTENT OF CORONARY ATHEROSCLEROSIS P. Nmtven-Do? D.M. Colauhoun.. F.A. Harden. P.M. Will. B.J. Hicks Core Research Group, Wesley Hospital and The University of Queensland, Brisbane, Australia

Activation of the cGradrenergic receptor (a,,-AR)/Gq pathway has been implicated as a critical trigger for the development of cardiac hypertrophy. However, direct evidence from in viva studies is still lacking To address this issue, transgenic mice with cardiac-targeted overexpression of the a,,-AR were generated, using the rodent a-myosin heavy chain promoter. Five independent lines with 4- to I70-fold overexpression were established. Heterozygous animals displayed marked enhancement of cardiac contractility, evident from increases in dP/dt,,, (80%. p
Background: An inverse relationship between low serum bilirubin concentrations and an increased risk for coronary artery disease (CAD) has been demonstrated. Modified low-density lipoprotein has been shown as the most significant factor in the development of atheromatous plaques. Bilintbin, a natural anti-oxidant may attenuate the oxidizibility of lipids and lipoproteins and so inhibit atherogenesis. Methods: A retrospective analysis of 1140 patients who underwent coronary angiography at the Wesley Hospital was undertaken. Sex, age, serum bilintbin, serum cholesterol and triglycerides of 828 males and 3 12 females were recorded. The severity of CAD was scored as the number of diseased vessels, with significant stenosis deftned as 70% or greater reduction in luminal diameter. Results: Analysis showed a relationship between age, male sex and degree of the disease. No relationship was shown between total serum bilirubin concentration or serum lipids and the level of CAD. Conclusion: No relationship between the total serum bilirubin and the level of CAD was observed. This may be a reflection of the blunt tool for estimating disease severity. Further study of the relationship between serum bilintbin and CAD is warranted using perhaps intravascular ultrasound, Calcium scoring or clinical outcomes in prospective studies.

DISTAL MICROVASCULAR CONSTRICTION IS A MAJOR MECHANISM INTERRUPTING FLOW FOLLOWING ATHEROSCLEROTIC PLAQUE RUPTURE. EVIDENCE FROM A NOVEL PLAQUE RUPTURE MODEL Andrew J. Tavlor*. Alex Bobik. Michael C. Berndt. Debra Ramsav, Garrv Jennings. Baker Medical Research Institute and Alfred and Baker Medical Unit, Melbourne, Australia. BACKGROUND: Rupture of atherosclerotic plaque, resulting in local thrombus formation and marked reductions in distal flow, is a pivotal event in unstable coronary syndromes. We tested the hypothesis that following plaque disruption, a marked rise in distal microvascular resistance is an important mechanism in the interruption of blood flow. METHODS: Thirty-two rabbits underwent endothelial denudation of the let? iliac artery and cholesterol feeding to induce a localised, obstructive, angiographically severe (AHA Type IV-like) lesion. Lesions were then disrupted with a stiff angioplasty wire and the effects of plaque disruption on distal flow and pressure recorded. Capillary patency following plaque disruption was assessed using intra-arterial India ink to determine the number of functional capillaries in the distal muscular bed. Morphology of the atherosclerotic lesions and associated thrombi was also examined to assess lumen restriction. RESULTS: Mechanical plaque disruption reduced mean flow from 5.041kl.21 ml/min to 1.23+0.37 mllmin (P
CAN THE AUSTRALIAN FOOD SYSTEM COPE WITH A v MEDITERRANEAN DIET? S. Somerset’, D.M. Colauhoun*‘. P Hotsle? for the OLIVE study investigators. ‘Grifftth University, Gold Coast, *Core Research Group, Wesley Hospital, University of Queensland, Brisbane, Australia. Background: Mediterranean diet (MD) describes traditional dietary patterns bordering the Mediterranean Sea. Pasta, coarse breads, beans, nuts, seeds, olive oil, wine, and seasonal fruits and vegetables predominate. MD is sustained by cultural factors and is ecologically sustainable. The MD may be an appropriate strategy to combat coronary heart disease (CHD) in non-Mediterranean countries like Australia. Methods: Australian agricultural production data was used to assess current amounts and types of food produced in Australia. The prescriptive MD requirements were based on those described for the Cretan diet in the Seven Countries study. Projected annual food requirements for individuals were calculated on the basis of a diet containing 7509 kJ per day. Results: There are major changes in agriculture with 4000 hectares of new olive trees throughout Australia and projected production being 10,000 tonnes(t). Requirements (t per annum) of a Cretan type MD diet in Australia are: 1 I” orevention 1 2” orevention 1 Current oroduction

..

I 280 000 t aoole 220 000 t banana Conclusion: local food production is not adequate for widespread adoption of Cretan type MD for primary or secondary prevention of CHD. Within a decade MD may be feasible for secondary prevention, but climate and geography may limit adequate production.

I Current

Heart,

Lung

and Circulation

2001;

10

49th Annual

Scientific

Meeting

of CSANZ

A109

POTENTIAL IMPACT OF CORONARY CALCIUM SCREENING ON TARGETING CHOLESTEROL LOWERING THERAPY IN ASYMPTOMATIC MIDDLE AGED MEN. SM.NidorP. RGT Walker. FL Thomuson. S.Nair and D.Grout Sydney Heart Image, NSW and West Australian Heart Research Institute, WA, Australia.

RENAL ARTERY INTERVENTION BY THE CARDIOLOGIST: INDICATIONS AND PROCEDURAL. RESULTS. C Armais’. N B Eastem Heart Clinic & Prince of Wales Hospital, P.andwick NSW Australia

Background: Recent post coronary clinical trials have shown a benefit in the use of statin therapy for secondary prevention irrespective of the baseline LDL level; other studies have shown that secondary prevention is far more cost effective than primary prevention. If demonstrable coronary calcium were used to identify asymptomatic subjects with coronary atherosclerosis suitable for secondary prevention, statin therapy could be targeted to those most likely to benefit. We compared the policy of targeted therapy based on secondary prevention guidelines in those with CAC to a policy of primary prevention following the NCEP guidelines based on LDL levels in asymptomatic men. Method: The prevalence of coronary artery calcium (CAC) in a cohort of 6059 asymptomatic men who underwent CAC screening was determined in relation to decile of age. Each age group was divided into quartiles based upon the level of LDL and the prevalence of CAC was determined in each quartile. Results: 1298/4514 (27.2%) of men in this cohort were aged 40-49. The prevalence of CAC in this group was 40% and the prevalence of CAC in relation to quartile of LDL was as shown. Using current NCEP guidelines (a) about 50% of men aged 40-49~ would be eligible for treatment, (b) 50% of those treated would have no detectable CAD, and (c) almost 50% of those with detectable CAD would fail to qualify for therapy. On the basis of CAC screening, only 40% of men, each with detectable CAD would receive treatment. Conclusion: Screening for CAC may be an effective means of selecting asymptomatic people for cholesterol lowering therapy as it ensures that it is given to those people with anatomically demonstrable disease

physicians. The indications aad procedural data on the first 40 patients were reviewed. METHODS All procedures were performed with 014 wires, 7&8 Fr Guides, coronary balloons for prodilatation and sawer peripheral sterns on 5.5 to 7mm balloons in a lab with DSA capabilities The brachial approach was used for downpointing renal arteries aad severe orial disease Empirical reso-pmteaive agents and current anti-platelet rc8imens wem used All cases were planned with renal

QUARTILE Mean LDL (mg/dL) ‘KAC

I 94 39

II 127 31

III 149 45

IV 187 45

WINE IMPROVES ENDOTHELIAL DYSFUNCTION lN MEN WITH CORONARY ARTERY DISEASE A.P. Whelan*. W.H.F. Sutherland. M.P. McCormick. D.J. Yeoman, S.A. de Song. M.J.A. Williams. Department of Medicine, University of Otago, Dunedin, New Zealand Background: Levels of antioxidant polyphenols are higher in red than white wine and are thought to contribute to the reduced cardiovascular risk associated with moderate consumption of red wine. Because polyphenols improve endothelial function, which in turn may reduce cardiovascular risk, we examined the acute effects of drinking white and ted wine on endothelial function in subjects with coronary artery disease (CAD). Methods: Fourteen men with angiographically proven CAD took part in the study. Flow-mediated endotheliumdependent dilatation and glyceryltrinitrate-induced endothelium-independent dilatation of the brachial artery were assessed before, 60 and 360 min after ingestion of 4ml/lcg of red or white wine in a randomised, single blind crossover design trial. Results: The 14 subjects had a mean age of 58 f 6 years and a body mass index of 28 + 4 kg/m2. Wine ingestion resulted in a fall in systolic and diastolic blood pressure and an increase in heart rate at 60 min with a return to baseline at 360 min. Alcohol levels increased at 60 min with a fall to baseline at 360 min. Triglycerides increased between baseline (white wine 1.47 + 0.52 mmol/l; red wine 1.50 f 0.5 Immol/l) and 360 min (white wine 2.30 f 0.67 mmol/l; red wine 2.42 f 0.67 mmolil; P < O.OCOS). Endothelium-dependent dilatation was impaired at baseline (white wine 1.6 + 1.9%; red wine I .8 f 1.7%). Endothelial function improved at 360 min after both wines (white wine 4.7 + 2.2%; red wine 3.4 + 2.9%. P < 0.0005). There was no significant difference in endothelium-dependent dilatation at 360 min between the white or red wine. The red wine had a significantly higher content of total polyphenols than the white wine (1.17fl vs. 0.2lg/l) but no change was observed in plasma polyphenol levels after either wine.

Conclusions: Wine improves flow mediated endotbelium-dependent dilatation in men with coronary artery disease. The benefit appears to be independent of wine polyphenol content.

BACKGROUND Gpponems of pemutaneons transluminal renal angioplastyl stenting (PTRA) remain concerned that inappropriate lesions may be dilated if the procedure is performed by cardiologists (the “occnlo stenotic reflex”). PTRA began at the Eastern Heart Clinic in May 1998 in close collaboration with the renal

physicians and standard work up included renal U/S & doppler, perfusion scans and

Cr Clearance. Data was obtained from

a computer&d

database entered

prospectively, and from medical records. Follow up is planned at 6 and I2 months. RESULTS: 40 procedures were performed on 38 patients between May 1998 and Oct. ZOOO. The brachial approach was used in 24 (60%) of cases. The indications for pm&ores were: ret&tory hypertension SO% (20) worsening renal failure, 12 5% (5), flash pulmonary o&ma 7.5% (3), restenosis 5% (2) and combination of the

above 25% (10). Lesion severity was *h

stenosis in 62.5% ofpatients, 70-90% in

another 25% and less than 70% (but with evidence of functional severity) in 12.5%. Stems were deployed in 87.5%, angioplasty only was performed in 3 cases (7 5%, I had tibromusadar hyperplasia) and 2 procedures were abandoned Lesion soccess

was achieved in all cases that proceeded. There were no deaths. Complications included 1 patient who snffered a cerebral infarct, 1 case of leg iscbaemia which resolved witbout surgery, and 3 brachisl attety complications (2 requiring surgery). Post procedural creatinine levels remained stable or improved in all except one

patient who had llcute renal failure prior to the procedure. Severs1 patients had early falls in blood pressure, 3 reqnired extended hospital stay due to symptomatic hypoteasion. CONCLUSION: All patients in this series undergoing PTRA by cardiologists had a strong indication for the procednre (refractory hypertension, flash pulmonary o&ma and progressive renal dystimction). Results to the renal artery end kidney were excellent (primary success in all cases with stable or improved in hospital renal function), however vascular complication rates (lo??) were higher than published data due to the need to use the brachial approach in 60% of cases

RENAL ARTERY STENTING FOR RENAL ARTERY STENOSIS - SIMPLIFIED INTERVENTIONAL APPROACH. G.G.Gearv’. A.R.Denniss and D.L.Ross Department of Cardiology, W&mead Hospital, Sydney, NSW. Renal artery stenting to treat renal artery stenosis (RAS) is more frequently being performed by Interventional Cardiologists. Radiologists tend to use relatively high profile equipment. We describe our initial experience using familiar low profile coronary angioplasty techniques similar to that used for ostial saphenous vein graft stenting. Sixteen stems were deployed in 13 patients (pts) with mean age 64 (range 40-79). Two pts had bilateral renal artery stenting. All pts had difficult to control hypertension. Nine of the pts had positive or suspicious DTPA scans for significant RAS. Comorbidities included coronary artery disease 8 pts (62%), peripheral vascular disease 5 pts (38%)‘ cerebrovascular disease 5 pts (38%), diabetes 3 pts (23%). Creatinine was <14Oumol/L in all pts. The ostium of the renal arteries were engaged with 8F renal or coronary guides and the lesions crossed with 0.014” extra-support guide wires. Lesions were pre-dilated with coronary balloons and Herculink (Guidant) or coronary stents (3) deployed in all pts using a monorail approach. All stents were successfully deployed and mean lesion severity was reduced from 79% (60.95%) to 2% (0.10%) Translesional mean pressure gradients were measured in 11 procedures and were reduced from 2lmmHg (5-60mmHg) to 0.2mmHg (O-2mmHg). There was a poor correlation between the angiographic severity of the stenoses and the pressure gradients, There were no procedural complications. One patient developed back pain of uncertain aetiology 2 days post stenting. There was no significant change in serum creatinine post procedure (mean112 pm and 104umol/L post). Antihypertensive drugs were reduced from a mean of 3.3 (range 2-5) prior to admission to 0.4 (range O-l) at discharge. In conclusion, our initial experience shows this coronary like approach to renal artery stenting, using techniques familiar to Interventional Cardiologists, is relatively simple and can be performed with a high success and low complication rate. The early results in control of blood pressure are encouraging although long term follow up will be required.

Al

10

49th Annual

Scientific

Meeting

of CSANZ

Heart,

Lung

and Circulation

2001; 10

INCIDENCE OF RENAL ARTERY STENOSIS IN PATIENTS UNDERGOING ROUTINE CORONARY ANGIOGRAPHY. G,G.Gearv.D. Wagstaff and D.L.Ross Cardiology Units, Westmead and Westmead Private Hospitals, Sydney, NSW.

IS THERE A GENDER DIFFERENCE IN OUTCOMES FOLLOWING CAROTID ARTERY STENTING? G. AlMubarak. Lenox Hill Heart and Vascular Institute of New York, New York.

The reported incidence of renal artery stenosis (RAS) in patients (pts) with coronary artery disease (CAD) and various risk factors varies widely. Our aim was to find out the incidence of significant RAS (50% or greater luminal diameter) in a prospective group of pts having routine coronary angiography for known or suspected CAD. Exclusions included creatinine >2OOumol/L, primary or booked angioplasty, shock or operator concerns about excessive dye load. A contrast injection in the descending aorta was done following the left ventriculogram. Selective renal angiograms could be performed at operator discretion if aortogram pictures were suboptimal. A total of 684 pts were screened from January to July 2000. A summary of the results is shown in the table.

Background: Operative morbidity and mortality from carotid endarterectomy (CEA) is higher in women than in men. It is unknown whether carotid artery stenting caries a similar higher peri-procedural risk for women. Methods: Between September 1994 and Sept 2000, 712 patients (805 vessels) underwent carotid artery stenting. There were no differences in presence of hypertension, smoking, diabetes, hypercholesterolemia, history of prior CEA, contralateral internal carotid artery occlusion and symptom status between the men and women. There were more women over 80 years of age compared with men. Results: There were no differences in % diameter stenosis pre and post stenting, the type of stents used and haemodynamic changes during the procedure. There were also no differences in per&procedural and 30-day clinical events (see table). On long-term follow-up (21 & 19 mo), there were no differences in late ipsilateral stroke between the two groups (96 + 2% vs 95 ? 3%, for men vs women respectively, P = NS).

Hypertension

224 pts

No CAD No RAS 223 pts 92 (41%) 8 (4%) 11 (5%) 11 (5%)

RAS lpt (0.4%) 0 1 0 0

PVD CVD Diabetes 3 vessel disease LMCA PVD-peripheral vascular disease. CVD-cerebrovascular LMCA- left main coronary artery disease

CAD No RAS 398 pts 211(53%) 48 (12%) 28 (7%) 91 (23%) 149 (38%) 29 (7%)

460 pts RAS 62 pts (13%) 41 (65%) 27 (43%) 13 (21%) 19 (30%) 34 (54%) 5 (8%)

disease.

In pts with CAD and RAS there was a statistically higher incidence of PVD (p=O.OOOl), CVD (p= 0.0089) and 3 vessel disease (p=O.Ol) when compared to pts with CAD and no RAS. There was a trend towards a higher incidence of diabetes and hypertension. Bilateral RAS was found in 13 of the pts with RAS (21%). Conclusion: ln pts with CAD there was a relatively high incidence of unsuspected RAS (13%). In the pts with RAS there was a high associated incidence of other vascular disease. RAS was rarely found in pts without CAD.

CAROTID ARTERY STENTING SINGLE CENTRE EXPERIENCE. NAl-Mubarak.. Institute of New York, New York.

WITH NEUROPROTECTION - A G New’. G S Roubin. S S Iver. Lenox Hill Heart and Vascular

Background: To prevent cerebral embolism during carotid artery stenting, various protection devices have been introduced. The safety and efficacy of these systems are currently under investigation. Methods: We performed carotid artery stenting using a variety of distal protection devices [Percusurge GuardWirerM, MednovaTM , Accunetr”] in 127 symptomatic and asymptomatic patients. Patients were treated with a filter device versus distal balloon occlusion according to their collateral circulation. All patients had a NIH Stroke Scale performed before and within 24 hours after the procedure. Results: Procedural success was 99.8%. There were 2 minor strokes (1 periprocedural and 1 occipital stroke 2 weeks post-procedure) due to embolic events. There was also 1 retinal embolus (l.l%, non-cerebral) and 1 hyperperfusion syndrome (1.1%) in the GuardWireTM group. The only death was due to intracranial haemorrhage also in the GuardWireAllO group. Acute Embolic Events Patients(n) Minor Stroke Malor Stroke

GuardWirP 90 2 (2.2%)

0

MednowJTM 26 0

AccunettTM 3 0

0

0

Conclusion: Protected carotid artery stenting appears safe and effective in protecting the brain from embolic events. Distal protection devices may improve the peri-procedural risk of embolic stroke.

Pert-Procedural

and 30-Day Events

Patients

Arteries Minor non-fatal stroke Major non-fatal stroke Fatal stroke Non-neurological death

FeIlI& 238 (33%) 264 (33%) 9 (3.4%) 3 (1.0%) 1 (0.4%)

0

Male 474 (67%) 541 (67%) 26 (4.8%) 5 (0.9%) 3 (0.6%) 5 (1.1%)

Conclusion: Procedural and late outcomes following carotid artery stenting appear to be similar for men and women. Carotid artery stenting may be the preferred technique for treating women with significant carotid disease.

FEMORAL ARTERY HAEMOSTASIS WITH 6F PERCLOSE CLOSERTM DEVICE: IMMEDIATE AND SHORT TERM CLINICAL RESULTS OF 350 CASES. P.L. See*. LT. Meredith. R.W. Haroer. Gl Barron. SG Worthlep M. Cardiac Catheterisation and Interventional Cardiology Laboratory, Monash Medical Centre, Melbourne, Australia. In an era of increased utility of antiplatelet therapies and shorter hospital stays following percutaneous coronary interventions (PCI), immediate, secure and effective haemostasis of the arterial access site is paramount. Method: We assessed the immediate and short term vascular outcomes of 350 patients (250 male and 100 female, mean age 64 years, range 17 to 91 years) following closure of 352 femoral access sites (316 right, 32 left and 2 bilateral) using the 6F Perclose Closer rM device, following PC1 ( 213 patients, 60.8%) or cardiac catheterisation ( 136 patients, 38.8%) and one neuro coil embolisation case (0.4%) between April 2000 to January 2001. Deployment times are presented as mean + SEM. Results: One hundred and fifty nine patients (45%) had previous ipsilateral femoral arterial punctures or a previous closure device within the past 12 months and 37 (10.6%) had difficult punctures. The 6F Close? device was successfully deployed in 324 cases (93%). Twenty six cases (7%) were unsuccessfully deployed (1 case required vascular surgical intervention for isolated suture capture of the adventitia). The mean deployment time was 6.9 + 19mins. The 6F CloseT device was used to close 6F arterial punctures in 258 cases (73%) and 7F punctures in 94 cases (27%). Forty four patients (13%) were receiving either Reopro or Tirofiban, of which 2 cases (4.5%) were unsuccessfully deployed. Thus there was no significant differences in outcomes based on Reopro or lirofiban usage. In the cases where haemostasis was achieved (324 cases); this was instant in 258 cases (80%) but 5 to 15 mins. of digital pressure was required in the remaining 66 cases ( 20%). Six patients (1.8%) had mild late oozing (>I hour). At 24 hours: Extensive bruising (>lOcm) occurred in 4 patients (1%) and 3 (0.8%) had moderate haematomas (5 to 10cm). Groin tenderness or discomfort was experienced in 26 patients (7.4%). There were no false aneurysms or large haematomas. No patient required blood transfusion. At 1 week: Extensive bruising occurred in 2 patients (0.5%) and 2 (0.5%) had moderate haematomas. Mild discomfort was reported in 25 patients (7%). Two patients (0.5%) were hospitalised for local infection requiring antibiotic therapy. Conclusion: The 6 F CloserrM device is a safe and effective means of achieving immediate arterial puncture site haemostasis. Its use is associated with a very low incidence of major vascular complications. Its usage enables early patient mobilisation and the institution of aggressive antiplatelet therapy (Reopro or Tuofiban) without compromising access site haemostasis.

Heart,

Lung

and Circulation

2001;

49th Annual

10

NATURAL HISTORY OF AORTIC STENOSIS IN 542 ADULT PATIENTS DETERMINANTS OF RATES OF PROGRESSION. G M Scalia*, D 1 Burstow The Prince Charles Hospital. Brisbane, AUSTRALIA Background: Several small series have followed patients over time to determine the rate of progression of Aortic Stenosis (AS). Predictors of rate of progression may aid the timing therapeutic interventions. The effect of age and aetiology remain to be determined. Patients: Data was reviewed from pts attending from 1994 to 2001. Patients were selected by Continuous wave Doppler criteria (native aortic valve Vmax>25m/s). Patients with z measurements 26 months apart were studied across time. Each patient’s baseline measurements acted as t=O data. The overall absolute progression (cm2) and rate of progression of aortic valve area (AVA) by continuity equation (cmr/year) and peak b mean gradient progression (mmHg/yr) was calculated for the total follow-up period for each patient. Overall summary data and multiple linear regression was used to determine if any echo parameter at baseline predicted rate of progression. Results: 542 pts aged 18-88yrs were followed for 20.45t17.5months (rangelo-81). Baseline AVA (1.27+0.41cm2) fell linearly -0.19 10.41 cm*/yr (-23 +43%/yr, )AVA=years’-0.054 -0.71 cm2/yr, r2=0.94), peak gradient (50+23mmHg) rose linearly 5,5+17mmHg/yr (56+21O%/yr, P=O.81) and mean gradient (29+15 mmHg) rose by 3.6+11.7mmHg/yr (52+167%/yr, rz=0.91,see figure A). No echo parameter (AVA, peak & mean gradient, LV mass, age) predicted rate of progression by linear regression. However, 95 pts aged <50yrs (36+lOyrs),(probably bicuspid etiology) progressed much more slowly (-6+36 %/yr vs -25+44%/yr, p=O.O02) than the 450pts aged >50 (70+9yrs) most likely with calcific aortic stenosis see B.

Scientific

Meeting

of CSANZ

Al

11

ANGlOPI ASTV IS SIIPFRIOR TO THROMBOLYSIS FOR IN A MANAGEMENT OF ACUTE MYOCAR- DIAL~~ INFARCTION COMMUNITY SETTING. Nasr T.. Keat K’. Nrr M.K.C., Maclntvre C.R., Emnson M. Rubin G.. Fitzpatrick D. and Ross D.L. Departments of Cardioloev. Public Health and Communih ~‘Medicine, westmead Hospital and Depart&it of Cardiology, Nepean Hospital, Sydney, Australia. PR,MARY L

I . . . . . . . . . .

.

.

. . -

_ - .

_ . _ - .

.

. -

- - .

-

. _ _

Several small randomised trials have shown that primary angioplasty (PPTCA) is superior to thrombolysis (TL) for the management of acute myocardial infarction (AMI). These results, however, have been difficult to duplicate in a community setting - raising doubts as to the widespread applicability of PPTCA. We have therefore undertaken a prospective parallel comparison of PPTCA and TL in a community setting. Methods: A prospective observational cohort study was performed comparing parallel strategies for the management of AM1 in two tertiary institutions located in Western Sydney - PPTCA atWestmead Hospital and TL at Nepean Hospital. Data for all coded AMIs presenting to both hospitals between July 1998 and July 1999 were prospectively collected and the in-hospital outcomes reviewed (eligibility: age < 75 years (y), < 4 hours from chest pain onset and no previous CABG). Univariate and multivariate logistic regression analyses were performed. Results: One hundred and twelve patients satisfied the inclusion criteria with patients undergoing PPTCA at Westmead and, 60 patients receiving TL at Nepean. The PPTCA cohort was older than the TL cohort (mean ages 58~ and 53y respectively, ~~0.05). Both groups were well matched for all other vascular risk factors. The in-hospital mortality and non-fatal reinfarction rates were 1.9 and 3.8 percent respectively in the PPTCA group and, 1.7 and 16.7 percent in the TL group respectively (~~0.54 and 0.06 respectively). Emergency CABG was required in 3.8% of PPTCA patients vs. 6.7% of TL patients (p=O.S).ln a multivariate logistic regression analysis, primary angioplasty conferred a protective effect on the combined outcome of death or re-infarction compared with thrombolysis (relative risk 0.03; Cl 0.01,0.31; p < 0.01). Mean length of hospital stay was reduced in the PPTCA arm (6.8 YS X.3 days, p
Conclusions: Aortic stenosis progresses linearly at approximately 23%/year decrease in valve area. Patients under 50 years of age progress much more slowly than those over 50 years, suggesting degenerative calcific aortic stenosis may have a different natural history than congenital bicuspid disease. Implications for prevention of progression remain to be determined. OUTCOMES OF EARLY EXERCISE TESTING IN PATIENTS WITH MYOCARDIAL INFARCTION TREATED WITH PRIMARY ANGIOPLASTY. RP Zecchin’. G Lindsav. 1 Scotcher. YY Chai. 1 Huneerford. 1 Thelander. AR Denniss. Cardiology Department, Westmead Hospital, Sydney, Australia.

PREOPERATIVE TlROFlBAN IN PATIENTS UNDERGOING CORONARY ARTERY BYPASS SURGERY (CABG): SAFE USE lh’ A PRELIMINARY SERIES C.Manganas*. J.lliopoulos, T.C.Nolan, H.D.Wolfenden,

D.C.Newman. P.W.Grant, N.S.Jenson. Departments of Cardiology and Cardiothoracic Surgery, Prince of Wales Hospital, Sydney, Australia. BACKGROUND: Attempted plaque stabilisation in preoperative CABG patients with acute coronary syndrome (ACS) using abciximab (Reopro) has been associated with significant postoperative bleeding. The new small molecule IIbIIIa inhibitor tirofiban may be a safer option. We aim to demonstrate safe and efficacious tirotiban use in a preliminary series ofpatients. METHODS: A retrospective analysis was performed on twelve patients (8 male; 4 female) admitted with acute coronary syndrome and angiogmphically graftable coronary artery disease. All were commenced on intravenous tirofiban whilst awaiting urgent inpatient CABG on intravenous heparin, nitrates, and oral aspirin. Time between tirofiban commencement and surgery ranged from OS-7

days.

Tirofiban

infusion

was

ceased

four

hours

pre-

operatively. Postoperative blood product usage, blood drainage cardiac troponin I was recorded in all patients.

and

RESULTS: There were no deaths and all patients in this series were discharged home clinically well, without major postoperative complications. There were no re-explorations for bleeding, no

thrombocytopaenia required

blood

or platelet transfusions transfusions

(two

required fresh frozen plasma demonstrable hypersensitivity postoperative elevations ofcardiac

units

requited. each),

and

Two one

patients patient

(four units). There were no reactions. There were no tmponin I. CONCLUSIONS: Tirofiban administration in unstable preoperative CABG patients is safe and effective for cardiac stabilisation of this hieh risk eroun of oatients.

Exercise testing (ET), is a useful tool to risk stratify patients (pts) post acute myocardial infarction (AMI). Very little data is available observing outcomes associated with ET in pts who had a recent AMI, treated with primary angioplasty r stent (PA). Method: The study group comprised pts who had an AMI, treated by PA, and were referred for a maximal sign and/or symptom limited ET. Results: In all, 225 AM1 pts had PA in the period studied, with 126 AM1 pts (56%) having early ET. This group had an average age of 56 t llyrs, inferior infarction in 51%, LVEF was 50 c 12 % (range 17-72%), and 62 (49%) had single vessel disease. In all, 139 lesions were angioplastied with 123 stems being deployed. Risk factors were: diabetes (18%); smoking (56%); hypercholesteraemia (72%) family history (21%) and sedentary lifestyle (47%). ET was performed 9 + 11 days post AMI (median = 5, 71% pm-discharge) with 54% of pts being on betablockers. ET data analysed included treadmill time (6 + amins), METS (8 f 4 METS), percentage of predicted heart rate reached (85 f 14%), maximal heart rate (126 + 22 beats) and maximal systolic BP (152 + 34 mmHg). There were no acute adverse outcomes associated with early ET. ST segment >lmm and /or angina (positive ET) occurred in 28 pts at early ET of whom 21 (75%) had further surgical or medical intervention for disease in other vessels (n = 16) or restenosis (n = 5). This compares with an adverse event rate of 12% in the group with negative ET (p < 0.001). At a mean follow-up of 9 + 6 months (range l-24), there were 2 deaths (1.6% mortality), and restenosis of PA site was documented in 11 pts at repeat angiography and presumed in one of the patients who died (total restenosis rate = 9.5%) Conclusion: Exercise testing appears to be safe and effective in risk stratifying pts who need further intervention after AM1 treated by PA. Restenosis and mortality rates in this study appear relatively low.

Al

12

49th Annual

Scientific

Meeting

of CSANZ

COMPARISON OF AN IMMEDIATE INVASIVE STRATEGY IN SUSPECTED AM1 WITH AND WITHOUT ST SEGMENT ELEVATION. Y. Kovama*. P.S. Hansen. G.I.C. Nelson and H.H. Rasmussen. Royal North Shore Hospital, St. Leonards, NSW. Recommended management for suspected acute myocardial infarction (AMI) in patients with ST-elevation or new bundle branch block and patients with non-ST elevation acute coronary syndromes differs markedly. We have prospectively studied the outcome of the same immediate invasive strategy in consecutive patients with or without ST segment elevation. ST-elevation AM1 was defined as in GUSTO. Patients with non-ST elevation acute coronary syndromes were identified by symptoms, signs and electrocardiographic findings and by persistence of symptoms despite antiischaemic treatment for >20 min. A trial of treatment was discouraged with marked ST depression or haemodynamic instability. 248 patients, aged 31-93 years, had ST-elevation AMI and 104 patients, aged 31-94 years, had non-ST elevation acute coronary syndromes. Prevalence of hypertension, diabetes, hypercholesterolaemia, smoking and previous AM1 and by-pass surgery were similar. Killip Class III or IV on presentation was found in 7.6% with ST-elevation AM1 and 13.5% with non-ST elevation acute coronary syndromes. 74% and 68% had a flow-limiting coronary obstruction (TIM1 O-2). Immediate percutaneous coronary intervention was used in 76% of patients with ST-elevation AMI and 66% of patients with non-ST elevation acute coronary syndromes. TIM1 3 flow was restored with a mean delay from notification of the interventional team of 60 min and 67 min. By-pass surgery was performed during the same admission in 13 and 15%. The in-hospital mortality for all patients in the two groups was 3.2 and 5.8%. We conclude that the risk factor profile and prevalence of acutely flow-limiting coronary lesions are similar in ST elevation AM1 and a subset of patients with non-ST elevation acute coronary syndromes and persistent symptoms. Similar treatment strategies should be considered.

OUTCOMES INFARCTION HOSPITAL HOSPITAL. Department

OF PRIMARY ANGIOPLASTY FOR ACUTE MYOCARDIAL IN PATIENTS PRESENTING TO A TERTIARY CARE VERSUS THOSE TRANSFERRED FROM A DISTRICT E. Kizana*. l? Kovoor. M.l? Skinner, LB. Uther and D.L. Ross. of Cardiology, Westmead Hospital, Westmead NSW.

Primary angioplasty (PPTCA) has been shown to be superior to fibrinolytic therapy (FT) in patients with ST segment elevation acute myocardial infarction (STAMI). Whether patients presenting to hospitals without onsite FTCA benefit from transfer for PPTCA versus immediate ET is unknown. Since November 1999 four district hospitals (DHs) in the Western Sydney area have transferred (distance 10 to 32km) STAMI patients presenting within working hours (0730 to 1530) for PPTCA according to a previously implemented PPTCA protocol (chest pain < 4 hours, age < 75 years, no cardiogenic shock and no prior coronary artery bypass grafts (CABG)). At the end of January 2001 a total of 28 STAMI patients were transferred from DHs for PPTCA. During this same time period PPTCA was performed (24 hour basis) on 76 STAMI patients who presented directly to Westmead hospital (WMH). RESULTS

DIRECX TO WMH TRANSFER FROM DH 76 28 56 56 76 68 43 / 41 / 16 64 / 21 / 15 111 180 95 96 86 / 80 82 / 75 95 96 52 50 Death 1 1 IRA = infarct related artery, RCA = right coronary artery, LAD = left anterior descending artery, TIM13 = TIMI grade 3 flow, LVEF = left ventricle ejection fraction.

Patients (n) Mean age (years) Male (%) IRA - RCA / LAD / other (%) Mean Door to TIM13 time (mins) TIM13 achieved (%) Stent / Abciximab usage (%) Successful I’PTCA (%) Mean radionuclide LVEF (%)

ln the DH group there was one failed PTCA due to vessel dissection with late death due to cardiogenic shock and multiorgan failure, and one repeat PTCA for acute closure. In the WMH group there were 4 failed PTCAs (IRA could not be wired, IRA with
Heart,

Lung

and Circulation

2001; 10

LOCAL PLATELET ACTIVATION DURING INFARCT ANGIOPLASTY DESPITE ADJUVANT ABCIXlMAB THERAPY Andrew J. Tavlor*. Alex Bobik. Michael C. Berndt. and Garw Jennings. Baker Medical Research Institute and Alfed and Baker Medical Unit, Alfred Hospital. Melbourne, Australia. BACKGROUND: Platelet activation is elevated in acute coronary syndromes, including acute myocardial infarction (AMI). The use of Abcixmab in conjunction with angioplasty for the treatment of AM1 improves clinical outcomes, however its effect on local platelet activation at the culprit lesion site is unknown. METHODS: Coronary sinus (CS) blood was sampled from patients undergoing angioplasty combined with Abciximab for AM1 (n=9), and from a group with stable coronary artery disease undergoing elective angioplasty without Abciximah (n=9). Platelet activation was assessed by the percentage of platelet surface expression of CD62P (P-selectin), and PACl (activated IIb/IIIa receptor). Peripheral blood was also drawn from AM1 patients to compare peripheral levels of platelet activation with coronary sinus levels. RESULTS: The percentage of platelets activated in CS blood post angioplasty was not significantly different between patients with AM1 treated with Abciximah and those patients with stable coronary artery disease (P-selectin positive cells 12.02 f 4.21% versus 9.82 f 3.06%, P=NS). In AM1 patients, however, the levels ofplatelet activation measured by P-selectin were significantly higher in CS blood than in peripheral blood (12.02f4.21%versus6.11f 1.06%,P=O.Ol).BindingofPACl toplatelets was extremely low in all patients with AM1 treated with Abciximab (mean PAC-1 positive cells in CS blood 0.44 + 0.13%). CONCLUSIONS: The level of platelet activation of patients treated with infarct angioplasty and Abciximab is similar to those with stable coronary artery disease. The presence of a gradient of platelet activation during AM1 between CS and peripheral blood, however, suggests that local platelet activation still occurs at the culprit lesion site.

TRICUSPID REGURGITATION PROMOTES BILIARY EPITHELIAL INJURY IN HEART FAILURE. G.Lau*l, H.TanZ, LKritharides2, ‘“Department of Cardiology, Concord Hospital, NSW Australia 2139. 2Department of Cardiology, Changhi Hospital, Singapore. 3Heart Research Institute, NSW Australia.

Background:

Hepatopathy

is a recognised

complication

of cardiac

failure.

However, the incidence and profile of liver enzyme abnormalities, the implications for pathogenesis and the causative role of individual cardiac factors are unknown. We hypothesised that tricuspid regurgitation (TR) and right atial pressure (RAP), as key determinants of reverse flow in the Inferior Vena Cava (IVC) and Hepatic vein, are important mediators of hepatic injury in cardiac failure Methods: The records of all Cardiology inpatients with a Diagnosis Related Group (DRG) of heart failure admitted over an 8 month period were analysed. Of these there were 57 patients (35 men and 22 women aged 41-91 years old, NHYA functional class II to IV) with concurrent transthoracic echocardiographic studies (TTE) and liver function tests (LFT), but without confounding causes of raised LFT. All patients had alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) measured. Videotapes of all ‘lTE were analysed by two blinded observers for left ventricular ejection fraction (LVEF), right ventricular-right atria1 pressure difference (RV-RA), severity of tricuspid regurgitation (TR) and right atria1 pressure (RAP). For analyses, elevation of LFI was defined as 1.5 times the upper limit of normal and TIE were grouped according to abnormal LVEF (<=30% or >30%), severity of TR (none/mild or moderate/severe), RV-RA (<=40 or >40 mmHg) and, where possible, absence or presence of elevated RAP (defined as non-collapsing and dilated IVC). Results: Of the 57 patients, 19% had elevated GGT, 5% elevated ALP, 2% elevated ALT and 0% elevated AST. There was no apparent relationship between GGT and abnormal LVEF or elevated RV-RA. However, the relative risk (RR) of elevated GGT was 4.2-fold (95% CI 1.7-10.5) in those with moderate/severe TR compared to those with trivial/mild TR. In the 35 TTE studies where RAP could be accurately assessed, those with elevated RAP had a 2.9-fold RR (95% CI 1.1-7.7) of elevated GGT compared to those with lower RAP. by biliary epitheConclusion: Elevation of plasma GGT, which is synthesised lium, is more typical of cardiac failure than elevation of other LFT, and is related to severity of TR and elevated RAP.

Heart,

Lung

and Circulation

2001;

10

EXTENSION OF A COMPREHENSIVE MANAGEMENT PROGRAM FOR HEART FAILURE FROM THE OUTPATIENT TO THE INPATIENT SETTING L Macfarlane*, M Richardson. D M Kave. H Krum. P 1 [email protected] Alfred Hospital, Prahran, Australia Background: The Alfred Hospital, a 380 bed tertiary referral centre with a heart transplant service, established a Heart Failure (HF) Unit in 1997. A nurse practioner coordinates a multidisciplinary team with 6 HF cardiologists, to deliver a comprehensive management program (CMP) for patients including a tailored exercise program. At 6 months follow-up after starting CMP there was an 86% reduction in rehospitalisation and improved NYHA status. A drawback of the program is its restriction to outpatients specifically referred to the HF Unit. On this basis, a HF coordinator for inpatients (in-pts) was appointed in 1999 with the goal of extending CMP to include pts with HF admitted to all medical units including pts with significant comorbidities. A randomised controlled trial to evaluate the program is currently in progress. Aims: 1. To establish a CMP for in-pts, providing education and guidelines for self management of HF including pts from non-English speaking backgrounds. 2. Co-ordinate a discharge plan including titration of medication. 3. Provide HF education to healthcare workers. Methods: 1. Establishment of a HF database for all in-p& 2. Assessment of all pts to identify those suitable for CMl? 3. Intensive education of pt and family re fluid, salt, diet and lifestyle management, medications, daily weight, symptoms of worsening HE Education , written guidelines and a diary are provided in the pts preferred language. 4. Provision of an emergency action plan. 5. Referral to community services and exercise program for suitable pts. 6. HF education for nursing staff and other carers, including in nursing homes. Results: From Mar-Dee 2000,250 consecutive pts were assessed of whom 181 (72%) were suitable for CMP. Of these, 64% were males. Mean age for males was 58(23-88), females 73(20-91) (p
EXERCISE TRAINING IMPROVES ENDOTHELIAL FUNCTION AND INCREASES ARGININE TRANSPORT IN CONGESTIVE HEART FAILURE PATIENTS. Parnell MM*. Holst Dl? Starr 1. Chin-Dustine IPE Kave DM. Alfred Heart Centre and Alfred Baker Medical Unit, Baker Medical Research Institute, Melbourne, Victoria. Reduced endothelial function is a common finding in congestive heart failure (CHF), however the mechanism behind this dysfunction remains uncertain. We have recently reported a decrease in the clearance of L-Arginine, the precursor for nitric oxide synthesis, from the forearm circulation of CHF patients, suggesting this may be the rate-limiting factor leading to endothelial dysfunction in this patient group. Given data that show exercise training increases endothelial function in CHF patients, we aimed to investigate whether these improvements were due to an increase in arginine transport. Eight male CHF patients (NYHA class II-III) have completed the study to date, 5 patients enrolled in the 8 week exercise program and 3 continued with their usual lifestyle. Measures of arginine transport, endothelial function and exercise capacity were repeated before and after the eight week study period. After 40 minutes of 3H-L-Arginine infusion (6pCi/hr) to determine arginine transport, infusions of ACh (9.25 and 37 pg/min), SNP (2 and 8 pg/min) and L-NMMA (4 pg/min) were performed. Forearm blood flow (FBF) was measured before and after two minutes of each drug infusion, and venous blood samples were obtained for the calculation of arginine clearance, Exercise capacity (6 minute walk test) increased following involvement in the exercise program (489 ? 26 to 555 + 18 metres; p=O.O2) while the control group demonstrated no change (505 t 27 to 510 ? 41 metres; p=ns). Basal FBF did not change following exercise training (21 + 3 to 22 t 4 ml/min; p=ns) or usual living (15 + 3 to 19 t 3 ml/min; p=ns). Forearm blood flow responses to acetylcholine increased following exercise (mean area under curve pre exercise vs. post exercise: 1244 + 234 vs. 2439 f 603 units; p=O.O4) demonstrating an improvement in endothelial function. The basal clearance of arginine was significantly increased following involvement in the exercise program (79.1 r 6.5 to 116.0 + 806 ml/min; p=O.O06) while there was no change in the control group (66.5 + 20.1 to 77.5 + 16.4 ml/min; p=ns), The improvement in endothelial function observed following exercise may be due to an improvement in the transport of arginine in congestive heart failure patients.

49th Annual

Scientific

Meeting

of CSANZ

A113

INSULIN RESISTANCE IN CHRONIC HEART FAILURE: LABORATORY AND CLINICAL MEASUREMENTS. WA Parsonaee’. AT Evans. D Hetmanski &Al Cowlek University Hospital, Nottingham, United Kingdom Background: Chronic heart failure (CHF) is a syndrome of cardiac abnormality accompanied by a characteristic neurohormonal response. Insulin resistance has been recognised as an element of this neurohormonal response, but there have been limited attempts to quantify it. Insulin resistance and hyperinsulinaemia may be linked to, and contribute to, several aspects of the pa&physiology of CHF including regional haemodynamic abnormalities, endothelial dysfunction and skeletal muscle abnormalities. We aimed to quantify insulin resistance in patients with heart failure and observe the consequent compensatory hyperinsulinaemia in a postprandial setting. Two experiments were performed. Experiment 1: Ten male patients with CHF and nine healthy age matched controls took part. Insulin resistance was quantified using the hyperinsulinaemic euglycaemic clamp technique to measure whole body glucose metabolism (M). M was measured at steady state during continuous infusions of 40 and 100mU/m2/min whilst maintaining euglycaemia with a variable infusion of 20% glucose. M values and the area under the M value curve were analysed using the unpaired t test. Experiment 2: Ten male patients with CHF and ten matched controls attended the laboratory on two occasions. Subjects attended in a fasting state and baseline blood samples were taken. Subjects then ate a 2.5MJ meal that on one occasion was high in carbohydrate (75%) and on the other high in fat (71%). The order of the visits was random. Serial blood samples for blood glucose and plasma insulin were taken until 180 mins after the meal. Results are expressed as meankstandard error and postprandial insulin and glucose curves were analysed using a repeated measures ANOVA. Results: During the 40mU/m2/min insulin infusion M was significantly lower in patients than controls, 3.7kO.7 vs 6.1~0.8mglkglmin(p<0.05). The area under the dose response curve for the insulin infusions was also lower in the patients than controls, 7.57iO.94 vs 10.71+0.92 units (~~0.05). There was a significant hyperinsulinaemic response to the high carbohydrate meal in the patients (ANOVA p
CHRONIC CLOZAPINE ASSOCIATED TACHYCARDIA IS NOT ASSOCIATED WITH CLOZAPINE CARDIOMYOPATHY. D.Rees*. D. Ramsau, l? Davidson. Department of Cardiology, St George Hospital, Sydney, Australia Cloaapine is effective for refractory schizophrenia, however chronic use may be complicated by agranulocytosis, weight gain, lipid abnormalities, tachycardia and reports of myocarditis, cardiomyopathy and sudden death. A cohort of 33 subjects receiving clozapine was studied to determine the relationship between clozapine induced tachycardia and clozapine cardiomyopathy. The average age was 33+9 years, 79% were male and the duration of clozapine therapy was 1123 months (average daily dose of 444+228mg). There was a high rate of active smoking (61%), but lower rates of hypercholesterolaemia (9%), diabetes (3%) and hypertension (15%). The average heart rate was elevated at 102*13 bpm, with a corrected QT interval within the normal range (395+22msec for males, 411+21 msec for females). The average LVEF assessed by echocardiographic techniques was normal (65*12%, normal range 55.70%). No cases of clozapine cardiomyopathy or sudden death were identified in 12 months follow up, although one case each of ischaemic cardiomyopathy, alcoholic cardiomyopathy and severe aortic stenosis were newly diagnosed. The results suggest that clozapine induced tachycardia is well tolerated and related to the anticholinergic effects of the drug and does not have an important rate mediated mechanistic role in cloaapine induced cardiomyopathy, Cardiac review remains important in this subgroup however to identify rare idiosyncratic cases of myocarditis and cardiomyopathy. Screening is further supported by the high incidence of non clozapine related serious cardiac diseases and adverse risk factors in this socially isolated young population.

A114

49th Annual

Scientific

Meeting

of CSANZ

Heart,

DRAMATIC EFFECT OF CARDVEDILOL IN PATIENTS TREATED FOR LEFT VENTRICULAR DYSFUNCTION - INTERMEDIATE FOLLOW-UP W Parsonage*, AGalbraith, G M Scalia The Prince Charles Hospital & Queensland Heart Clinic, Wesley Hospital, Brisbane AUSTRALIA Background. Beta-blocker therapy with carvedilol has been shown to have benefits in hard endpoints such as death and re-admission for heart failure. Data on intermediate term individual ejection fraction response. is variable between studies. Predictors of benefit remain to be demonstrated. Patients. Serial follow up of selected patients with idiopathic cardiomyopathy on maximal conventional therapy for a period of 1 to 2 years prior to carvedilol therapy and then for l-2 years on betablockers was obtained by echocardiography and clinical review. Drug, therapy, demographic and ventricular function data were reviewed. 28 pts aged 51*14yrs were studied prior to (PreBB #l&PreBB#2) and following betablocker institution at approximately 1 yr (Post BB #l) and 2yrs (Post BB #2). Individual pt ejection fraction (EF) data is displayed (left panel) with group mean value (bold line). Overall EF rose from 26i7% to 40+12% (plO% at final follow-up) vs Nonresponders, it was seen that responders had significantly lower EF at baseline than non-responders (22.9% vs 29%, p=O.O45) - see right panel. This suggests that pts with the most severely reduced EF at baseline benefit at least as much as those with milder dysfunction. There was a trend towards reduced LV diastolic volume across all pts.

Lung

and Circulation

2001; 10

EFFECT OF EXERCISE ON CENTRAL HAEMODYNAMICS IN SEVERE HEART FAILURE. C. Cheetham’. T.G. O’Driscoll. B. Bastiaans, R.R. Tavlor, L Dembo. D.T. GreenCardiac Transplant Unit and Cardiology Department, Royal Perth Hospital, Human Movement and Medicine, The University of WA and WA Heart Research Institute. Introduction: Exercise is now considered an important component of management in severe heart failure (HF). However, little is know about the central haemodynamic changes which occur during different modalities of exercise in severe LV dysfunction. This study investigated the effect of aerobic and weight resistance exercise on central haemodynamics. Methods: Seventeen subjects (LV ejection fraction of 25+2 Yo) undertook brachial artery and right heart catheterisation and assessment of oxygen consumption (VO,), at rest and during submaximal and peak recumbent cycling (RC) and submaximal (40% max) upper (UL) and lower limb (LL) weight resistance exercise. Student’s paired t-tests were performed to assess statistical difference between baseline and exercise data and between different exercise modalities. Results: Sub-max RC, UL and LL exercise were performed at 52,39 and 25% of VO eak, respectively. Cardiac output (CO) increased during peak RC (PcO.0 sp) but did not significantly change during sub-max RC, UL or LL exercise relative to baseline. CO during peak RC differed significantly to that during UL and LL (P
CVP were 0

i -Non-Rsspm*m m.a.n

-II

m”Esn

mdmv.2

m.enn

j,nsrsssed -e

PMIWII

EF SIOI)

~ PMll l

Conclusions: Carvedilol significantly increases ejection fraction by a clinically important increment in a selected subgroup of patients treated for idiopathic cardiomyopathy. Very poor ejection fraction at baseline does not adversely influence this benefit.

reduced

higher

during

than

during

LL, sub-max

UL exercise and peak

(P
RC (p
LV stroke

work

index

but did not change

dur-

ing UL exercise, resulting in a difference between RC and LL compared to UL exercise (P
UL exercise (l’
during

CO. Compared

exercise

must

be met by increased

viduals, patients with HF appear to increase CO, with SV declining

to be more dependent during all modalities

with

healthy

upon increases of exercise.

indiin HR

CHANGES IN NONINVASIVE BIOIMPEDANCE HAEMODYNAMICS AFTER EXERCISE IN ADVAVNCED HEART FAILURE. BP Sindone*?? PM DaBendeicht.T Yeoht.1 Dal9.D Elliott~. Department ofCardiology.Concord Hospitalt, NSW: Deparlment of Cardiology, St George Hospital’. Kogarah. NSW. Faculty of Health. University of WesErn Sydney#NSW. Faculty of Nursing. University of Sydney1 NSW.

ALTERNATIVE WAYS TO REDUCE HOSPITAL READMISSIONS IN HEART FAILURE: PRELIMINARY RESULTS OF THE PHIRE (Predischarge Hospital Intervention Readmission Evaluation) STUDY.-

Haemodynamic abnormalities may predict symptoms and prognosis in heart failure and guide therapy Patients with heart failiure who do not increase their cardiac output with

Heart failure patients frequently requireaeadmission IO hospital within the first year after discharge. A predischarge nursing consultation followed by a home visit one week post-discharge has been shown 10 reduce lhis readmission rate and improve outcomes. We evaluated the effect of an intensive nursing intervention alone 10 assess whether this leads to improved outcomes in heart fail& patients. METHODS: All patienls admitted to a tertiary referral cardiology unil diagonosed wich heart failure over a 6 month period were randomised to an Intensive nursing intervention (Nl) prior to discharge or control (c). The nursing intervention included: education. information on fluid and salt restriction.daily weighing, symptoms and signs of deterioration. instmction on their medication/compliance. follow-up and what to do if they fell unwell. An information package was provided and carers were also involved. They were then followed-up for a mean of 6 monlhts to evaluate their outcomes. Enrolment and followup is currently ongoing. RESULTS: There were 134patients admitted with heart failure over 9 months. Mean age 74f10 years, 70% male, New York Heart Association Class 2.9fo.8 and left ventricular ejection fraction 0.32+0.14 (50% ischaemic heart failure) Of the 91 patients. 18had been admitted for heart failure a total of 23 times in the preViOUS year. Mean lenglh of stay was 11.7f13.5 days. There was no significant difference in baseline characteristics of NI and C patients 69 patients were randomised to C and 65 to Nl. Of the64 NI patients. 47 did nol participate due to: no English and no carer who spoke English - 7. confusion/dementia - 9. refused - 11.died before discharge 4. discharged before they could he interviewed 7. Nursing Home residents (not in control of their medicatio&fluid/salt intake, etc). 8. This left 18padents in Ihe Nl group. In followem the C natients had 53 readmissions (mean 0.75f1.3: 15% heart fallme. 46% other -r.-~rcardiac causes and 39% non-cardiac) whilst the NI patients had ZOreadmissions (mean l.lfl.7: 40% heart failure. 20% other cardiac causes and 40% non-cardiac this was influenced by 2patients who had 5 readmissions each). subsequent death occurred in 11% of both the C and Nl patients. ‘Ihere was no significant difference in outcomes between now% CONCLUSIONS: In this preliminary analysis, an intensive nursing h;ltekemion did not significantly influ&e the subsequent readmission or mortality rate However this mav have been due to the small number of patients in the intervention group. a few patie& with multiplereadmissionr and the high proportion who withdrew or were ineligible for Ihe nursing intervention. This study is continuing. to try to assess whether there is any benefit from a pre-discharge intervention alone. or whether home visits are necessary, in addition to apre.discharge visit (as previously shown to be effective). to achieve a reduction in thereadmission rate and improved outcomes in patients admitted to hospital with heart failure

&ercise mai not tolerate exercise training, may derive less benefit and have a worse oraenosis than those who augment their cardiac outnut We measured the exercise

bae;cdynamics

of patients at&ding

a HeaR Failure Cli& via noninvasivebioimpedance

to assess theircardiovascularresponse to exercise and their suitability for exercise uaining METHODS: Studied 41 patients. age 68f10 years. 85% male. left ventricular (LV) ejection fraction 0.24iO.I 1 units. New York Heart Association class 2.7M.8 units with advanced heart failure. Before and immediatelv after a 6.minute walk tests they underwent noninvasive biolmpedance haemcdyna& studies RESULTS: HAEMODYNAMIC VARIABLE REST POST-EX CHANGE HEART RATE (bentslmin) 75f16 8.70% 69fl3 I 00% BLOOD PRESSURE (mmHg) 97*17 9ie24 CARDIAC OUTPUT (Urnlo) 4.7f1.7 5.3i1.7 12.80% SYSTEMIC RESISTANCE 1494f674 14423~803 -3.50% VACULAR (dynes/em/see-5) STROKE VOLUME (ml&eat) 70.2f23.9 72 7125.0 3.60% 32.0f6.9 32.7f6.7 2.20% THORACIC FLUID CONTENT (ml) 16.70% LEFT CARDIAC WORK (kg/mlo) 4.8f2 0 5.612.6 ACCELERATION INDEX (/lo0 aec2) 84.7f32.3 95.8zt39.1 13.10% 44.7f18.2 49.Sf21.0 10.70% VELOCITY INDEX (11000 see) -8.20% SYSTOLIC TIME RATIO (units) 0.49iO.17 0.45f0.16 -9.90% PRE-EJECTION PERIOD (msec) 131f32 118i.27 LV FJECTION TIME (msec) 284541 282*38 -0.70%

CONCLUSIONS: Hearlfallurepatients only modestly augmenttheircardlac output after submaximal exercise. Tins may be because the level of exertion is patient limited This is suggested by Ihe small change in heart rate. blood pressure and stroke volume. The increase in left cardiac work. acceleration index and velocity index may reflect some ability to increase cardiac performance with exercise but may be contributed to by a reduction in systemic vascular resistance and concomitant medications. Such an assessment may be useful in evaluating heart failure patients

Bendeich.HSPWon&Hean Concord, NSW.

Failure Unit, Department of Cardiology, Concord Hospital.

Heart, Lung and Circulation

2001; 10

AN ECONOMIC ANALYSIS OF AGEMENT IN THE UK - CAN S. Stewart*, L. Blue, A. Walker, C.E. Failure, University of Glasgow and Scotland.

SPECIALIST HEART FAILURE MANWE AFFORD NOT IMPLEMENT IT? Morrison and J.J. McMurray CRI in Heart Greater Glasgow Health Board, Glasgow,

49th Annual Scientific Meeting of CSANZ

All.5

INCREASED EXPRESSION OF UROTENSIN II AND ITS RECEPTOR IN AN EXPERIMENTAL MODEL OF LEFT VENTRICULAR MYOCARDIAL INFARCTION IN THE RAT: IMPLICATIONS IN ADVERSE CARDIAC REMODELING. A. Tzanidi$*.*HaManZ.z, Dane Onanzz D.mlHKruml. ‘Clinical Pharmacology Unit, Department of Medicine, Monash Medical School, *Baker Medical Research Institute, Alfred Hospital, Melbourne, Australia

Background: As hospital activity represents the major cost component of health care expenditure related to heart failure (HF), this study evaluated the economic consequences of applying specialist nurse management programmes designed to limit HF-related hospital m-admissions, on a UK-wide basis. Methods: Using a model of the current level and cost HF-related hospital activity in the UK, we examined the specific thresholds at which the actual cost of applying three different models of specialist nurse management of HF for patients following hospital discharge would be equal to the ‘economic cost’ of bed utilisation associated with preventable hospital readmissions. Three programmes of HF management were examined - home-based, cliiicbased and a combination of home plus clinic-based follow-up. In this analysis it was estimated that a caseload of up to 122,000 HF patients discharged from UK hospitals in the year 2000 would be generated. Results: We estimated that 47,000 of these 122,000 patients would normally accumulate a total of 594,000 days of associated hospital stay from 49,000 readmissions (for any reason) within one year of hospital discharge. The economic cost of these hospitalisations to the National Health Service in the UK was calculated to be E166.2 million. A 10% reduction in associated bed utilisation would be associated with a total of E18.0 million health care expenditure being available for other purposes once associated outpatient and general practice resources are taken into account. The cost of applying a UK-wide programme of home-, clinic- and home plus clinic-based follow-up would be E69.4, E73.1 and E72.5 million per annum, respectively. The relative thresholds at which the economic savings associated with reduced bed-utilisation for recurrent hospitalisation would equal the cost of applying these programmes would be 38.5%, 40.6% and 40.3%, respectively. If, as suggested by randomised trials, a home-based programme of specialist nurse management reduced such bed utilisation by at least 50%, annual economic savings equivalent to E169,OOO per 1000 patients treated would be generated. Conclusions: This is the first study to examine the economic consequences of applying a specialist nurse-mediated, post-discharge management programme for HF within a whole country. It shows that such programmes not only have the potential to improve quality of life, reduce hospital readmissions and prolong survival, but also release resources to increase the efficiency of the health care system. These data provide a strong economic argument for the widespread implementation of this type of intervention.

Urotensin II (UII) has been identified as the most potent human vasoconstrictor peptide (Ames et al, Nature, 1999), being up to 28-fold more potent than endothelin-1. We have previously demonstrated that UII has additional nonhaemodynamic effects on the myocardium that are characteristic of adverse cardiac remodeling, such as stimulation of matrix synthesis by cardiac fibroblasts. In this study, we examined whether there is local activation of the UII system in pathological cardiac remodeling using an experimental animal model of left ventricular dysfunction post-myocardial infarction (MI). Female SD rats underwent ligation of the left anterior descending coronary artery (MI) and the heart excised at week 1 following surgery for immunohistochemical localization of UII peptide and quantitation of UII receptor (UIIR) mRNA transcript by nuclease protection analysis. Sham operated animals served as controls. As seen in normal rat myocardium, UII peptide in sham control animals was immunolocalised predominantly to the vasculature. In contrast, LVMI rats demonstrated increased expression of UII peptide throughout the infarct and non-infarct regions, particularly in areas of interstitial collagen deposition and fibrosis. This increase in peptide expression was paralleled by a significant upregulation of UIIR mRNA transcript by 80+_11% in comparison to sham controls (P
INCIDENCE AND NATURAL HISTORY OF HEART FAILURE IN 15,406 MEN AND WOMEN - THE RENFREW/PAISLEY STUDY. S. C.L. CRl in Heart Failure and Department of Public Health, University of Glasgow, Glasgow, Scotland.

MORTALITY AND HOSPITAL ADMISSIONS FROM HEART IN NEW ZEALAND ETHNIC GROUPS. S P Wrigwy G Gamble. N Sharpe. Dept of Medicine, University of Auckland

Background: There are few population-based, longitudinal studies of the incidence and predictors of heart failure (HF). Furthermore, there is a paucity of data to describe its “natural history”. We describe the incidence, baseline predictors, natural history and consequences of heart failure in one of the largest epidemiological studies ever undertaken. Methods: The Renfrew/Paisley Study originally surveyed persons aged 45-64 years living in these two towns in the West of Scotland. Approximately 80% of the target population (7,052 men and 8,354 women) was subject to a comprehensive screening programme between 1972-1976. Using the unique Scottish Morbidity Record Scheme with record linkage to the Register General Office in Scotland, all subsequent hospitalisations and deaths (and their attributable cause) 20 years thereafter were documented. Results: During 20 years of follow-up a total of 333 men (4.7%) and 300 women (3.6%) were hospitalised at least once with HF. In men, the number of incident HF hospitalisations increased from 157 to 468 per 100,000 personyears of follow-up in those initially aged 45-49 years and 60-64 years, respectively. In women the equivalent figures were 96 and 390 per 100,000 person-years. Independent baseline predictors of HF hospitalization in the 5-20 years following screening (P < 0.05 for all variables) were age (RR 1.08 for each additional year), male sex (RR 1.52), history of smoking (RR 1.36), chest pain (RR 1.35), stroke (RR 2.92), radiographic cardiomegaly (RR 1.62), left bundle branch block (RR 2.18), atria1 fibrillation (RR 2.80), systolic BP (RR 1.28 per 10 mmHg increase), adjusted FEVl (RR 1.33 per 10% decrease), body mass index (RR 1.09 per 5 kg/m2 increase) and hyperglycemia (RR 1.68). In both men and women and in all age groups incident HF hospitalisation represented over 50% of the first major cardiovascular events recorded. Among the 44% of men and 42% of women who experienced another cardiovascular event preceding HF, AMI was the most common diagnosis. Overall, both men and women who were hospitalised with HF had a greater than 2.5 and 3.0-fold adjusted risk of all-cause death compared to remainder of the cohort. Conclusions: Consistent with previous reports, we found the population incidence of HF is both large and increases with age. Most significantly, using a unique form of follow-up, we also found that almost 60% of men and women who experience a HF hospitalization do so as their first major cardiovascular event. Furthermore, the life expectancy of such individuals is dramatically shortened.

FAILURE

Background: Heart failure (HF) is a major public health problem, characterised by frequent hospitalisation and a poor prognosis. This study examines hospital admissions and mortality of HF patients of Maori, Pacific Island (PI) and non-Maori/non-PI ethnicity over 10 years with HF in New Zealand. The study used a national hospital admissions database from 1988 to 1997. Methods: National statistics for hospital admissions with HF were obtained from the New Zealand Health Information Service from 1988 to 1997 inclusive. Cases were selected using ICD-9 codes for HF both as a primary diagnosis or a secondary diagnosis associated with either ischaemic, rheumatic or valvular heart disease. Admissions, mortality and mean length of hospital stay were calculated. Kaplan-Meir survival analyses were performed. Life expectancy in different ethnic groups was obtained from census data. Results: There were 91,540 admissions with HF over the decade 1988 to 1997, of which 10,809 (11.8%) admissions were of Maori patients and 2666 (2.9%) admissions were of patients of Pacific Island ethnicity. Total admissions increased by 50% between 1988 and 1997, while length of stay (LOS) for the total sample halved from 14 days to 7. The mean age at admission was significantly less for Maori (60.2 years) and Pacific Island patients (59.2 years) compared with non-Maori/non-PI patients (74.4 years), p
A116

49th

Annual

Scientific

Meeting

of CSANZ

Heart,

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THE DIFFICULTY OF HEART FAILURE DIAGNOSIS IN THE COMMUNITY. S P Wrieht*. A Pearl.‘GGable f h R N DOUP-hty Department of Medicine, +Depar$ent of General Practice and Primary Health Care, University of Auckland, Auckland, New Zealand.

LONG TERM FOLLOW-UP OF PATIENTS POST FONTAN OPERATION. 1 G Morean*. 1 L Wilkinson and L E Griev. Department of Cardiology, Royal Melbourne Hospital, Victoria

Background: Patients with heart failure (HF) frequently present to primary care. Diagnosis in primary care can be difficult, resulting in inaccurate diagnosis and inappropriate treatment. This study examines the accuracy of primary care diagnosis in a cohort of patients with symptoms suggestive of HF referred to a HF study. Methods: Patients aged >45 years with dyspnoea and/or ankle swelling referred to a study of the community diagnosis of HF were included. Each patient was seen within a few days of presentation, and underwent clinical history and examination, ECG, echo and chest radiography in a HF clinic. Each patient’s clinical data and investigations were reviewed by a panel of three cardiologists and one general physician who decided whether HF was present or not using European Society of Cardiology criteria. The diagnostic agreement of each referring GP’s diagnosis was compared to that of the panel. Sensitivity, specificity and other frequentist parameters were calculated. Results: Patients were referred from a network of 158 general practitioners (GPs) in central Auckland, with a median of 20 years practice experience (range 5 to 36). 44% of Gl’s were male, 14% solo practitioners; GPs worked a median of 9 FTEs (range 1 to 11). 91 patients were included, median age 71 years, 59% female. 38 (41%) patients presented with dyspnoea alone, 17 (19%) with oedema alone, and 36 (40%) with both symptoms. Using the panel diagnostic decision as a gold standard, 28 (31%) patients in the cohort had HF and 63 (69%) did not. The initial decision from the referring Gl’s was that 61 patients (67%) had HF and 30 (33%) did not. The initial decision from the referring GE’s was that 61 patients (67%) had HF and 30 (33%) did not. When compared with the panel, the likelihood ratio (LR) of a GP diagnosis of HF was 1.56 (95% CIs 1.21, 2.00). The LR of the GP excluding HF was 4.00 (95% CIs 1.32, 12.1). The sensitivity of the primary care diagnosis was 0.89 (95% CIs 0.72, 0.98), the specificity 0.43 (0.30, 0.56), positive redictive value 0.41 (95% CIs 0.29,0.54), negative predictive value 0.90 (95% P Is 0.73,0.98). Conclusion: This study shows that the clinical syndrome of HF is difficult to diagnose in the community on clinical grounds alone. Gl’s appear to overdiagnose HF, which may result in unnecessary treatment. The potential impact of strategies such as natriuretic peptide measurement and open access echocardiography on the accuracy of community diagnosis of heart failure warrants further study.

Background: The Fontan operation was first performed in 1971 with very good early results. Concerns have been raised about long-term complications, especially those occuring after 10 years. Aim: To assess the long-term outcome after the Fontan operation with respect to the prevalence of complications and the duration of complication free survival post Fontan. Methods: 24 patients who have had a Fontan operation and are over the age of 18 years are managed in our Adult Cardiac Congenital Clinic. This group of patients comprise our study group and these patients’ records were reviewed for the purposes of this study. Results: Of the 24 patients, 11 had double inlet left ventricle, 5 double outlet right ventricle, 6 tricuspid atresia and 2 other diagnoses. The mean age at Fontan operation was 10.6 years (4-33). The mean duration of follow-up was 15.4 years (8-20). 22 patients had atrio-pulmonary connection, 2 had an RA to RV conduit and 1 patient underwent a redo Fontan with an extra-cardiac conduit. The most frequent complication was atria1 re-entry tachycardia (ART) occurring ln 14 of our patients (58%) at a mean duration post Fontan of 10.2 years (3-18). Recurrences are common (12 of 14) (86%). Radiofrequency ablation (RFA) was used with limited success in 4 patients, 2 with clinical improvement but all having recurrent arrhythmias. Other complications were heart block requiring permanent pacing in 4 patients (17%), protein losing enteropathy (PLE) in 1 patient (4%) and a hypokalaemic cardiac arrest in 1 patient. Two patients have died, one drowning (?arrhythmia) 14 years postop and a second with a saddle pulmonary embolus while on warfarin, 12 years post Fontan. 1 patient had an uncomplicated pregnancy and 4 (17%) have severe ventricular dysfunction with 1 patient on the waiting list for heart transplantation. Post Fontan 83%, 61% and 38% of patients were complication free at 5,lO and 15 years respectively Conclusions: Complications are common post Fontan operation, the most frequently encountered being ART which tends to be recurrent and presents late post op. Other complications seen less frequently include pulmonary embolus, PLE and late occurrence of ventricular dysfunction.

THE ACCURACY OF BEDSIDE BNP MEASUREMENT USING A POINTOF-CARE METER. S P Wrieht+, G Gamble, I Pornfret. S Muncaster, S FisherAL T Yandle+, M Richards’. N Sharoe and R N [email protected] Dept of Medicine, University of Auckland, ‘Cardioendocrine Research Group, Christchurch School of Medicine, University of Otago Background: Brain natriuretic peptide (BNP) is emerging as a useful tool in the diagnosis of patients with heart failure (HF). Both whole BNP32 and the cleaved N-terminal traction can be used for HF diagnosis. Point-of-care BNP measurement devices are now available, but the accuracy of such instruments compared to established laboratory-based assays has not previously been investigated. This study compares the agreement of an established laboratory assay with the newly available BiositeB [email protected] BNP system, designed for point-of-care use at the bedside in a group of patients with possible HF. Methods: The patients in this study were a cohort of patients enrolled in a community-based diagnosis of HF study. Patients with dyspnoea and/or ankle oedema were referred to the study from a network of 158 general practitioners in central Auckland. Patients attended a HF diagnosis clinic where blood was collected ln EDTA, centrifuged, frozen at -8O”C, then sent for N-terminal BNP analysis, performed by the Christchurch Cardioendocrine Research Group. Point-of-care BNI’32 analysis, using the BiositeB TriageB BNP system, was performed immediately using lml of whole venous blood in EDTA. The agreement of the two assay techniques was assessed using Spearman ranked correlation techniques. Results: 81 patients were included in the study. Mean age 73 yrs (range 46 to 95), 54% female. The N-terminal BNP results were available in a minimum time of 24 hours; the Biosit& [email protected] BNP system results were available ln 20 minutes after testing. The mean N-terminal BNP result (Christchurch Cardioendocrine Research Group) was 103.0 pmol/l (95% CI 75.0, 131.O).The mean BNP-32 result using the BiositeB [email protected] BNP system was 56.2 pmol/l (95% CI 37.8, 74.6). Normal ranges: BNP-32, O-15 pmol/l, N-terminal BNP, O-50 pmol/l. The correlation between the assays was 0.948 (p 0.001). The results were also stratified as to whether they were clinically abnormal or within the normal range; this showed good agreement. The correct classification rate for the point-of-care assay was 90% (95% CI 82%, 96%) compared to the laboratory-based assay. Conclusions: Point-of-care BNP meters provide the possibility of immediate natriuretic peptide measurement. The meter tested performed with high agreement with a well-established laboratory-based assay.

THE INFLUENCE OF MEASURED VS ASSUMED OXYGEN UPTAKE fVO21 IN ASSESSING THE PULMONARY VASCULAR RESISTANCE (PVR) IN BIDIRECTIONAL GLENN (BDG) PATIENTS. CL. Shanahan*. N.1. Wilson, T.L. Gentles. I.R. Skinner. Cardiac Measurement, Green Lane Hospital, Auckland Purpose: To assess risk stratification for Fontan using PVRl calculated from measured V02 compared to PVRI from predicted V02, and other haemodynamic data. Method: 33 patients with a BDG underwent cardiac catheterisation prior to Fontan (wt:5.4-51.7Kg, age:O-12yrs). PVRI was calculated using directly measured V02 (Deltatrac metabolic monitor). Cases were stratified into high-risk, PVRI >4 (n= 6); moderate-risk, PVRl 3-4 (n=6); low-risk, PVRI <3 (n=21). This was also done using PVRl calculations from predicted V02 formulae by Lindahl, Lundell and LaFarge respectively Hemodynamic data, such as transpulmonary gradient (TPG) and pulmonary arterial pressure, were also investigated as alternatives. Results: Predicted V02 values were consistently higher than measured (mean differences -2O%, -57% & -23%), leading to an underestimation of PVRI with w difference from -0.62 to -1.57(U/m2), consequently misclassifying between 5 and 9 of the 12 moderate or high risk patients as low-risk. No other hemodynamic data could reliably separate low-risk from high-risk subjects. TPG >7mmHg was 100% specific for elevated PVlU, but only 33% sensitive (216pts). Conclusion: In assessing risk of Fontan failure in patients with BDG, V02 should be measured, not assumed, as all predictive V02 formulae lead to serious underestimation of true PVRl, and other measured data, including TPG, cannot be used as a reliable PVRl surrogate.

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WATER TRANSPORT IN FETAL LAMB MYOCYTES - ROLE OF AQUAPORINS D.S. Winlaw*. M Wintour. K Moritz P Manelick. D Cess. G Nun”. Adoph Basser Cardiac Institute and Department of Surgery, The Children’s Hospital at Westmead, Sydney, and Howard Florey Institute, Melbourne. Myocardial edema contributes to contractile dysfunction post-operatively and may occur as a result of ischaemia-reperfusion injury, the systemic inflammatory response to bypass, hemodilution and fluid overload. Water transport across cells occurs in response to osmotic/hydrostatic gradients: membrane permeability is enhanced by the insertion of aquaporin (AQP) molecules into the cell membrane. There are at least ten AQP isoforms (AQPs O-9), of which seven are pure water channels. AQPs 3,7,9 are also permeable to other small molecules eg. urea, glycerol. Aquaporin-1 has been identified in the myocardium of mice and rats. It is strongly expressed in the kidney and placenta as is AQPJ. In this study we used quantitative methodology (real time PCR)’ to determine the relative levels of AQP-I in left ventricle, kidney and placenta of the ovine fetus. A preliminary study was conducted to see if AQP-3 was also present in the heart. The levels of ventricle was 5.2&l .7 times three samples placenta.

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AQP-I in the late gestation (130 days, term=1 50 days) left I .6+0.5 (mean&em, n=7) times that of mid gestation kidney and that of mid gestation placenta. AQP-3 mRNA was detected in at 2-9 times that of the kidney but at only -20% of that in the

Preliminary investigations using immune-histochemistry and confocal microscopy in rat and human ventricular myocardium demonstrate that aquaporin-I is present at the periphery of cells and in the contractile apparatus near the Z-band. Substantial expression of these two AQPs in the mammalian heart suggests they may be potential targets for the future treatment of myocyte odema which occurs postoperatively. Studies are in progress to ascertain whether other AQPs are also exoressed in the heart.

TRANSCATHETER CLOSURE OF BIGGER ARTERIAL DUCTS WITH THE AMPLATZER DEVICE. P.G. Biarnstad’. G. Stake. Paediatric Clinic, and Radiology Department, Rikshospitalet, The National Hospital, Oslo, Norway The bigger open ducts have been a technical problem for the interventionist. From November -97 till January 2001 we have closed such ducts in 40 patients. The minimal diameter of the ducts measured with angiocardiography ranged from 2.1 to 7.0 mm. 17 (42%) measured from 3.0-3.9 mm, eight (20%) were 4 mm or more. The ratio between girls and boys was 1,85:1. The patients were between 0.3 and 81.9 years. 33 (82%) were treated during the first five years of life. They were between 4.0 and 77 kg and measured between 59 and 182 cm. Six of the patients had had earlier attempts of closure with the Rashkind umbrella or one or more coils. In one patient two Amplatzer plugs were used prior to the one that finally occluded the duct. Technical problems were encountered because the introducer sheath is vulnerable towards kinking. This applies particularly in the smaller patients with more acute curves in the right ventricular outflow and sometimes it was very difficult to advance the device through these curves. The duct was in most cases completely closed the following day A very, very small residual shunt, almost unrecognisable, was seen in two patients after 3 month’s and a year’s follow-up. Thus the complete closure rate was 95%. No other prblems was discovered during the procedures or the follow-up. Conclusion: The Amplatzer ductal occluder demonstrates optimal results in all bigger ducts in all age groups and sizes, and some procedural problems in the smallest patients. It seems to be the method of choice for all ducts bigger than 2.5 mm minimal diameter.

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ENHANCED VENTRICULAR FUNCTION FOLLOWING REPAIR OF COARCTATION OF THE AORTA IS A GEOMETRIC ARTEFACT RELATED TO CONCENTRIC HYPERTROPHY. T.L. Gentles* B.R. Cowan. C. Occleshaw. R. French, A.A. Young Departments of l’aediatric Cardiology and Cardiac Radiology Green Lane Hospital and the Departments of I’hysiology and Medicine Auckland University Background: Reports of enhanced LV contractility following repair of coarctation of the aorta (CoA) have used endocardial indices of LV shortening which overestimate myocardial fiber shortening in the presence of hypertrophy. Methods: Echocardiography (Echo) and magnetic resonance imaging (MRI) were undertaken in 15 patients aged 19 - 26 years 17 to 23 years after repair of CoA, and in 15 age, body size, and gender matched controls. Echo M-mode LV dimension (D) and posterior wall thickness (h) were measured at enddiastole (ED) and end-systole (ES), and fractional shortening (FS) was calculated. Regional deformation was calculated by MRl using a 3D tissue-tagging finite element model that allows tracking of portions of myocardial volume through the cardiac cycle and therefore direct measurement of myocardial shortening. Results: The Echo ED h/D ratio was elevated in CoA patients (0.18r0.02 vs. 0.15+0.02, p=O.O02) indicating concentric hypertrophy. Importantly, the Echo FS was also elevated (3724.5% vs. 33?4.6%, p=O.O2) while MRl circumferential midwall shortening (MRMWFS) was not (21+1.3% vs. 21*1.3%, p=NS). MRI longitudinal shortening was mildly reduced (14.9+1.3 vs. 16.8+1.4X p=O.OOl). Echo FS was related to MRMWFS and to ED h/D(r =0.68). Conclusions: These data demonstrate that circumferential shortening is normal, and longitudinal shortening mildly reduced after coarctation repair. Elevated endocardial shortening is a geometric a&fact, related to h/D and therefore exacerbated by concentric hypertrophy. Care should be taken when interpreting endocardial ventricular function indices in patients with concentric hypertrophy.

A COMPARISON OF SYSTOLIC BLOOD PRESSURE AND OTHER PARAMETERS BETWEEN AORTIC AND RADIAL BLOOD PRESSURE WAVEFORMS. SA Hone*. IT Meredith. ID Cameront Cardiovascular Research Centre, Monash University, Monash Medical Centre, and La Trobe Universityt, Melbourne. It is well known that the shape of blood pressure waveforms varies over the arterial system. Differences in pressure wave shape and associated descriptive parameters between brachio-radial and proximal aortic sites are of interest due to suggestions that central BP might be a more appropriate clinical indicator than traditional BP assessment. In 98 subjects (76M22F) undergoing elective coronary procedures, we simultaneously recorded invasive ascending aortic (6 or 7Fr coronary catheter) and radial artery (applanation tonometry, MillalB [email protected] catheter pressure transducer) pressure waveforms using Chart for Powerlab, sampling at 200Hz. Radial waveforms were subsequently scaled to aortic mean and diastolic BP by linear interpolation. Parameters for comparison included SBP, augmentation index (AI), diastolic (Ad) and systolic (As) pressure integrals and times to peak pressure (Tp) and to dichrotic notch (Ts). Results are expressed comparing radial with aortic sites. Scaled radial SBP was closely and linearly related to measured aortic SBP (v=O.9098x + 24.22; p
6.84resoectivelv: both L ,I p
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AGGRESSIVE CHOLESTEROL REDUCTION REDUCES LARGE ARTERY STIFFNESS IN ISOLATED SYSTOLIC HYPERTENSION (ISH). eK.E. F rrier M.H. M wt. I.D. Gamer .L. lenn’ A.M. Dart. B.A. Kimwell’. Alfred and Baker Medical Unit, Baker Medical Research Institute, Melbourne. To determine the effects of aggressive cholesterol reduction on large artery stiffness in patients with ISH. Twenty-three patients with stage I ISH (18/5, M/F; 6Oi3 years, mean&EM) underwent 3 months treatment with both atorvastatin (BOmg/day) and placebo in a randomised, cross-over design study. Measurements of carotid pressure via applanation tonometry and ascending aortic blood flow velocity via Doppler velocimetry, were made for calculation of systemic arterial compliance (SAC). Regional aortic stiffness was measured via pulse wave velocity (PWV; Doppler flow and ECG). Total and LDL cholesterol and triglycerides were reduced following atorvastatin, while HDL cholesterol trended to be higher (P=O.O6). Atorvastatin increased arterial compliance and distensibility and reduced systolic blood pressure (SBP). There was no change in either mean pressure (l’=O.61) or heart rate (P=O&). While atorvastatin did not affect PWV in the aorta between the arch and mid abdominal region (p=O.97) there was a trend for reduction in abdominal aortic to femoral PWV. LDL cholesterol (mmol.L-‘) Triglycerides (mmo1.L.‘) SAC (ml.mHg-‘) Distensibility (ml.mmHg-‘.cm-2) SBI’ (mmHg) Abdominal aortic PWV (m.s-‘)

Placebo 3.38 + 0.16 1.43 + 0.13 0.36 r 0.03 0.10 t 0.01 15423 13.1 * 1.1

Aggressive cholesterol reduction reduces large patients with stage I isolated systolic hypertension.

Atorvastatin 1.79 i 010 1.07 r 0.09 0.44 * 0.05 0.12 + 0.01 148+2 9.9 * 1.2 artery

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FIBRILLIN-1 GENOTYPE IS ASSOCIATED WITH AORTIC STIFFNESS AND CAROTID PULSE PRESSURE IN CORONARY ARTERY DISEASE PATIENTS. B.A. Kingwell*. T.L. Medlev, T.T. Cole. CD. Gatzka. I.D. Cameron, A.M. Dart. Alfred and Baker Medical Unit, Baker Medical Research Institute, Melbourne. To determine whether genotypic variations in the extracellular matrix protein firbrillin-1, the Marfan gene, were related to aortic stiffness and central pulse pressure in patients with coronary artery disease. One hundred and thirtyseven patients (108 male) aged 61+9 years (mean&D) with coronary disease confirmed by angiography were studied. Carotid applanation tonometry was used to assess central pressures and indices of central augmentation due to wave reflection, and in conjunction with Doppler velocimetry, to assess aortic input and characteristic impedance. Fibrillin-1 genotype was characterised by a pentanucleotide repeat polymorphism in intron 28. Three genotypes accounted for 85% of the population. Carotid blood pressures and impedance values were greater for the 2-3 genotype compared with the 2-2 and 2-4 genotypes. Peak exercise brachial systolic pressure was greater in the 2-3 compared to the 2-2 genotype (P=O.O3). 2-3 (n=1.5) 2-2 (n=79) 2-4 (n=Zl) P Frequency (%) 57.7 15.3 11 7 Z, (mmHg/s/cm-‘) 2.34*0.14’ 2.35+0.21’ 3.5OkO.46 0.005 1.54r0.08’ 1.54+0.15” 2.27+0.31 0.006 Z, (mmHg/s/cm~‘) Carotid SBP (mmHg) 125+3’ 132+6’ 145*6 0.009 50.3C2.4’ 59.3zt4.8’ 662~7.3 0.004 Carotid l’l’ (mmHg) 11.0+1.1* 15.0+2.5 19.2+3.1 0.015 AP (mmHg) Z, input impedance; Z,, characteristic impedance; SBP, systolic blood pressure; PP, pulse pressure; AI’, augmentation pressure * significantly different from 2-3 (l’cO.05). There was no difference in age, gender, terol level, mean pressure or medication data suggest that fibrillin-1 genotype is artery stiffness and central pulse pressure disease.

body mass, smoking status, cholesbetween the three genotypes. These an important determinant of large in individuals with coronary artery

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INHIBITION OF CALCINEURIN DOES NOT PREVENT HYPERTROPHY IN A RAT PRESSURE-OVERLOAD MODEL. AC McMahon.* SHL Fene ev. Department of Cardiology, St Vincent’s Hospital, Sydney NSW. Although the calcineurin / NF-AT3 pathway has been shown to be important in the development of skeletal muscle hypertrophy, its role in the development of cardiac hypertrophy remains controversial. The aim of this study was to investigate the effect of calcineurin inhibition on the induction of left ventricular hypertrophy (LVH) in response to a pressure load. Male Wistar rats were randomly assigned to one of two groups: Group 1 received 1 mg/kg FK506 daily by IP injection (FK) and Group 2 received an equivalent volume of saline daily, also by IP injection (S). After 3 days, half of each group was then subjected to banding of the transverse aortic arch between the inominate artery and the left carotid artery (8). The band was sufficiently tight to induce a peak pressure gradient of -35 mmHg. The remaining animals were subjected to a sham-operation (C). Daily injections were continued throughout the study. After 21d, blood pressures were measured directly from the left and right carotid arteries under terminal anaesthesia; hearts were then removed, trimmed and left ventricular (LV) weights measured by a single blinded operator. LVH is expressed as an increase in LV / body weight ratio. Results are mean&E. There was no difference in the pressure gradient induced between SB and FKB (35+5, n=lO vs 33+5 mmHg, n=9 respectively). Banding induced a significant increase in LV / body weight ratio of 12+3% (p
LONG TERM CARDIAC-PROTECTIVE EFFECT OF ANGIOTENSIN II ANTAGONISTS IN ESSENTIAL HYPERTENSION: LOSARTAN VERSUS LOSARTAN PLUS HYDROCHLOROTHIAZIDE. TWC Yip’*, P Chookz, LLT ChanZ 02. WH Funez.~. PY Ho2. TC Law’, E Sanderso&. KS Woo2 Yan Chai Hospital’ and The Chinese University of Hong KongZ, Hong Kong SAR. Background: Angiotensin II antagonist (AIlA) is an emerging antihypertensive drug with appealing pharmacokimetic and safety profiles, but evidence for event endpoints reduction is awaiting. Increased left ventricular mass (LVM) is an important prognostic marker for these events. Methods: To evaluate the long term impact of AIL4 on LVM, 26 patients (mean age 52.1k8.6 years, 11 males) with essential hypertension (DBlQ90mmHg after 4 weeks placebo washout) were studied. They were given open-labelled Losartan (50mg titrating to lOOmg/day if DBlQ90mmHg) or Losartan + Hydrochlorothiazide (50mg+12,5mg/day) (Hyzaar) for 12 months in randomized parallel design. 2D-guided M-mode echocardiography was performed at baseline and again at 6 months and 12 months after treatment. LVM was measured offline by the same blinded investigator. Results: Similar significant blood pressures reduction was achieved and maintained at 6 and 12 months, with no significant changes in their heart rate, renal function, blood potassium and urate levels. Significant and progressive reduction in LVM was evident in both groups at 6 months (mean 7.Ok6.7, 95% CI 3.1 to 10.9g/m2 with Losartan; mean 13.9*11.4, 95% CI 6.6 to 21.1g/m2 with Hyzaar, p>O.3) and at 12 months (mean 11.8+_7.5, 95% CI 7.4 to 16.1g/m2 with Losartan; mean 18.9i15.7, 95% CI 8.9 to 28.8g/m2 with Hyzaar, p>O.3) respectively. The mean annual drug costs were US$401.6+144.5 and $281.1 respectively for each patient (p
12 Mth >

Hyzaar (n=lZ) < Baseline

12 Mth >

156.5&11.6 132.5+11.1 147.8t12.4 130.0+9.5 93.7e5.4 80.0+5.3 92.426.3 81.1+4.3 DBP (mmHg) LVM Index (g/M2) 112.1GJ6.8 100.3?22.5* 110.7~31.0 91.8?22.4* 4.7*0.4 4.5kO.4 4.4kO.5 4.4kO.3 LVDD (cm) 1.23r0.28 1.09+0.13 Ivs (cm) 1.16+0.22 1.13+0.19 1.03?0.24 0.95+0.11 LVPW (cm) 1.03*0.15 0.98+0.12 70.4+7.7 71.6k9.8 68.1+11.4 EF (%) 71.7t6.3 ( * comparing with baseline and 12 weeks, p
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THE CONTRIBUTION OF VASCULAR ATP-SENSITIVE POTASSIUM (KATP) CHANNELS AND VASODILATOR PROSTANOIDS TO RESTING AND EXERCISE-INDUCED SKELETAL MUSCLE BLOOD FLOW. HMO Farouaue*. SG Worthley. MA Baldi. Ml Zhane. RC O’Brien & IT Meredith. Cardiovascular Research Centre, Monash University and Monash Medical Centre, Melbourne. Experimental data suggest that vascular KATP channels are determinants of metabolic vasodilation. We have shown that glibenclamide (GLIB) infused into the brachial artery at 15&/min attenuates diazoxide-induced vasodilation by 15% in forearm vasculature, indicative of vascular KATP channel inhbition. However, functional hyperaemic blood flow (FHBF, induced by 2 minutes of isotonic forearm exercise) was not altered. Therefore, we assessed the effect of high dose GLIB infusion (lOOpg/min) on FHBF in 5 healthy subjects (age 24+8 years; 2M, 3F), using the technique of venous occlusion plethysmography. Compared to vehicle infusion (0.9% saline), high dose GLIB did not alter peak FHBF (13.5r1.3 vs 13.0i1.2 ml~lOOm1 forearnl.min-1; P=O.34), forearm vascular resistance (FVR, 6.9kO.7 vs 7.5t0.6 arbitrary units; P=O.O9) or blood volume repaid to the forearm after 1 and 5 minutes. Mean arterial blood pressure (MABP, 92+2 vs 95+1 mmHg; P=O.O4) and plasma insulin (9.1k1.3 vs 22.9k2.9 mU/L; P=O.O02) rose after GLIB, although heart rate and plasma glucose were unchanged. The relative contribution of vasodilator prostanoids and vascular KATP channels to basal forearm blood flow (FBF) and FHBF was examined by co-infusion of aspirin (3mg/minute) and GLIB (15&g /min) in 19 additional healthy subjects age 25t6 years; llM, SF). Aspirin alone reduced FBF by 22% (2.3t0.2 to 1.8eO.2 ml~100ml forearm-l.min-1; P=O.O04). Compared to vehicle, co-infusion of aspirin and GLIB decreased FBF by 20% (2.1+0.2 to 1.7+0.2 ml.lOOml forearm-l.min-1; P=O.OOl). Aspirin reduced peak FHBF by 15% (14.2t1.4 to 12.1&l ml~lOOm1 forearm-l.min-1; P=O.O02) and increased minimum FVR by 15% (P=O.O03). Blood volume repaid after 5 minutes was reduced by 14% (l’=O.O3). Compared to vehicle, co-infusion of aspirin and GLIB decreased peak FHBF (P=O.O07), reduced blood volume repaid after 5 minutes (l’=O.Ol) and increased minimum FVR (P=O.OOl), but not to a level greater than aspirin alone. There was no alteration to FBF in the contralateral arm, heart rate, MABP or plasma glucose, although plasma insulin increased after GLIB (6.1+0.6 to 9.4t0.9 mLJ/L; P
UROCORTIN PROTECTS ADULT RAT CARDIAC MYOCYTES FROM SIMULATED ISCHAEMIA IN VITRO. JM Gordon’. GT DustinP & H Ritchie. Howard Florey Institute, University of Melbourne, Vie, 3010 Cardiac myocytes (CM) can be protected from a potentially lethal ischaemic insult by preconditioning with transient ischaemia. Release of adenosine by the heart is a known trigger of preconditioning. Urocortin, a novel member of the corticotrophin releasing hormone family, has recently been shown to protect neonatal rat cardiac myocytes from simulated ischaemia-reperfusion injuryl, but its cardioprotective potential in mature (adult) rat cardiac myocytes has not yet been determined. We have recently described a model of simulated ischaemia/reperfusion injury in isolated adult rat cardiac myocytes which exhibits both pharmacological (adenosine) and both ischaemic (classical and late-phase) preconditioning2. Using this model, we tested the hypothesis that urocortin protects isolated adult rat cardiac myocytes against cellular injury. Myocytes were incubated in a simulated ischaemia buffer (HEPES buffer supplemented with 10 mM 2-deoxy-Dglucose and 20 mM D,L-lactic acid, pH 6.5) for 4h at 37°C. Paired control cardiac myocytes were incubated in normal HEPES buffer (pH 7.4). Cardiac myocytes were then allowed to recover in defined serum-free medium for 2.5h. The protective effects of adenosine (10~M) or urocortin (0.1~M) during simulated-ischaemia were assessed as the reduction in lactate dehydrogenase (LDH) and creatine kinase (CK) activitv as a oercent of that induced bv simuiated ‘ischaemia alone (mean f SE<. SimLlated ischaemia signiecantly increased LDH activity by 463+111 IU/lO5 cells (n=19, P
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BRADYKININ BLOCKS THE ACUTE HYPERTROPHIC RESPONSE TO ANGIOTENSIN II IN ISOLATED PERFUSED RAT HEARTS. A.C. Rosenkranz. S.G. Hood. R.L. Woods, G.I. Dustine and R.H. Ritchie*, Howard Florey Institute, University of Melbourne, VIC 3010, Australia The antihypertrophic effect of ACE inhibitors in viva depends in part on bradykmin (BK). BK prevents angiotensin II (Ang IQ-induced cardiomyocyte (CM) hypertrophy in vitro by releasing NO from endothelial cells to elevate cyclic GMP in CM.1,2 Furthermore, we recently demonstrated that elevation elevation of cyclic GMP with &bromo-cGMP or natriuretic peptides, also blocks CM hypertrophy induced by Ang II. The aim of the present study was to directly demonstrate an antihypertrophic effect of BK in whole hearts, and to determine the role of cyclic GMP in this response. The antihypertrophic action of BK was compared to that of an NO donor (sodium nitroprusside, SNP) in isolated Langendorff-perfused rat hearts. Following equilibration, hearts were perfused for 90 min with Krebs perfusion buffer alone or supplemented with BK (100 nM) or SNP (3 PM). Ang II (10 nM) was added to the perfusion buffer after the first 30 min. Hearts were then perfused in drug-free buffer containing [3H]phenylalanine (0.25 pCi/mL) for 60 min. The left ventricle (LV) was snap-frozen at the end of perfusion. [3H]Phenylalanine incorporation was determined in LV homogenates as an in vitro marker for hypertrophy, and cyclic GMP levels were measured by radioimmunoassay. Perfusion with Ang II significantly increased [3H]phenylalanine incorporation by 93?27% of that observed with drug-free controls (n=13, P
LONG HAUL PULMONARY EMBOLISM S. Hertzbere, G. Mathur.G. Crannev, W. Walsh. Sydney, NSW

TO SYDNEY. Prince of Wales

S. Roy”. Hospital,

Introduction: Several small European and North American series have addressed the phenomenon of thromboembolic events associated with long haul air travel with conflicting results. Sydney airport is a major international gateway, with more than 50% of incoming flights being nine hours or more in duration. By virtue of it’s proximity to the airport, Prince of Wales Hospital receives the majority of patients who have become unwell during or immediately after their flight. The aim of this study was to report our institution’s experience of pulmonary embolism (PE) associated with long haul air travel. Method: A retrospective analysis of the records of all patients presenting to the Emergency Department with confirmed PE over a three year period was undertaken. Those patients admitted directly from the airport were specifically reviewed. Results: Ten patients, mean age 65.5 yrs (range 50-76), four male and six female, were admitted directly from the International Airport to the Emergency department with PE. All of these patients had flown for at least nine hours, and only three had identifiable risk factors for thromboembolic disease. Five of the six patients with features of haemodynamic instability and/or right ventricular dilatation on cardiac echo were successfully thrombolysed. The sixth patient, who had required resuscitation after a cardiac arrest in transit to the Emergency department, was found to have a patent foramen ovale and paradoxical cerebral embolus. He was ineligible for thrombolysis, and died the following day. The four remaining patients had an uncomplicated hospital course with conventional anticoagulant therapy. During the period of our review, 6.58 million passengers arrived in Sydney on long haul international flights. Conclusion: The incidence of PE associated with long haul air travel is very low. However our experience suggests that this may be an independent risk factor for potentially life threatening pulmonary embolism.

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DEPRESSIVE SYMPTOMS, HEALTH STATUS AND MORTALITY IN THE LIPID STUDY. R,Stewart.* S. Mulrav. 1. Simes. D. Colauhoun. H. White and A. Tonkm for the LIPID studv investieators. Green Lane Hospital, Auckland, New Zealand Recent studies suggest patients with depression and cardiovascular disease have a higher mortality, but the explanation for any association is uncertain. This study describes associations between depressive symptoms, measures of health status, and mortality in the ‘psychological sub-study’ of the Long term Intervention with Pravastatin in Ischaemic Disease (LIPID) study Method: Symptoms of anxiety and depression were assessed at the randomisation visit in a selected sample of 1130 LIPID study participants using the ‘General Health Questionnaire’ (GHQJO). Associations with general health, symptoms of cardiovascular disease and coronary risk factors at the same visit, and cardiovascular (n= 185) and total mortality (n=253) during 9027 patient years follow-up were assessed. Results: Depressive symptoms (GHQ score 25) were more common in younger subjects (age ~50, 36% of subjects, age 50-60, 25%, age>60, 21%, p
LONG-TERM RISKS ASSOCIATED WITH ATRIAL FIBRILLATION THE RENFREW/PAISLEY STUDY. S. Stewart*, C.L. Hart, D.J. Hole and J.J. McMurray CRI in Heart Failure and Department of Public Health, University of Glasgow, Glasgow, Scotland. Background: The aim of this study was to examine the impact of atria1 fibrillation (AF) on cardiovascular-related hospitalisation and mortality and on allcause mortality in 15,406 middle-aged men and women followed for 20 years. A particular focus was the association between AF and the risk of developing heart failure in the light of growing interest in the concept of tachycardiamediated cardiomyopathy. Methods: The Renfrew/Paisley Study originally surveyed persons aged 45-64 years living in these two towns in the West of Scotland. Approximately 80% of the target population (7,052 men and 8,354 women) was examined between 1972-1976. All subsequent hospitalisations and deaths (and their attributable cause) 20 years thereafter were documented. Results: At baseline, 100 subjects (0.65%) had AF; overall they were older and more likely to have preexisting cardiovascular disease. During follow-up, 89% of women with baseline AF experienced a major cardiovascular event (death or hospitalisation) compared to 32% of those without AF (P < 0.001). The equivalent figures for men were 66% versus 45% (P < 0.01). After 20 years, 72% of men and 78% of women with AF at baseline screening had died, compared to 44% and 28% of those without AF (P < 0.001). In both men and women, AF was a significant (P < 0.05 for all comparisons), independent risk factor for all-cause death (adjusted risk ratio 1.49 and 2.23, respectively), a major cardiovascular event (1.77 and 2.99), a fatal or non-fatal stroke (2.48 and 3.41) and a major heart failure event (2.24 and 3.40). As such, AF was the strongest independent predictor of subsequent heart failure events in women. Conclusions: As reported previously, AF is an important predictor of stroke. However, AF is an even more powerful predictor of heart failure events and an independent predictor of both cardiovascular and all-cause death, particularly in women. AF, detected in middle-aged men and women, is an important cause of both heart failure and stroke. Therapeutic strategies aimed at preventing heart failure, as well as stroke, are needed in those patients with AF.

Heart,

Lung

and Circulation

2001; 10

DETERMINANTS OF PROGRESSION OF CAROTID INTIMA-MEDIA WALL THICKNESS IN A COMMUNITY-BASED POPULATION. QPLTh ill S Nidorf rittenden. WA Heart Research Institute (Sir Charles Gairdner Hospital campus) Nedlands WA. Carotid intima-media wall thickness (IMT) as measured by high-resolution B-mode ultrasound is strongly correlated with established risk factors and increased IMT is generally thought to be an indicator of early atherosclerosis. However, it is uncertain if serial monitoring of carotid IMT will be a useful or reliable method to determine atherosclerosis progression in a communitybased population. The aims of this study were to assess the rate and determinants of progression of carotid mean IMT in a community-based population. Methods. In a randomly selected adult population carotid intima-medial thickness was measured on 1111 subjects, of whom 859 were m-examined at 18 months and 777 at 36 months (706 measured at every time point). Results. There was a mean progression of IMT overall, though in this generally healthy population the rate of progression was low (mean O.Olmm per year). Mean IMT mm + SD Mean change in IMT mm Proportionate increase %

Baseline 0.642 + 0.121

18 months 0.657 f 0.126 0.013 * 0.063 2.02

36months 0.673 k 0.121 0.031 + 0.063 4.8

Factors significantly associated with IMT progression (n=777) on univariate analysis included age and sex, blood pressure, body mass index, lipids (not HDL), ferritin, and vitamin E. Pack-years of smoking was not significantly associated with progression. The baseline IMT was negatively associated with progression. Among females, age, blood pressure, lipids and ferritin were associated with progression, while for males baseline IMT, HDL, homocysteine (negative) and vitamin C were significant. The rate of progression was significantly greater for those above the lowest tertile of composite Framingham risk score (inclusive of age). Tl 0.018 *O.O4mm, TZ 0.039 + 0.06mm p=
IN AN URBAN ABORIGINAL POPULATION, PRESCREENING FOR CARDIOVASCULAR RISK FACTORS IMPROVES UP TO NINEFOLD THE YIELD OF POSITIVE EXERCISE TEST RESULTS. T Leahv*. PI BradThompson. shaw P L Heart Research Institute of Western Australia and the Derbarl Yerrigan Health Service Perth. The indigenous population of Australia has among the highest rates of premature death of death from ischaemic heart disease of any group in the world. Detection of those at highest risk who may benefit from medical therapy or revascularisation is an urgent priority In this study, exercise testing to detect myocardial ischaemia was evaluated. In a community study of 998 members of the Aboriginal community of Perth, a detailed cardiovascular health evaluation was conducted. This included a lifestyle and cardiac health questionnaire, blood pressure and serum lipid estimation. From this evaluation, the risk of IHD was calculated using a Framingham risk equation. 483 subjects consented to an exercise test which were conducted on 463. The Bruce treadmill protocol was used. 23 subjects (5%) had a positive test defined as the development of >lmm of ST segment depression in contiguous leads. In determining the relationship between risk score and positive EST those who had a history of angina or myocardial infarction (9) were excluded from the analysis. When the remaining subjects were categorised by their Framingham risk score, the proportion of positive tests in those in the lower two quartiles was very low (1%). In contrast, the proportion of positive tests in the upper two quartiles was high (5.4% and 9.2% respectively) (see figure). In this population of urban Aboriginal people, the yield of tests suspicious of myocardial ischaemia can be increased up to 9 fold by prescreen9.2 10 ru ing with standard cardiovascular 2 81 5.4 risk factors. “E 6 Conclusion If exercise testing is to -z41 50 be considered for detection of g 12 2 I 0.9 .Eg ,,~--o_ dl _~ ischaemic heart disease in Aboriginal OD. populations, it should be targeted to 2 3 4 e I c those at intermediate or high risk on Quartile of Framlngham. score preliminary risk factor evaluation.

Heart,

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2001;

49th Annual

10

THE REALITY OF INFORMED CONSENT IN A MULTICENTRE THROMBOLYTIC TRIAL: A HERO-Z SUBSTUDY. B.F. Williams’lL J K Frenchl. D. Schmidl, F.D. Sawtelll, W.I. Youneu. M. D~ole~~~ &I. whit&. for the HERO-Z Consent Studv Investieators, Cardiovascular Research Unit, Green Lane Hospitall, North Shore Hospita12, Auckland, and Hawkes Bay Hospita13, Hastings, New Zealand. The ability of a patient to give written informed consent requires comprehension of both written and verbal information. At presentation with acute myocardial infarction (AMI) this ability may be impaired by several factors including fear, pain, morphine administration and educational status. To evaluate the consent process we studied 328 patients in New Zealand and Australia who were invited to participate in the HERO-2 trial including 24 (7.3%) who declined participation. Gender and mean age of patients consenting and declining were similar (73% male, 63 years). Prior to discharge we analysed readability of information sheets with respect to educational status, and patient-assessed comprehension of information using a verbal questionnaire. Only 18% of patients read the information sheet before consenting or declining. Consenting patients received more morphine (6 r 6mg) than decliners (4 ? 4 mg, p= 0.04) but this did not impair memory of the consent process (93% vs 91%, p= NS). For adequate comprehension of the written information a > year 12 (form 6) education was needed; only 22% had been educated beyond secondary school. More patients who consented, compared to those who declined, reported good or partial comprehension of verbal information (94% vs 71% p ~0.01) and initial overall comprehension of information (90% vs 71% ~~0.05). Prior to discharge, compared to at consent, the level of comprehension of all patients had improved (good 45% vs 19% partial 52% vs 69010, poor 3% vs 12%; p
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ROUTINE

TRANSTHORACIC ECHOCARDIOGRAPHY DOES NOT AFFECT INPATIENT MANAGEMENT OF STROKE. K. Murchie? D. Prior, D. Haikerwal. Cardiovascular Medicine. Alfred Hospital, Melbourne Australia. Background: Approximately 20% of cercbrovascular events are attributed to a cardiac source of embolus. Current evidence suggests that transthoracic echocardiography (TTE) has a low yield for diagnosing cardiac source of embolus. Often, this is in the setting of atria1 fibrillation (AF), left ventricular (LV) dysfunction or patent foramen ovale (PFO). Management is rarely changed by TTE results. Anticoagulation for AF is empirically commenced. Despite this TTE is still frequently requested following a TIA/CVA. We retrospectively examined the Alfred Hospital Methods: echocardiography database over a one-year period. A total of 3433 TTE were performed; IO5 (3%) of these requests were post TIA/CVA seeking cardiac source of embolus. m The mean age of the patients was 65 years (69 male, 36 female). The majority were in sinus rhythm (80%), 13% were in atrial fibrillation. LV function was normal in 80% of subjects, 9% had moderate or severe LV dysfunction. No detinite thrombus was detected in any patient, 2 subjects had a PFO confirmed with contrast, and there were no patients with spontaneous echo contrast (SEC). In 3328 TTEs performed for other indications, LV thrombus was detected in only 6 patients and atrial thrombus in one patient with concomitant severe mitral stenosis Only due first one from

five patients proceeded to transoesophageal echocardiography (TOE) to sub-optimal TTE imaging. A further I3 patients had a TOE as their procedure. TOE detected SEC in one patient, PFO in two patients, and patient with severe LV dysfunction. No changes in management resulted either TTE or TOE findings.

Conclusions: TTE is a low yield investigation for cardiac source of embolus. In patients whose management may be altered by a test, we suggest that TOE may be the primary investigation of choice.

COMPARISON OF CARDIAC REXIABILITATION (CR) AND COACHING ON RISK FACTORS IN PATIENTS WITH CORONARY HEART DISEASE (CHD). M.V. J&l&*. M.J. Vale. D.L.Hare. J.D. Bti On behalf of the COACH study group, Melbourne, Victoria.

MORPHOLOGY OF THE RHEUMATIC MITRAL REGURGITANT VALVE BY THREE-DIMENSIONAL ECHOCARDIOGRAPHY. S.P.Wone*. R.A. French. E.L Bolson. M.E. LePoet. EH. Sheehan Green Lane Hospital, Auckland, New Zealand and University of Washington, Seattle, WA, USA.

Background: The practice of CR is supported by one randomised controlled trial (RCT) and one quasi-experiment. A number of RCT’s have been performed in Australia hoping to show that phase 2 CR programs improve quality of life by reducing anxiety and depression. None has been successful. It is reasonable to suppose that if CR programs prolonged life they might do so by improving the cardiac risk status of patients who had undergone CR. The

Background: Rheumatic fever remains a significant worldwide cause of mitral regurgitation (MR). Detailed quantitative morphology of the valve apparatus in this disease is not well described but would aid surgical repair. In this study the increased quantitative information from three-dimensional (3D) echocardiography was used to describe the valve. Methods: Eight normal subjects and 16 patients (mean age 29%12 years) with mild (N=7) or moderate to severe (N=9) rheumatic MR underwent 3D echo using freehand transthoracic scanning. LV borders, mitral chordae, papillary muscles and annulus were traced at end-diastole (ED) and end-systole (ES). LV surfaces and the mitral annulus were reconstructed in 3D. Regional LV function was assessed using myocardial thickening. Alignment of ED endocardial surfaces to a reference normal surface was used to assess regional LV shape. Results: Compared to normals, the patients with MR had more spherical LVs (sphericity index 0.47 v 0.36, p=O.Ol). The septum was less expanded than the opposite LV walls, in which the expansion from the reference normal LV shape measured 9+8mm. LV volumes and ejection fraction did not differ from normals and function in the regions of papillary muscle attachment was not reduced. The mitral annulus was increased in 3D length and area (ED 11.5 v 8.1cm2, p=O.O3; ES 11.0 v 8.0cm2, p=O.O3). These annulus parameters correlated with LVED volume (ED area R=0.66, p
COACH

stidy

allows

us to examine this hypothesis.

Methods: A retrospective analysis was performed on the patients in a RCT of coaching, contrasting the risk factor status of patients with CHD who had undergone CR compared with those who had not. Results: At least one session of CR was attended by I76 (53%) of 33 1 patients who were coached and by 199 (57%) of 348 patients who underwent usual care. The fall in lipid levels (nunoK) from baseline to 6 months in attenders and non-attenders is shown in the Table. 1 ATC 1 ATG 1 AHDL-C 1 ALDL-C i (95%CI) (95%CI) (95%CI) (9S%Cl) i Rehab 0.51 0.19 -0.11 0.53 (0.38 to 0.63) (0.07 to 0.31) (-0.07 to -0.14) (0.32 to 0.65) No Rehab 0.31 0.17 -0.10 0.34 (0.17 fo 0.54) (0.04 to 0.30) (-0.06 to -0.13) (0.21 10 0.46) , / Difference: 0.20 0.02 -0.01 0.20 ) Rehabvs (0.01 to 0.38) (-0.15 to 0.20) (-0.05 lo 0.03) (0.03 to 0.37) NoRebab 1 I I P I 0.03 I NS NS 1 0.02 I Multivariate analvsis showed that the imoact of CR was confined to Datients in the usual care group. CR had no significant impact on arterial blood pressures (BP) or the proportion of current smokers ar 6 months or the Aweight from baseline to 6 months. By contrast, coaching lowered ATC more than did usual care by 0.44 (0.26-0.63) mm&L and the ALDL-C by 0.42 (0.25 _ 0.58) mmovL. In addition coaching resulted in significantly lower BP and weight. Conclusion: Coaching is far more effective than CR in its impact on treatable risk factors in patients with CHD.

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Heart, Lung and Circulation 2001; 10

THREE-DIMENSIONAL MEASUREMENT OF THE MITRAL LEAFLETS FROM ROTATIONALLY SCANNED IMAGESIN VITRO VALIDATION. G Ba er. University of Washington, Seattle, WA, Greenlane & Auckland Hospitals, Auckland, New Zealand and ATL Ultrasound Bothell ,WA ,USA

A NOMOGRAM FOR THE AUSTRALIAN POPULATION DEVELOPED FROM CORONARY ARTERY CALCIUM SCORES USING HELICAL GATED CT. RGT Walker*, SM.Nidorf, PL Thompson, S.Nair and D.Grout. Sydney Heart Image, NSW and West Australian Heart Research Institute, WA, Australia.

Objective: Three-dimensional echocardiography offers promise for improved understanding of mitral leaflet pathology, but it has not been validated quantitatively. This study assessed its accuracy with hearts in vitro. Methods: Pig hearts were pressurized with liquid silicone rubber to fix the mitral leaflets in closure. The left atrium was unroofed, four fiducial marks were placed in each annulus, and the hearts scanned in saline using a specially programmed ATL HDI 5000 ultrasound system and an MPT7-4 5. 5 MHz multiplane TOE probe. A networked computer drove transducer rotation in 5 deg increments and recorded the polar ultrasonic data. The leaflets and fiducial marks were traced manually, and the data put into a common 3-dimensional coordinate system. Dental impression material was used to make casts of the atria1 surface of the leaflets, which were digitized with a laser scanner. The laser and ultra-sonic fiducial marks were aligned by a least squares algorithm, and the distances between the laser and ultrasonic leaflet data were measured in the direction parallel to the rotational axis of the transducer. Results: Preliminary analysis of data from 7 hearts1) Average root mean square fiducial registration error: 0.96 mm. 2) Overall mean absolute deviation between ultrasound and laser data: 1.00 mm (average of 1510 points per heart). 3) Average of the median absolute deviations: 0.58 mm; average of the interquartile ranges: 0.82 mm; and average of the 90th percentile deviations: 2.01 mm. The large errors (>3 mm) tended to occur near the annuli, which were poorly defined in this motionless model, and in regions where the ultrasound beam intersected the anterior leaflet acutely. Conclusions: Three-dimensional rotational scanning enables accurate modeling of most of the surface of mitral leaflets in vitro. With improved definition of the annulus due to motion in viva, transesophageal three-dimensional imaging may become a major tool for studying mitral leaflet pathology and repair.

Background: Recent studies have shown that age/sex adjusted coronary artery calcium (CAC) score percentiles may be an effective way to stratify individuals at risk of coronary artery disease (CAD). A nomogram for CAC using EBCT has been done in the US population. There have been no nomograms developed for the Australian population. Methods: A nomogram of CAC score percentiles indexed for age and sex was developed from data obtained in 6411 asymptomatic men and 3049 asymptomatic women aged between 25-85 years who underwent CAC screening using helical gated CT (Toshiba, Aquilion). 35.5% of the men were smokers, 16.8% had hypertension and 11.2% were diabetic. Of the women, 29.7% were smokers, 23.3% had hypertension and 6.4% were diabetic.

VARIATION OF M-MODE BUT NOT TWO-DIMENSIONAL ECHOCARDIOGRAPHIC ESTIMATES OF LEFT VENTRICULAR MASS IN PATIENTS BEFORE AND AFTER HAEMODIALYSIS. PM, RI Graham. RE Peverill. L Donelan. IS Gelman. IJ Smolich’ Centre for Heart and Chest Research, Department of Medicine, Monash University, and Cardiology Unit, Monash Medical Centre, Clayton, Victoria. Background, Aim and Methods: Increased left ventricular mass (LVM) is an independent predictor of cardiac risk and is most readily assessed with echocardiography. In chronic renal failure (CRF) patients, LVM calculated from M-mode echo images is known to be confounded by load-related changes in cardiac dimensions which accompany haemodialysis. However, it is unclear to what extent such variation in calculated LVM occurs wifh 2-dimensional(2-D) echo formulae incorporating both LV short and long axis dimensions. To address this question, standard M-mode and 2-D echo images were obtained in 14 CRF patients immediately before and after routine haemodialysis. M-mode LVM was calculated according to the American Society of Echocardiography convention using a cube formula incorporating septal thickness (ST), posterior wall thickness (PWT) and left ventricular internal diameter (LVID). With 2-D echo, LVM was obtained with area-length or truncated ellipsoid formulae incorporating measurements of LV endocardial and epicardial cross-sectional areas at the midpapillary muscle level, and the LV apex to papillary muscle and papillary muscle to mitral annulus lengths. Results: Dialysis decreased body weight from 69.3k16.6 to 67.6+16.2(SD) kg (p
Men-Asymptomatic I 8 1sal i>;zsz&

Women-Asymptomatic 1:;

10.14 li-19CM 454 IO.54 ICIPdodl65hV‘I il

10II 1’1 1od4IS4 5x4 II.% hw 6% 7&Y

Agr

Age

Conclusion: This is the first large Australian data of its kind reference for men and women in the Australian population

and provides

REGIONAL RIGHT VENTRICULAR SENNING REPAIR. edemann.‘ F. W i Me L. r ns ’ 1 Cardiology and Paediatric Cardiology,

FOLLOWING

STRAIN

IMAGING

UZ Gasthuisberg,

Leuven,

a

rland. Belgium.

Background: Non-invasive assessment of right ventricular (RV) function following Senning repair would benefit from the characterization of regional myocardial deformation. Ultrasound strain imaging quantifies local deform ation independent of overall heart motion and contraction of adjacent segments. Methods: Colour Doppler myocardial imaging regional RV data were obtained at high frame rate (150 frames/s) in 16 children who were 14t4 years post Senning repair. Data post-processing was performed to determine longitudinal end-systolic strain values for the basal, mid and apical segments of the RV free wall. Regional RV deformation parameters were compared with the global RV ejection fraction (EF) assessed by magnetic resonance imaging (MRl). Results: End-systolic RV free wall longitudinal strain values were homogeneous for all three segments measured (base: 15*5%; mid: 15*7%; apex: 16+6%) over the range of MRI EF (30-65%). No patient had regional wall motion abnormalities on 2-D imaging. Regional longitudinal end-systolic strain of the basal RV free wall segment and the global ejection fraction were strongly correlated (r=0.91). Conclusions: In children with normal or globally reduced function following Senning repair, regional longitudinal end-systolic strain valCorrelation: r=o.91; p4.0001 ues correlate well with RV global function indices assessed by MRI. This new quantitative ultrasound approach could be of value in the bedside assessment of systemic RV function following Senning repair.

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SERIAL IMAGING WITH IN VIVO MAGNETIC RESONANCE OF ATHEROSCLEROSIS IN WHHL RABBITS: EFFECTS OF ATORVAS:SG W rthle * TATIN AND AVASIMIBE. ZA Favad. IT Meredith, V Fuster, TT Badimon. Cardiovascular Research Centre, Monash University, Monash Medical Centre, Melbourne and the Cardiovascular Institute, Mount Sinai School of Medicine, New York. The ability to monitor serially and noninvasively atherosclerotic (AT) plaques could provide insight into mechanisms of plaque stabilisation. Magnetic resonance imaging (MRI) can potentially be used for this purpose. We studied the effects of lipid lowering (atorvastatin), alone and in combination with an acyl-coenzyme A:cholesterol O- acyltransferase (ACAT) inhibitor (avasimibe) in Watanabe Heritable Hyperlipidaemic (WHHL) rabbits. AT lesions were monitored using MRI and histopathology. Induction of aortic AT was accelerated with balloon denudation in WHHL rabbits, after baseline MRI. Evolution of AT lesions was monitored by MRI using fast spin echo. After AT induction all animals were again imaged, with one group (atherosclerotic control) sacrificed and processed for histopathology. The remaining animals were randomized into AT progression control (no therapy, n=3), AT regression with atorvastatin 5mg/kg/day alone (n=3) and AT regression with atorvastatin 5mg/kg/day and avasimibe 25mg/kg/day (n=3). The third MRI was performed 6 months after randomisation. The effects of the different treatments on AT lesion progression were assessed by MRl and histopathology using vessel wall area (VWA), a surrogate of atherosclerotic burden, and presented as mean&EM (units mm2). There was a progressive increase in VWA after AT induction (baseline 3.61tO.01, induction 5.57kO.01). Control rabbits had a continued progression of AT after randomisation (VWA 7.16+0.03) Rabbits treated with atorvastatin alone experienced an attenuated increase (VWA 6.71*0.03), although this was not significantly different from controls (p=O.O8). The combination of atorvastatin and avasimibe induced a significant regression of the previously established AT lesions (VWA 4.54t0.04). There was an excellent agreement between MRI and histopathology assessment of VWA (p
A NOVEL NON-OBSTRUCTIVE INTRAVASCULAR MRI COIL: IN VIVO MAGNETIC RESONANCE IMAGING OF EXPERIMENTAL ATHEROSCLEROSIS. SG Worthlev*. G Helft. M Shinnar. L Minkoff. ZA Favad, HMO Farouaue. IT Meredith. V Fuster. IT Badimon. Cardiovascular Research Centre, Monash University, Monash Medical Centre, Melbourne, Magna Laboratories, New York and the Cardiovascular Institute, Mount Sinai School of Medicine. New York. Acute coronary syndromes are the result of atherosclerotic plaque disruption and subsequent thrombosis. The composition of the atherosclerotic plaque, rather than its stenotic severity, is a critical determinant of both risk of rupture and thrombogenicity Magnetic resonance imaging (MRI) is being used to characterise the composition of atherosclerotic plaques. However, the resolution achievable using surface radio-frequency (RF) probes is limited by the signal-to-noise ratio. We studied the utility of a new intravascular (IV) MRI probe for high resolution in vivo imaging of atherosclerotic lesions. Balloon injured Watanabe Heritable Hyperlipidaemic rabbits were utilised. The newly developed IV MRI probe is 1.3mm in diameter, and can be positioned over a guide-wire. MR imaging was performed with both an external phased-array coil and the IV MR coil, using a clinical 1.5 Tesla MRl system (Signa CVi GE Medical Systems). After MR imaging, the animals were sacrificed and analysis of agreement between MR and histopathology performed, using both simple linear regression and Bland-Altman analyses. Images with the IV MRI coil were obtained with 156 x 156~ in-plane resolution, compared with 352 x 352~ with the external phased-array coil. No significant motion artifacts were noted, despite the continuation of arterial blood flow during image acquisition around the IV probe. Plaque components (lipid core, fibrous cap) were easily identified. There was an excellent agreement between MR imaging with the IV coil and histopathology, by simple linear regression for both the mean wall thickness (rz0.88, slope 0.82, p
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INACCURACIES IN ONE-DIMENSIONAL MIDWALL FIBER TRACKING FORMULAE DUE TO VIOLATION OF UNDERLYING ASSUMPTIONS. T.L. Gentles* B.R. Cowan. C. Occleshaw. A.A. Young Departments of Paediatric Cardiology and Cardiac Radiology Green Lane Hospital and the Departments of Physiology and Medicine Auckland University Background: Geometric midwall fiber tracking formulae using M-mode echocardiographic measurements have been used extensively to estimate midwall shortening in thick-walled ventricles. These formulae assume homogeneous LV shortening and calculate shortening from wall thickening using conservation of mass. Methods: Echocardiograms (ECHO) and MRl studies were undertaken in 15 young adults 17-23 years after repair of coarctation of the aorta (COA), and in 15 age, gender and body size matched control subjects. Circumferential midwall shortening fraction (MWSF) was calculated from M-mode measurements using the Shimizu formula. Long axis shortening (LASF) was backcalculated from assumptions underlying the derivation of the same formula. MWSF and LASF were directly measured by MRI tissue-tagging using a 3-dimensional finite element model. Results: The ECHO wall thickness to chamber dimension ratio was elevated in the COA group (0.18+0.02 vs 0.15?0.02, p
COA

MRI LASF

MWSF

0.214.03’ 0.17409 0 214.01 Control O.lGo.03 024.09 0 214x01+ ‘~~0.05 COA compared to control. ‘p
LASF 0.154.01’ 0.174.01

Conclusions: Measurement of midwall fiber shortening using one dimensional midwall tracking formulae may be inaccurate, due to violation of underlying assumptions. These findings have important implications for the assessment of shortening in normal vs hypertrophied ventricles.

COLOUR CODED REGIONAL MYOCARDIAL DISPLACEMENT ALLOWS SIMPLE AND ACCURATE DETECTION OF CORONARY ARTERY DISEASE DURING DOBUTAMINE ECHO. P Cain*, T Baelin, C Case, T Marwick. University of Queensland, Brisbane. Background: Accurate interpretation of dobutamine echo (DbE) requires prolonged training. Tissue Doppler permits a quantitative approach to DbE interpretation but interpretation of velocity profiles is inconvenient. Automated integration of the velocity profiles can measure regional myocardial displacement (RD, “tissue tracking”). The resulting color map may allow intuitive assessment of regional myocardial function and detection of coronary artery disease (CAD). Methods: 90 pts (68 men, age 63+25 y’s) including 20 pts at low pretest risk (LOW) and 70 pts with angiography (CATH) were studied with standard DbE. Significant coronary stenoses were defined by quantitative stenosis diameter >50%. Wall motion was assessed by an experienced reader. Peak stress images from 3 standard apical views were acquired in digital tine-loop format (GE Vingmed SV) and analyzed offline by a less experienced reader (Echopac ver 6.3b30) for regional myocardial displacement (RD), derived from the integral of tissue velocity in each pixel. Results: In the 20 LOW pts, segt displacements were summed in each territory and the normal range was identified as <20th percentile (see Table). The normal pattern showed a gradation of RD from base to mid to apex in 19 of 20 LOW pts (Figure). In CATH pts, reversal of normal base-apex displacement was a highly specific (90%) but insensitive (19%) CAD marker. Displacement correlated with wall motion (normal 7.2+3.6mm, ischemia 6.1+3.9mm, viability 4.5+3.0mm, scar 4.6+3.3mm, p
enced reader.

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3D AORTIC HAEMODYNAMICS LATE AFTER COARCTATION - MRI MEASUREMENTS AND COMPUTER MODELLING. KR Moyle. BR Cowan, GD Mallinson*, AAYounn, Cl Qccleshaw. Cardiac MRl Research Group, University of Auckland.

Heart,

REPAIR A Schenk , TL Gentle:.

Outline: MRl was used to measure the 3D blood velocity in the descending aorta of patients late after coarctation repair. A computer model was developed to assist in further understanding the abnormalities found. Methods: (a) 14 patients (aged 19-23) who had CoA repair 17-23 years previously, and 15 age-, sex- and BSA-matched normal volunteers (NV), were imaged with MRI. Flow data were acquired by phase contrast on each of 5 parallel 6 mm para-sagittal slices covering the ascending, arch and descending aorta to the level of the diaphragm. Typically 35 phases through the cardiac cycle were obtained. The data were processed to produce 3D unsteady velocity vector fields that which were then displayed by computational fluid dynamics (CFD) visualisation methods. @) CFD mathematical models of typical stenoses were created to investigate the relationship between stenosis size, shape, and orientation and the haemodynamics of the descending aorta. Results: As expected, flow downstream Stream lines from residual stenoses was characterised by a jet with higher than normal velocity In addition spiralling flow as shown by the stream lines in the figure was evident distal to the stenosis resulting from induced longitudinal vorticity. When this occurred it persisted for some time after the peak of the axial flow. While the jetting $pY is an obvious consequence of the narrowing and expansion of the flow passage through the stenosis, the CFD study indicated that spiralling flow occurred only Aorta when the passage through the stenosis distal to was inclined to the axis of the aorta. Use of stenosis these abnormal flow features alone allowed a medically inexperienced operator to identify all of the patients in the coarctation repair group (with two further false positives).

ABNORMAL SEPTAL WALL MOTION AND LEFT ANTERIOR DESCENDING DISEASE IN LEFI BUNDLE BRANCH BLOCK MAY BE DETECTED WITH QUANTITATIVE TISSUE DOPPLER. P Cain*, T Bae1in.L Short.T Marwick. University of Queensland, Brisbane. Background: Interpretation of septal ischemia in the presence of left bundle branch block (LBBB) is difficult during dobutamine echo (DbE). Quantitative measurement of myocardial function using tissue Doppler may offer a means of detecting left anterior descending (LAD) disease in these pts. Methods: 20 pts with LBBB (7 with angiography) and 20 controls matched by visual wall motion score (WMS) but without LBBB were studied. A standard DbE protocol was used. Rest and peak systolic velocities (PSV) and timing of peak velocities (TPV) were obtained in the basal septal and basal and mid anteroseptal sgts by post-processing of color tissue Doppler at each stage (GE-Viigmed 55). WMS at rest and peak stress were scored using a 16 segt model. Results: At rest and peak stress TI’V and PSV were significantly different in pts with LBBB compared to matched controls. In addition, PSV and TPV were significantly different in pts with LBBB according to septal WMS abnormality (Table). Compared with segts supplied by a normal LAD, those subtended by LAD stenosis showed lower PSV at rest (3.5-l.Ocm/s vs. 2.&1.5cm/s, p=O.45) and peak stress (8.6-1.7cm/s vs. 4.2-2.8cm/s, p=O.OOl). Table. Rest and peak septal TPV 61~4 and PSV (cm/s) by WM in LBBB(L) and contmls (‘3 Abnpeak p WMS N rest Abn rest p N peak WMS WMS WMS WMS 143r12 0.03 l&k69 247+104 0.001 109+15 TwL) 135k25 137*128 0.95 86*11 90+21 0.89 TwC) 0.001 0.03 0.01 0.07 P 0.04 Z.&l.8 0.4 6.9+4.3 4.7i3.7 3.7t1.6 FmL) 5.lM.2 0.001 4.2r0.5 3.7AO.7 0.01 7.2kO.7 BV(C) 0.18 0.1 0.08 0.04 P

Conclusions: Both PSV and TPV may offer an objective means of identifying abnormal WM and angiographic LAD disease in pts with LBBB.

Lung

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2001;

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LOW DOSE DOBUTAMINE TISSUE DOPPLER VELOCITY PREDICTS RECOVERY OF RESTING MYOCARDIAL DYSFUNCTION OVER FOLLOW-UP IN MEDICALLY TREATED AND REVASCULARIZED PATIENTS. l’ Cain’. C Case. B Haluska. T Marwick, University of Queensland, Brisbane. Background: The identification of viable myocardium during dobutamine echo (WE) is subjective and requires experienced interpretation. We sought whether use of tissue Doppler to quantify regional responses in pts with resting wall motion abnormalities (WMA) could predict improvement in function over follow-up. Methods: 44 pts (25 men, 54-14yrs)with resting LV dysfunction underwent DbE, with follow-up echo 6+5 months later. Revascularization (RVS) was performed in 34 pts (7 CABG, 27 PTCA), remaining pts were medically (MED) managed. DbE was performed using standard techniques with color tissue Doppler images of apical views acquired in digital cineloop format (GEVmgmed S5). Three independent interpretations were made; qualitative evaluation of WM at DbE, measurement of peak systolic velocity (PSV), and comparison of resting WM at rest and follow-up. Results: Change in regional l”SV between rest and low dose was greater in segts with viability defined as regional recovery over follow-up and as augmentation of WM at DbE. A biphasic vs a uniphasic response to DbE was associated with a more pronounced improvement in PSV at low dose compared to a uniphasic response (Table).

RVSWMS same RVS-WMS better P Med - WMS same Med - WMS better P

Biphasic ESpI”SE0.1 * 1.0 1.8 * 0.8 0.001

Uniphasic RSpllW2 0.2 + 0.8 1.0 t 1.0 0.05

All 0.1 r 0.9 1.5 * 1.2 0.04

0.2 + 0.6 1.8 * 0.9 0.001

0.4 + 0.4 1.5 + 0.7 0.04

0.3 * 0.5 1.7 A 0.8 0.001

Conclusions: Change in PSV at low dose DbE is an objective index of viability that correlates with improvement of segts with resting WMA due to viable myocardium.

MR IMAGING IN ASSESSMENT OF PULMONARY INCOMPETENCE FOLLOWING TETRALOGY REPAIR. SLS MacDonald’*. Cl Occleshawlz BR Cowanz. AA Youngz, I Skinne$‘ Cardiac Radiology’, Paediatric Cardiologys, Green Lane Hospital; Cardiac MR Research Group2, University of Auckland, Auckland. Background Tetralogy repair is frequently complicated by late development of pulmonary incompetence with subsequent impairment of RV function. MR imaging developments allow for non-invasive anatomical and functional assessment. Methods: 12 patients, age 13 - 41 years, 6 male, 6 female, were referred for assessment of clinically significant pulmonary incompetence following Tetralogy repair 12.4 - 34.5 years previously. Imaging was performed with a 1.5T Siemens Vision scanner with the patient awake. Breath-held, segmented k-space, gated tine images were acquired along the long and short axes of the RV, with subsequent analysis using customised software (CIM, University of Auckland) on an SGI 02. Tl-weighted, breath-held, segmented k-space anatomical images of the pulmonary arteries were also acquired, followed by flow studies in the MPA, Rl’A and LPA using a double-gating technique. Results: RV volumes were increased and function reduced with mean RVEDV 245 +/- 103mls, RVESV 163 +/- 82mls, RVSV 82 +/- 29mls, RV EF 35.2 +/- 9.0%. RV mass was 171 +/- 84g. Mean pulmonary artery diameter at the narrowest point was Ml’A 39mm (z-score = l.O), Rl’A 16mm (z-score = -2.4), LPA 1Omm (z-score = -4.6). Mean net pulmonary flow was 4.1 +/ - 2.0 l/mm, with a regurgitant fraction of 50 +/- 15%. Pulmonary flow distribution was abnormal with 67% to the right lung, 33% to the left lung. Discussion: MR imaging is able to provide objective measurements of RV function, pulmonary artery size and flow in patients presenting with complications of Tetralogy repair. The lack of exposure to ionising radiation and radiographic contrast media, and the non-invasive nature of this modality make MR imaging useful in this situation.

49th Annual Scientific Meeting of CSANZ

Heart, Lung and Circulation 2001; 10

ERRORS IN DEFINING END-SYSTOLE CAUSE SIGNIFICANT ERRORS IN ESV CALCULATION IN LV CARDIAC MRI ANALYSIS. BR C owd; AA You&. CT Occleshawz, S Thrupp’. M Bad. LT Dell’Italia3, ‘Cardiac MRI Research Group, University of Auckland, ‘Green Lane Hospital, Auckland, ?Jniversity of Alabama, Birmingham, USA. Background: MRl is an accurate method of evaluating LV function. Typically 15-25 images are acquired through the cardiac cycle, and one phase is subjectively chosen to represent end-systole by viewing a tine loop. ESV is then determined by summing the volume contained in each of the parallel short axis slices at that phase in the cardiac cycle. This study quantified the errors caused by selecting the wrong phase as end-systole. Methods: A total of 50 patients were imaged at 7 days and 3 months after their first myocardial infarct with 8 or 9 short-axis non-breathhold slices (Phillips 1.5 T, thickness=8mm, NEX=2, FOV=350-475mm). A standard clinical analysis was performed using the Mass program (version 1.0, University Hospital at Leiden) to determine ESV based on determining the volume of the phase selected to represent end-systole. The data was then reanalysed in a blinded fashion with the LV cavity volume calculated for all phases so that the phase of minimum volume could be determined. Results: The correct phase was chosen in only 36% of cases in the standard analysis. Selecting either one phase before or after the true end-systolic phase was the commonest error (40% cases), which introduced an error of 6% into the ESV. A further 25% of cases had much greater errors in ESV of 13% and 25% (see table). Phase selected

Correct phase

Percentage of case5 Error in ESV

+I-1 phase

36 %

+I-2 phases 18 s: 13 %

40 % 6%

+/-3 phases 6% 25 %

Discussion: The end-systolic phase cannot be reliably chosen by looking at short axis tine loops. This method introduces significant errors into the ESV calculation and therefore into the ejection fraction.

APEX TO BASE VARIATION IN TIMING OF END-SYSTOLE. BR CowanI*. AA You&. S Thruoo’. CT Occleshaw’. TL Gentles2 ‘Cardiac MRI Research Group, University of Auckland, Green Lane Hospital, Auckland End-systole is defined on a short-axis M-mode echocardiogram of the LV by selecting the point at which the endocardial surface of the interventricular septum is most posterior. In MRI, the end-systolic phase is usually determined by viewing a midventricular short axis tine, and making a subjective decision based on blood volume and wall thickness. This study sought to test the hypothesis that there was no variation in the end-systolic time (EST) determined from the apical and basal short-axis MRI images. Methods: 15 normal volunteers (10 male, age 18-32 years) were scanned by MR to produce 8-9 short-axis slices evenly positioned from base to apex. The temporal resolution between each phase was 4045 msec. The blood volume of every slice and phase was calculated and the phase of minimum volume for each short-axis slice was determined. Results: The EST occurred 2 phases (80-90 msec) earlier for the mid-ventricular slices than those at the apex or base (see graph).

CHANGES IN SYSTOLIC SHORTENING IN LV HYPERTROPHY CAN BE PREDICTED USING A SIMPLE CYLINDRICAL MODEL. BR Cowan~: AA Your&. TL Gentle&. ‘Cardiac MRl Research Group, University of Auckland, aPediatric Cardiology, Green Lane Hospital, Auckland Background: Left ventricular hypertrophy (LVH) is associated with altered systolic contraction. In particular increased endocardial and midwall shortening indices, ejection fraction (EF) and fractional shortening have been reported. Methods: A simple mathematical model of the LV was constructed to test the hypothesis that these changes are a result of simple geometric effects alone. The LV was modelled as a cylinder with uniform longitudinal shortening, and circumferential shortening which varied from a maximum at the endocardium to a minimum at the epicardium calculated using a similar approach used for echocardiographic midwall shortening. The model was then hypertrophied by increasing the epicardial radius and an optimisation performed to calculate new shortening by minimising changes from the normal LV reference (endocardial radius=25mm, epicardial=35.5mm). Results: The analysis showed that for a 20% increase in mass, endocardial shortening was increased by 6% (35 to 37.1%), midwall shortening decreased by 3.4%, (18.6 to 18%) and epicardial shortening decreased by 11.1% (10.4 to 9.2%). This represented an increase in the slope of the distribution of circumferential strain from endocardium to epicardium. EF was increased by 3.4% (64.1 to 66.3%) and longitudinal shortening decreased by 1.2% (15 to 14.8%). It was further shown that the longitudinal and circumferential shortening could be further normalised toward the normal LV values if the ventricle was allowed to dilate until a critical radius was reached where all contractions become identical to the normal model. For 20% hypertrophy, this occurred with an increase in the endocardial radius of 9.6% (25 to 27.4mm). Conclusion: Many of the systolic changes seen in concentric LV hypertrophy can be predicted using a simple cylindrical mathematical model. This supports the hypothesis that these changes are due to geometric effects rather than changes in intrinsic myocardial contraction.

INTEGRATION OF DOBIJTAMINE ECHOCARDIOGRAPHY INTERPRETATION WITH TISSUE DOPPLER: EFFECT ON THE ACCURACY OF NOVICE, EXPERIENCED AND EXPERT INTERPRETERS RB. Fathi*, l? Cain, S. Nakatani #. H. Yut. T. Marwick University of Queensland, Brisbane, Australia. # National Cardiovascular Center, Osaka, Japan, + Queen Mary Hospital, University of Hong Kong, Hong Kong Background: Qualitative interpretation of wall motion score (WMS) with dobutamine echo (DbE) makes the accuracy of this technique dependent on the experience of the observer, and also poses problems of concordance between observers. Tissue Doppler measurement of myocardial Doppler velocity (MDV) offers a quantitative technique for identification of coronary disease, but it is unclear whether MDV could improve the results of less expert readers and in segments with low inter-obsenrer concordance. Methods: Seventy-seven patients underwent standard DbE and coronary angiography. Images were acquired in digital format and scored by four novice readers, four experienced echocardiographers, and two experts in stress echocardiography. New or worsening abnormalities were identified as ischemia and resting abnormalities as scar. Segmental MDV was measured independently and previously derived cut-offs were applied to categorize segments as normal or abnormal. Five strategies were used to combine MDV and WMS, and the results of each reader using each strategy were compared to quantitative coronary angiography Resulh: Fifty-five pts had CAD. The accuracy of WMS by novice (68?3%) and experienced echocardiographers (71*3%) was less than experts in stress echo (88+3%, p
I

2 APBX

3

4 Slice

5 number

6

7

8

9

Base

Conclusion: The time of minimum blood volume in a short-axis slice occurs 80-90 msec earlier in the mid-ventricle than at the base or apex. The change in position of a single point of the endocardium is not necessarily an accurate indication of end-systole.

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Novice

MDV only

MDV +

ignore WMS

WMS apex

68 + 3 77 * 5” Experienced 71+3 77*5 Expert 88 + 3 77 + 5’ * = RO.05 from baseline accuracy

76 + 2’ 76 f 2’ 81 zt 3’

MDV

if

WMS ll0i?llal 75 * 2* 74 + 2 84+3’

MDV in basal segs 75 Yk2’ 76 + 2’ 85 + 3

Conclusion: Routine MDV integration improves the accuracy enced readers but not the expert stress echocardiographer.

MDV in basal segs if normal 76 -f- 2’ 74 * 2 86 f 3

of less experi-

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Heart,

THE EFFECT OF CD-ROM BASED TEACHING ON THE ACCURACY OF NOVICE AND EXPERIENCED READERS OF DOBUTAMINE STRESS ECHOCARDIOGRAPHY. RB. F&hi*. l? Cain, V. Khourv. 0. Naios. S. Yuda., A. Tavlor. S. Nakataniti. T. Marwick. Princess Alexandra Hospital, Brisbane, Australia. #National Cardiovascular Center, Osaka, Japan Background: Previous work with dipyridamole echo defined a learning curve before novice readers developed similar accuracy to experts, the increment of accuracy being from 60 to 80%. Subsequent development of dobutamine echo (DbE), digital image review and harmonic imaging led us to question whether this learning curve had changed. We assessed the influence of CD-ROM based training on the sensitivity and accuracy of novice vs expert readers in two centers. Methods: DbE with harmonic imaging was performed in 77 pts who underwent coronary angiography. Resting, low-dose (lOpg/kg/min Db) and highdose (4Opg/kg/min Db) images were acquired in digital format. Images were analyzed by nine (four novice, three experienced and two expert) independent observers; new or worsening wall motion abnormalities were identified as ischemia and resting abnormality as scar. The accuracy of each reader was obtained by comparing segmental scoring to quantitative coronary angiography. Non-expert readers underwent a CD-ROM based training course (120 studies) after which all scans were re-evaluated. Results: Fifty-five pts had CAD. The experts had similar accuracy (88%) to that recorded in earlier studies, but that of novices (68%) and experienced echocardiographers (72%) was greater than previously reported. After training, sensitivity of the novice readers improved from 74% to 90% (p
Read 1

Read 2

BASAL MID

0.233

0.301

0.394

0.433

0.21

APICAL

0.526

0.561

0.29

p-value 0.04

Conclusions: Despite improvement (probably related to technical advances) the pre-training accuracy of novice readers is still unacceptably low. A CDROM based course improved the concordance of novices and experts but did not significantly improve overall accuracy. Adequate accuracy may require direct teaching interaction that cannot be duplicated from a CDROM. DIRECT CURRENT CARDIOVERSION CAUSES REVERSIBLE VENTRICULAR SYSTOLIC DYSFUNCTION. [email protected]‘. H.C.Tanuz m-14, Departments of Cardiology, Concord Hospital’, NSW and Changi General Hospital*, Singapore; Deparhnent of Medicine, Sydney [email protected]; Heart Research Institute, NSW4. Background: Direct current cardioversion (DCC) is commonly used to revert atria1 fibrillation (AF) and atria1 flutter (AFL), and is known to be complicated by reversible contractile dysfunction (stunning) of the atrium. It is unknown if DCC exerts adverse effects on ventricular myocardium. The aim of this study was to evaluate whether ventricular stunning occurs as a result of DCC, using tissue Doppler imaging (TDI), a novel and sensitive Echo modality for measuring regional myocardial contractility. Method: 29 patients (24 with AF and 5 with AFL) for elective DCC were prospectively enrolled. Echo studies including TDI were performed before, immediately post DCC (84r5lmin[meanrSD], n=29), and on follow-up (27&29days, n=18). Digital images were stored on optical disc using Vingmed System 5, and analysed offline. Left ventricular ejection fraction (LVEF) was calculated from the average of 5 consecutive loops using Biplane Simpson’s Rule. Using TDI, peak systolic velocity (PSV, in cm/set) of 7 different myocardial segments were each measured from 5 consecutive loops and averaged. The segments were mitral annulus-medial (MAM), mitral annulus-lateral (MAL), basal lateral wall (B.Lat), basal septum (B.Sep), tricuspid annulus-medial (TAM), tricuspid annulus-lateral (TAL) and basal RV free wall (B.RV). Statistical analysis was performed using Student’s paired t-test. Results: In patients with AF (n=24), DCC caused significant acute reduction in PSV in B.Lat (4.1+2.0 to 3.3?1.9cm/sec, l’O.O5 for all pair-wise comparisons), and LVEF did not change (44.5+15.8% VS 45.1+_16.4%, P=O.84). On follow-up (n=4), there was a significant increase in PSV in B.Sep, MAM, B.RV, TAM and TAL (P
Lung

and Circulation

2001;

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AGITATED COLLOID IS SUPERIOR TO SALINE AND EQUIVALENT To LEVOVISTB IN ENHANCING TRICUSPID REGURGITATION DOPPLER ENVELOPE AND IN THE OPACIFICATION OF RIGHT HEART CHAMBERS H C Tan*‘,*, K Fung’, L Kritharides’j ‘Concord Repatriation Hospital, Sydney, ‘Changi General Hospital, Singapore, 3Heart Research Institute, Sydney Introduction: The Doppler spectrum of tricuspid regurgitation (TR) is used to non-invasively assess right ventricular pressure. With mild TR, the native (Nat) TR envelope often does not allow accurate pressure evaluation. Proprietary contrast agents such as LevovistB (Lev) augment TR Doppler but are expensive, and their efficacy has not been objectively evaluated in subjects with difficult baseline studies nor compared to less expensive saline (Sal) or simple colloid solutions such as GelafusinB (Gel). Methods: 29 consecutive patients with poor quality Nat TR envelopes on transthoracic echocardiogram were re-examined after serial intravenous injection of 3 contrast agents (Sal, Gel and Lev). Doppler signals for each agent were acquired onto Viigmed System V and recorded on video and digitally on optical disc. These were assessed for signal quality, estimated RV pressure, inter-observer and intra-observer variation, and longevity of signal. Of the 29, 12 patients underwent percutaneous right heart catheterization to independently evaluate the pressure estimates from echo. Right heart opacification was quantified usingAdobe Photoshop 5.5 to assess signal brightness (luminosity). Result: All three contrast agents significantly improved the mean quality grade (grades O-5) of TR envelopes (Nat 1.12, Sal 1.97, Gel 2.56, Lev 2.41, p
CAN ULTRASOUND STRAIN INDICES IMPROVE THE ASSESSMENT OF RADIAL AND LONGITUDINAL MYOCARDIAL FUNCTION? A STUDY IN NORMAL SUBJECTS. M. Kowalski*. L.A. Simmons. T. Kukulski. F. Iamal. 1. D’hooee. E Weidemann. B. Biinens. L. Hatle, G. R. Sutherland. University Hospital Gasthuisberg, Leuven, Belgium Aim: Radial and longitudinal regional 1-D strain (e) and strain rate (SR) can be measured by ultrasound data by determining the local in-plane spatial velocity (Vel) gradient. The aims of this study were to define normal segmental values for E and SR, to compare radial and longitudinal E/SR profiles, and to determine whether E/SR were homogeneous throughout the LV walls. Methods: High frame rate (>120 fps) color Doppler data sets were collected in a cineloop format from 40 normals (20-44 y; 11F) using standard parasternal (lax) and apical (4-, 3-, 2-chamber) views. Maximal systolic Vel, E and SR were processed off-line for both radial (basal posterior wall segment-pw) and longitudinal (septum, lateral, posterior, anterior walls) function. Longitudinal Vel and E/SR profiles were determined for basal, mid- and apical segments. All Vel and E/SR values were averaged over 3 cardiac cycles. Results: Radial &/SR were consistently higher than longitudinal. There was a Vel gradient (base-apex) found throughout LV walls. In contrast to this nonuniform Vel distribution, E and SR values were homogeneous (See table). Lax pw basal Vel(cm/s) SR(s/-1) E (“h)

4.31 -1.30 3.03 -0.76# 46-e

Apical 4ch sephxm basal midapical 5.69 -1.58’ 1.15 4x35 21-5

‘has vs mid- vs api p
4.27 -1.30 1.49 -0.35 21-5

3.06 -1.06 1.55 4.30 234

basal 6.39 -1.08’ 1.17 a33 15-5

Apical 3ch pw apical mid5.42 -1.21 1.23 -0.33 16-5

4.17 -1.43 1.24 4.31 18-5

radial vs longitudinal (basal) pw p
Conclusions: Ultrasound based 1-D E and SR indices can quantify local radial and longitudinal deformation. For longitudinal deformation they are homogeneous throughout the LV walls. For the acquisition and post-processing methods described, E and SR imaging is a robust and reproducible new technique ready for clinical use.

Heart,

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A127

THE FEASIBILITY OF REGIONAL STRAIN RATE/STRAIN IMAGING IN QUANTIFYING DOBUTAMINE STRESS ECHOCARDIOGRAPHY. M. Kowalski*, M.Ch. Herreeods. L. Herbots. L.A. Simmons, I. Strotmann, F. Weidemann. Ch.Dommke. I. D’hooee. B. Bijnens. L. Hatle. G.R. Sutherland University Hospital, Gasthuisberg, Leuven, Belgium

ASSESSMENT OF THE INCREMENTAL CLINICAL VALUE OF TRANSOESOPHAGEAL ECHOCARDIOGRAPHY IN PATIENTS WITH NATIVE VALVES AND SUSPECTED ENDOCARDITIS. M Lund’. F Louez-Timenez. OB da Silva. CY Ho. SD Solomon. Brigham and Women’s Hospital, Boston, USA.

Background: Quantification of Dobutamine Stress Echocardiography (DSE) is now feasible using Doppler Myocardial Imaging (DMI). Prior studies have determined the potential role of regional radial and longitudinal velocities in detecting an abnormal response. In theory, this may be better defined by local deformation indices: strain rate (SR) and strain (E) which are determined by measuring the local in-plane spatial velocity (Vel) gradient. Aim: The aims of our study were twofold: to determine 1) the percentage of segments, in which interpretable SR/E data could be obtained during DSE. 2) whether rapid heart rates influenced data analysis. Methods: DSE was performed in 12 pts. A standard 3-minute protocol was used. DMI velocity data were acquired at: baseline, low dose, peak dose and recovery. To evaluate radial function (basal posterior wall segment) parasternal LAX, SAX views were used. For long axis function data were acquired (4-CH, 2-CH views) from the septum, lateral, inferior and anterior walls. Data was acquired using both 15” and 45” sector angles. During post-processing each wall was divided into three segments: basal, mid and apical. SR/E values were averaged over 3 consecutive heart cycles. Results: The radial function data were analysed for 96 segments and longitw dinal data was analysed for 1152 segments. The number and percentage of segments which had to be excluded because of uninterpretable SR/E is shown in the table:

The optimal use of transthoracic (TTE) versus transoesophageal (TOE) echocardiography in evaluating patients with suspected endocarditis remains controversial. We aimed to investigate the incremental clinical value of TOE when compared to TTE alone in the diagnosis of native valve endocarditis. Methods: From January 1 1996 to November 30 2000,132 patients underwent a TTE followed by a TOE within 7 days for the evaluation of suspected endocard&. TIE studies were reviewed by 3 independent echocardiographers blinded to clinical and TOE data. TIE image quality was assessed using an objective 4-point scale. Patients were classified according to the Duke criteria into 3 groups: DEFINITE, POSSIBLE or REJECTED using bacteriological, echocardiographic and clinical data. Patients were classified twice, first incorporating TIE data and then incorporating the TOE data. The number of patients who were switched from one Duke group to another when the TOE results instead of the TTE data were used determined the incremental clinical value of TOE. Results: TOE was more sensitive than TTE for detecting abnormalities consistent with vegetations or abscesses even with excellent TTE image quality. When the TIE data was used to classify patients according to the Duke diagnostic criteria for endocarditis, 18 patients were classified as DEFINITE, 47 as POSSIBLE and 67 as REJECTED. When TOE results were used, no patient classification changed from REJECTED to DEFINITE, 6 patients (5%) changed from REJECTED to POSSIBLE, 5 (4%) from POSSIBLE to DEFINITE, and in 2 patients (2%) the diagnostic classification moved down from POSSIBLE to REJECTED. Conclusions: Despite the higher sensitivity of TOE when compared to TTE to detect vegetations, the final diagnosis of native valve infective endocarditis may not be importantly altered by TOE data in the majority of patients, when clinical and bacteriologic information is incorporated.

Radial SR/s Number and percentage of segments excluded

1(1.04%)

Longitudinal SRI& ~namow angle 159 6 (1.04%)

Longitudinal SRk (wide angle 15”) 20 (3.4%)

The majority of segments excluded were either in the anterior (13) or lateral wall (9). Rapid heart rates werr not associated with a reduction m interpretable segments.

Conclusions: This feasibility study would suggest that with appropriate data collection and post-processing methodology (including averaging of three consecutive beats) SR/e imaging can be applied to the quantification of DSE.

CONSTRUCTION OF PATIENT SPECIFIC TORSO AND VENTRICULAR GEOMETRIC MODELS FOR BODY SURFACE MAPPING OF VENTRICULAR ARRHYTHMIAS USING TRANSTHORACIC THREE-DIMENSIONAL ECHOCARDIOGRAPHY. G.B. Sands*. R.A. French, S. Withv, A.I. Pullan and M.E. Legeet. Department of Engineering Science, University of Auckland, and Department of Cardiology, Green Lane Hospital, Auckland.

ECHOCARDIOGRAPHIC CHARACTERIZATION OF DIASTOLIC FUNCTION IN FRIEDREICH’S ATAXIA USING TISSUE DOPPLER IMAGING. PM Mottram. RE Peverill. L Donelan. M Delatvcki. IS Gelman*. Centre for Heart and Chest Research, Department of Medicine, Monash University and Monash Medical Centre, Clayton, Victoria.

Body surface potential mapping (BSPM) is an experimental technique which may enable non-invasive localisation of ventricular arrythmias. However, accurate mapping of the origin of the arrhythmia depends on accurate modeling of the geometry and localisation of the left and right ventricles within the torso. The aim of this study was to determine the feasibility of using 3-dimensional echocardiography based on a magnetic position and orientation tracking system to generate patient specific geometric models of the left (LV) and right (RV) ventricles and torso in viva. 15 subjects were scanned in the supine position using a standard transthoracic ultrasound probe, performing 6-12 6 second sweeps of the left and right ventricles using pamsternal and apical views in held expiration. The 2D images were digitised and registered with position and orientation information from a receiver mounted on the probe which detects changes in the magnetic field strength generated by a transmitter beneath the patient, Fiducial marks on the patients torso were scanned before and after image acquisition to ensure that no movement had occurred. Tracing of LV and RV epicardial and endocardial borders, apices, and mitral, aortic and tricuspid annulae was then performed on ECG-referenced end-diastolic images using a customized tracing program which allows for interactive editing of the borders in 3D and generates separate 3D data sets for each cardiac structure of interest. Surface models of the LV and RV endo- and epicardium were produced within the torso by embedding a “host mesh” and aligning it to conform to certain “anchor points” from the 3D scan then deforming the surfaces to the 3D data. Patient specific torso models were generated by scaling a generic torso model to the measured fiducial marks. Endocardial surface and torso models were able to be produced in all cases. Problems encountered included poor coverage of the RV, patient movement, and poor endocardial definition in some views. However, sufficient accuracy has been demonstrated to localise pacing sites withii the interventricular septum. Conclusion: Construction of patient specific torso and ventricular models using 3D echocardiography is feasible, and may allow accurate localisation of ventricular arrythmias using BSPM. Further validation is necessary. Ultimately this technique could aid in selection and follow up of patients undergoing radio-frequency ablation of ventricular arrythmias.

Background: Friedreich’s Ataxia (FA) patients have a high incidence of hypertrophic cardiomyopathy, but diastolic function is poorly characterized in this group, with reports of both normal and abnormal diastology in the presence of left ventricular (LV) hypertrophy. We hypothesized that tissue Doppler imaging (TDI) (a load-independent measure of myocardial relaxation) would more accurately define diastolic function in these patients and differentiate normal from pseudonormal diastology. Methods: Ten consecutive FA patients (5 male; mean age 37.8+10.0 yrs) with normal LV systolic function and 10 matched controls underwent detailed echocardiographic diastolic evaluation including TDI at the medial and lateral mitral annulus. Results: FA patients had similar LV diastolic diameter but greater wall thickness at the septum (p
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Heart,

Lung

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2001;

10

THE TEI INDEX DISTINGUISHES PATIENTS WITH CARDIOMYOPATHY AND ADVANCED DIASTOLIC DYSFUNCTION WHO IMPROVE WITH THE VALSALVA MANOEUVRE. JJ. Pereira’, D.I. Prior, A. M Foe& er alah The Cleveland Clinic Foundation, Cleveland, Ohio, USA and St Vincent’s Hospital, Melbourne, Australia.

TROPONIN I FRAGMENTATION OCCURS MYOCARDIUM AND IS NOT RELATED TO POST FUNCTION. Pr n* H : Department of Medicine, University of Sydney, NSW

Objectives: Stratification of prognosis among patients (pts) with diastolic dysfunction with elevated filling pressures (DDEFP) is improved by examining the response to manoeuvres which decrease preload. We sought to determine if there were baseline indices that would distinguish pts with DDEFP whose diastolic staging improved with Valsalva manoeuver, from those with fixed patterns. Methods: We prospectively studied 43 pts in sinus rhythm with heart failure secondary to ischemic or dilated cardiomyopathy (CM) and left ventricular ejection fraction < 35%. Comprehensive echocardiographic examination including baseline values of early (E) and late (A) mitral inflow Doppler velocity, E wave deceleration time (DT), the Tei index (Tei) = (isovolumic contraction time plus isovolumic relaxation time) divided by systolic ejection time, lateral mitral annular velocities (S, E‘, A‘), mitral inflow velocity of propagation (VP) and response to the Valsalva manoeuvre was performed. Results: Nineteen pts classified at baseline by conventional criteria had DDEFP with a pseudonormal (stage 2) or restrictive filling pattern (stage 3 or 4). After Valsalva, 11 pts (Group 1) improved by at least one stage and 8 pts (Group 2) were unchanged. Baseline E/A DT(msec) Tei E’IA IYE WP Group 1 2.2 +1.4 159229 0.51 izO.16 3.3 20.9 1.2 r0.4 11.5 r4.4 Group 2 3.0 il.8 121 t39 0.97 to.27 3.4 ~~0.6 1.9 +0.9 13.0 i4.5 P NS 0.054 0.016 NS 0.07 NS

Background: We examined the hypothesis that proteolysis of troponin I (TnI) is the fundamental mechanism of myocardial stunning. Methods: Left ventricular (LV) samples were taken from freshly harvested rabbit hearts (Group I), after 90 mins Langendorff perfusion (Group II), after 15 mins low-flow (1 ml/min) &hernia (I) and 60 mins reperfusion (R) (Group III), and after 60 mins I and 6il mins R without (Group IV) or with L-arginine 200 mM (Group V). Isovolumic LV pressure was measured throughout and Western blotting for Tnl performed with 3 specific antibodies. Results: Irreversible myocardial injury (horseradish peroxidase stain) was observed only after 60 mins I / 60 mins R. Recovery of rate-pressure product after 60 mins R was greater in Groups III (56 2 9% of baseline) and V (66 f 7%) than in Group IV (23 * 9%, ~~0.05). In all groups, both intact TnI (29 kDa) and a 25 kDa fragment were detected by Western blotting with each antibody. Intensity of the 25 kDa band, relative to intact TnI, was 8.6 f 0.9% in Group I, 9.9 f 0.8% in Group II, 11.0 * 1.2% in Group III, 22.9 f 2.0% in Group IV (p
VdSdV.? Group 1 Group 2 r

WA 1.3 Al.0 2.8 k1.6 0.052

DTbnsec) 241~66 128 L28
E-IA‘ 1.1 AO.3 2.1 +0.5 0.021

WP 2.3 +0.9 2.9 i0.7 NS

IN NORMAL ISCHAEMIC DYSrem”.

WE 7.5 A4.4 10.3 zt1.9 NS

Conclusions: The Ml’1 at baseline can distinguish those pts whose diastolic staging will improve with preload reduction by Valsalva manoeuvre, a group previously shown to have a better prognosis. Both the Valsalva manoeuvre and Ml’1 may have prognostic and therapeutic implications in pts with CM and DDEFI?

SEVERE AORTIC ALLOGRAFI DYSFUNCTION: CHARACTERISTIC ECHOCARDIOGRAPHIC FEATURES. D Burstow. D Seaton*. G Scalia. ahman.RShameen.PPalka., ALa M O’Brien. The Prince Charles HosSR pital, Brisbane, Australia.

MIBEFRADIL IMPROVES CORONARY FLOW IN THE CORONARY SLOW FLOW PHENOMENON (CSFP). S.P. Turner’ , I.F. Beltrame, J.D. Cardiology Unit, North West Adelaide Health Service, University of Adelaide, SA.

Background: We have previously reported the prevalence and types of Aortic Allograft (AAllo) dysfunction in a large echocardiographic follow-up study of 615 patients which demonstrated a small but distinct subgroup who developed haemodynamically significant AA110 stenosis. The pathogenesis of this variability in AA110 dysfunction remains unclear. The aim of the current study was to document the characteristic 2D and Doppler echocardiographic features of AA110 stenosis and cornparr these features to AA110 with significant regurgitation. Methods: From the original study cohort, 42 patients (mean age 44yrs, 27 male) were identified with significant AAllo dysfunction; 9 with Grade 2 or 3 stenosis (AAlloS) and 33 with Grade 2 to 4 regurgitation and no associated stenosis (AAlloR). ZD/Doppler echocardiographic examinations were retrospectively reviewed and, in addition, a 2D valve score was calculated based on leaflet thickening (T), distribution of thickening (D), degree of calcification (C) and leaflet motion (M).

The CSFl’ is an angiographic findiig characterised by TIMIflow in the absence of significant epicardial coronary disease. Patients often present with an acute coronary syndrome. Mibefradil, a calcium T-zhannel blocker, is an effective anti-angina1 for this disorder. The objective of this study is to assess the acute angiographic flow response to mibefradil in vessels exhibiting the CSFP Ten patients (aged 36-56 years, 8 males) presenting with unstable angina and documented CSFl’ were administered 50 mg of mibefradil following baseline angiography. All patients were on maintenance verapamil, prophylactic nitrate and aspirin therapy. Heart rate (HR) and blood pressure were continuously monitored. Repeat angiography was performed 30 minutes later in the same projection and blinded off-line analysis of the TIMI-flow grade, corrected TIM&frame count (CTFC), and epicardial coronary artery diameters were performed by two independent observers. Mibefradil did not alter heart rate (AHR = -3 + 7%; p=NS), rate-pressure product (ARRP =-1 + 14% ,p=NS) or epicardial coronary diameter (Adiameter = 12 6%; p = NS) during the 30 minute observation period. Of the 18 vessels initially exhibiting TIMIflow, 13 improved to TIMIflow following mibefradil (see table). Furthermore the CTFC improved by 29 f 18% (p = 0.0001) in CSFP vessels following mibefradil, whereas there was no significant change in CTFC in vessels without CSFP (ACTFC = 9 * 23%; p = 0.06 vs CSFP vessels) Conclusion: Mibefradil improves the CTFC in vessels exhibiting the CSFP and may be potentially beneficial in this disorder. Selective improvement of flow would be consistant with the observed therapeutic impact.

Results:

The findings

are tabulated

below:

AVA Lesion Me.3n T Type Grad AAlloS 41’*14 1.2*+0.2 2.9*+0.8 AAlloR 12*7 2.3 f 0.9 1.6 f 0.7 * = P value
2D Score

Total

D

C

M

2.9**0.3 1.3 * 1.1

3.1’iO.6 1.6 k 0.7

2.3’+1.0 1.3 * 0.8

SCOE

11**2.2 5.8 it 2.8

As expected, AAlloS had higher mean gradients and smaller AVA values. Total 2D scores as well as valve sub-scores were significantly higher in the AAlloS group indicating more diffuse and severe leaflet pathology compared with AAlloR. Conclusions: AAlloS is a distinct form of AA110 dysfunction with characteristic 2D and Doppler features consistent with marked post-inflammatory valve injury and raises the possibility of a unique pathogenesis.

Response to Mibefradil Vessels with TIMI- Flow at Baseline (% of All Vessels.) Vessels with TIM-2 Flow After Mibefradil

LAD 9 (90%) 2 (20%)

CX 4 (40%) 1 (10%)

RCA 5 (50%) 2 (20%)

TOW 18 (60%) 5 (16%)

Heart, Lung and Circulation

49th Annual Scientific Meeting of CSANZ

2001; 10

ARE DELAYED RECANALIZATION OR REOCCLUSION OF THE INFARCT RELATED ARTERY INFLUENCED BY TIME TO THROMBOLYTIC THERAPY OR BY Q WAVES ON THE INITIAL ELECTROCARDIOGRAM? CK Won!?, HD White for the HERO-l investieators. Cardiology, Green Lane Hospital, Auckland, New Zealand Recent data suggest that with primary angioplasty, reinfarction was reduced, and mortality may be less affected by time from the onset of chest pain to treatment. It is unknown whether the late presenting patients with or without Q waves evolved fared worse after thrombolytic treatment because of lower recanalization and higher reocclusion rate. This study analyzed 288 patients with acute myocardial infarction who underwent both 90 minute and 48 hour angiography. At 90 minutes, TIMI 3 flow was more frequent in patients treated within 3 hours (63%) than in those treated from 3-12 hours (36%, p
DO TIM1 RISK SCORES PREDICT OUTCOMES AFTER ROUTINE CARE OF ACUTE MYOCARDIAL INFARCTION (AMI). J.M. Elliott*. 1.A. FalGoner. A.M. Richards Christchurch School of Medicine, Christchurch, New Zealand A recently published scoring system has been modelled and validated using data sets from randomised trials of treatment of AM1 patients presenting with ST elevation (STEMI)*. We have tested these risk scores in a New Zealand patient group by retrospective case note audit and one year follow up of all AM1 patients admitted to Christchurch Hospital from 1 Sept to 31 Dee 1999. Median age was 71 years, 42% women, 65% current or ex-smokers, 15% diabetes, 37% previous AMI. Of 91 patients with STEMI, 57% received thrombolysis or direct angioplasty; elective in-hospital angiography and angioplasty was performed in 26 and 16% respectively, 90% were discharged alive and 79% were alive at one year. The table shows 30 day and 1 year mortality in our patient group according to TIM1 risk score as well as predicted risk published by Morrow et al.* 30 Day and 1 Year Mortality All AMI (n= 219)

3% n = 22 0% 1 Year 5% (30 days) 2% et al, Circulation 2000; 1022031-7

STEM1 (n= 91)

Predicted’ *Morrow

30 Day 1 Year 30 Day

by TIM1 risk score’ O-2 3-4 n = 37 n = 36 0% 3% 8% n = 11 0% 0% 6%

EFFECT OF LOWER LIMB EXERCISE ON FOREARM BLOOD FLOW: CONTRIBUTION OF NITRIC OXIDE? D.T.Green: L.Mavaddat; C Cheetham: K.Watts*: M.Best: l.G O’Driscoll Department of Human Movement and Exercise Science, University of Western Australia, Nedlands, WA 6907; and Cardiac Transplant Unit, Royal Perth Hospital, Perth, WA, 6000 Background: During exercise, nitric oxide (NO) 1s released in the active tissue beds and contributes to vasodilation. However, there have been no studies of the possible NO release in inactive vessel beds during exercise. The purpose of this study was to test the hypothesis that blood flow to an inactive muscle bed, the forearm, increases during lower limb exercise, and to determine whether endothelium-derived NO contributes to any hyperaemic response which may be evident. Methods: Eight young, healthy male volunteers (age 22 + 4 [SD] yrs.) were random&d to participate in two studies, administered on separate days. Both studies consisted of two identical bouts of lower limb exercise separated by a 30 min rest period. Each exercise bout involved five three-minute incremental epochs (4OW, 6OW, 8OW, 1OOW and 16OW), performed on a bicycle ergometer. During one study, the bra&al artery was cannulated to allow continuous infusion of saline (60 ml/hr) during the initial exercise bout, and infusion of L-NMMA (8pmol at 6Oml/hr), an inhibitor of NO, during the re eat bout. The alternate study day was performed to provide a control for tE e effects of repeated exercise sessions, and did not involve an arterial cannulation or drug infusion. Throughout both studies, forearm blood flow (FBF) measures obtained from synchronised vascular ultrasound and Doppler were continuously recorded-at baseline, during all exercise bouts and for five minutes followine exercise. Results: FBF incrementallv increased in response to lower limb gercise. Blood flows were significantl$ higher at all exercise intensities when compared to baseline data (p
5-6 n = 66 8%

7-8 n = 50 14%

Z-8 n = 32 33%

Device

19% n = 24 4% 13% 14%

32% n = 20 10% 10% 25%

44% II=14 43% SO% 36%

noratec

This analysis demonstrated that a simple risk score that is predictive of 30 day mortality in a trial population is a robust predictor of one year mortality after routine care in New Zealand.

Al29

Thoratec Thoratec Heartmate Heartmate Heartmate

TM Intensity Pre LVAD km.hr-l/grade(%) 4.5/o 4/O 5/o 3/o NA 3.5/o

Initial TM Intensity Post LVAD km.hr-l/grade(%)

Peak TM Intensity Post LVAD kmhr-l/grade(%)

3/o 3/O 2/O 2/o

5.5/2 5.5/2

2/o 2.5/O

6/O

6/6 6/5 4/6

Factors that delayed or limited rehabilitation included driver problems, sepsis, haemolysis and pain associated with surgery and the implanted hardware, which were not specifically related to exercise. To date (27/01/01), 472 hours of exercise training have been performed without complications. Moderate intensity exercise training is safe and well tolerated in patients with LVADs. LVAD support enables patients with end-stage heart failure to improve exercise capacity while awaiting transplantation.

A130 49th Annual Scientific Meeting of CSANZ

CIRCULATING ACTIVIN A AND FOLLISTATIN ARE ELEVATED BY UNFRACTIONATED AND LOW MOLECULAR WEIGHT HEPARIN BUT NOT BY A DIRECT THROMBIN INHIBITOR. D J McGaw’*, A E O’Connor, S Hayward*, R W Harper’, D M de Kret&, D J Phillips2 & J J Smolich’. ‘Centre for Heart and Chest Research, Monash University, Vie; 2Monash Institute of Reproduction and Development, Monash University, Vie. Background and Aims: Activin A is a member of tbe transforming growth factor superfamily, which has been implicated in the processes of inflammation and atherosclerosis, and which is neutralised by the binding protein follistatin. Our previous studies have demonstrated that circulating activin A and follistatin levels are markedly elevated by administration of unfractionated heparin (UH) during cardiovascular procedures in humans. However, it is unknown if circulatory release of activin A or follistatin also occttrs after administration of low molecular weight heparin (LMWH) or direct tbrombin inhibitors, and if differing dosing regimes influence release patterns. Methods: To address these questions serial serum specimens were collected from chronically instrumented sheep via central venous catheters, before and after administration of anticoagulant (UH, LMWH or desirudin). Dosing regimes reflected clinical practice and included variable single intravenous (iv) doses, repeated iv doses, subcutaneous (s/c) doses and iv infusions. Results: Administration of iv bolus UH and LMWH caused rapid marked elevations in circulating activin A and follistatin. The release curves demonstrated a dose dependency and displayed a similar magnitude of response with repeated heparin boluses. Administration of LMWH via s/c route caused similar, but delayed release curves. Administration of UH via iv it&sion produced sustained elevations over 24 hours. In contrast, administration of desirudin did not alter the circulating levels of activin A or follistatin. Conclusions: The release of activin A and follistatin into the circulation by anticoagulants is specific to heparin, and occurs with both iv and s/c administration. This release demonstrates dose dependency, is of similar magnitude with repeated dosing and is sustained during continuous heparin infusion.

EFFECT OF POLYMORPHONUCLEAR LEUKOCYTES ON FIBRINO(GEN) DEGRADATION IN PLASMINOGEN KNOCKOUT MICE. Zene B’, Bruce D. and Brieeer D.B. Cardiology Department, Concord Repatriation General Hospital, University of Sydney, NSW, Australia Plasminogen knock-out (I’lg-/-) mice provide an unique opportunity for the study of alternative mediators of fibrinolysis. Polymorphonuclear leucocytes (I’MNs) contain non-plasmin fibrinolytic proteases, however the degree to which these cells contribute to fibrin(ogen) degradation in these animals is not known. Intact PMNs were elicited from the peritoneal cavities of Plg-/and wild type (Pig+/+) mice following 4% tbioglycolate stimulation. In vitro studies showed PMNs from Plg -/- mice to release greater quantities of 10% TCA soluble fibrinopeptides from I ‘“-labelled fibrinogen, than cells from Pig+/+ controls (at 72 h incubation: Pig-/- 918 ng / lo7 cells, Pig+/+ 589 ng / lo7 cells p=O.O05). The cell mediated degradation of I’rs-fibrinogen was not inhibited by the plasmin inhibitor aprotonin in either genotype. Furthermore, autoradiographic analysis of the 1’*5-fibrinogen degradation products showed the cleavage pattern by Plg -/- PMNs to be distinct from that produced by Plg +/+ PMNs. Tbrombi were generated in carotid arteries and jugular veins of Pig-/- and Pig+/+ mice following adventitial application of 20% Ferric chloride. PMNs, identified histologically on H&E staining and by immunohistochemistry using anti-mouse PMNs RB6-SC5 antibody, accumulated within the tbrombus by 6 hours after the injury and peaked at 24 hours. There was significantly greater retention of PMNs within the tbrombi of l’lg-/- mice from 48 to 72 hours than in the Pig+/+ controls (at 72 h: Pig-/- 580.8 + 185.1 cell/mm’ (n=5), Pig+/+ 148.3 + 29.8 cell/mm2 (n=5), p=O.O06 in the arterial thrombi; Plg-/- 548.8 r 179.5 cell/mm2 (n=5), Pig+/+ 273.7 + 106.9 cell/mm2 (n=5), p=O.O4 in the venous thrombi ) suggesting these cells to play a greater role in late fibrinolysis in Plg-/- mice relative to the wild type controls. In summary, these data suggest PMNs to play an enhanced role in fibrinolysis in the setting of plasminogen deficiency. In addition, these cells may do so via mechanisms distinct from those primarily responsible for the process in PMNs from wild type mice.

Heart, Lung and Circulation

2001; 10

THE EFFECTS OF ANDROGENS ON FOAM CELL FORMATION. M.K.C. Ne*. J.A. McCrohonS. Nakhla. W. Jessup. D.J. Handelsman and D.S. Celermaier. Department of Cardiology, Royal Prince Alfred Hospital, ANZAC Research Institute and Heart Research Institute, Sydney, Australia. Male sex ts an independent risk factor for atherosclerosis. We recently reported that androgen exposure increases foam cell formation in male but not female donor macrophages - a gender difference with implications for atherogenesis. In order to investigate the mechanism(s) for this androgen effect, a number of macrophage lipid uptake and trafficking experiments were undertaken. Methods: a) Scaveneer receptor binding and affinitv studies --- Male human monocytes obtained by elutriation were propagated for 8 days and exposed to either the androgen dihydrotestosterone (DHT at 400nmol/L) or vehicle control (ethanol 0.1%). Cell surface binding of modified (acetylated (AC)) LDL was assessed by measurement of cell-surface radioactivity after incubation with ‘*‘I-AcLDL; b) Retroendocvtosis (R) studies - Rates of R were measured following incubation with ‘*‘I-AcLDL by measuring the release of intact AcLDL into the extracellular media; c) Liooorotein untake and degradation studies - Macrophages were incubated with?-AcLDL and then cell associated plus degradation products were measured. Uptake was calculated as the sum of degraded plus cell-associated ‘r51-AcLDL. Results: There was no difference in receptor binding site number (1.35x 10~‘Omol/L in DHT treated cells vs. 1.23x10”emol/L in controls, P > 0.3) or binding affinity (Kd I.9lxlO~“mol/L in DHT treated cells vs. Kd 1.77x lO~*mol/L in controls, p>O.9) nor in retmendocytosis rates (100+5% and 10324% for control and DHT-treated cells respectively, p>O.l), between control and androgen treated cells respectively. Androgen treated male macrophages showed increased rates of AcLDL uptake and degradation by 45-75% after 15-20 hours of “SI-AcLDL incubation (p=O.OOl). Conclusion: Androgen exposure in male macrophages promotes increased processing of lipoprotein with more rapid lipid loading and cholesteryl ester formation. The intracellular mechanism may include increased lipoprotein internalisation and degradation, and/or induction of enzymes involved in cholesteryl ester processing and degradation.

THE EFFECTS OF DEHYDROEPIANDROSTERONE ON HUMAN MONOCYTE ADHESION TO VASCULAR ENDOTHELIUM AND FOAM CELL FORMATION. M.K.C. Ne*. S. Nakhla. W. Jessup. D.J. Handelsman and D.S. Celermaier. Department of Cardiology, Royal Prince Alfred Hospital, ANZAC Research Institute and Heart Research Institute, Sydney, Australia. Dehydroepiandrosterone (DHEA) is an adrenal sex hormone with weak androgenic action. Epidemiological studies report an inverse relationship between DHEA levels and cardiovascular mortality and animal studies report an inverse relationship with atherogenesis. The vascular biological effects of DHEA, however, are largely unknown. We studied the effects of DHEA on two key early events of atherogenesis: (I) human monocyte adhesion to vascular endothelium and (2) and foam cell formation. Methods: (I) Adhesion: Human umbilical vein endothelial cells (HUVECs) were grown to confluence and then exposed for 48 hours to either DHEA (I 2 ngiml or 120 rig/ml) or vehicle control (ethanol 0.1%). Human monocytes obtained by elutriation were incubated for 1 hour with HUVECs at 37’C, and adhesion was measured by haemocytometry. Surface expression of andothelial cell adhesion molecules (VCAM-I, ICAM-I and E-selectin) was measured by ELISA. Adhesion and CAM expression were assayed with and without interleukin 18 stimulation of the HUVECs. (2) Foam cell formation: Primary human male monocytes were allowed to differentiate into macrophages. Lipid loading studies were performed on macrophages treated with DHEA or control and, cholesterol (C) and its esters (CE) were Iuantitied by HPLC. By ANOVA, we compared control conditions with the effects of DHEA at both concentrations. Results: There was no significant effect of DHEA on monocyte-endotheltal adhesion (O.7), on endothelial cell expression of adhesion molecules (p>O.4 for all CAMS) or on macrophage C or CE accumulation (P>O.X). Conclusion: The adrenal androgen, DIIEA, has no direct effect on atherogenesis via monocyte-endothelial adhesion or via foam cell formation. 4s plasma levels of DHEA demonstrate a striking linear decrease with age, xevious epidemiological findings may be strongly confounded by Increasing atherosclerosis in older subjects.

Heart,

Lung

and Circulation

2001;

49th Annual

10

PROSPECTIVE STUDY OF THE EFFECTOF ANDROGENS ON SERUM INFLAMMATORY MARKERS. M.R.C. NE*. A.William$. S. PIakhla P. Liu L.Li. D.J. Handelsman and D S Cc lamaier. Daptinettts of Cardiology and Clinical hnmuaology, Royal Prince Alfred HospM, ANZAC Research Instihlte and Heart Research Institute, Sydney, Australia Androgcn replacement therapy (ART) is increasingly used in older men ta improve quality of life and muscle strength. We have previously shown that androgcns increase endothelisl cell VCAM-1 expression in vitro, a potentially pro-atherogenic change, and others have found that estrogens increase C-reactive protein (CRP) and other inflammatory markers. We lhereforc prospectively assessed the effects of andmgen replacement on serum CRP and soluble VCAM-I levels in sera of older men. @&ql& Two random&d double-blind placebo controlled trials were ilodertaken. In each study, healthy mere 60 years or older with low ~enxm testosterone levels (< I5 nmol/L.) were recruited and randomly assigned to receive placebo or androgen for 3 months. Two types of ART were assessed; the non-aromatisablc androgen dihydrotestostcrone (DHT). and recombinant human chorionic eonadotzoohin (rHCGI. which leads to production of bstolterotte and tb&ce smr&isation to CStrogenic metabolit&. TXbty three men completed the DHT trial (16 DHT and 17 c~ntmls) and 39 the rHCG trial (20 rHCG and 19 controls). Sera were collected from subjects at b.sselinc and at 3 months. High sensitwity CRP was measured by oephelometric immunoassay. Serum soluble VCAM-1 (sVCAM-I) was nearured by ELISA. w In both studies, groups were well matched for age and all vascular
PROGNOSTIC ASSESSMENT OF PATIENTS WITH CORONARY HEART DISEASE: RESULTS FROM THE LIPID STUDY. D. Col+oun. Wesley Medical Centre, Brisbane, I. Marschner, I. Simes, A. Keech. NHMRC Clinical Trials Centre, Sydney, P.Glasziou, University of Queensland, Brisbane We developed a risk-stratification strategy for prognostic assessment of patients with coronary heart disease (CHD). LIPID was a randomised, placebo-controlled trial assessing the efficacy of pravastatin over 6 years in 9014 patients with CHD and baseline cholesterol of 4-7 mmol/L. Data on 8557 patients were used to quantify risk. A multivariate risk-factor model was developed using the outcome of CHD death or nonfatal myocardial infarction (MI). In addition to the randomised treatment group, the following baseline characteristics were independently significant risk factors in the multivariate model: total cholesterol, HDL cholesterol, age, sex, smoking status, nature of CHD (MI or UA), prior revascularisation, diabetes, hypertension and prior stroke. On the basis of the magnitude of its adjusted relative risk, each risk factor was assigned risk points, and the aggregate risk score was calculated for each patient. Risk levels were defined by categorising the scores into quartiles. The predicted 5-year coronary event rates (%) for each risk level were: Placebo Pravastatin

low risk 5.8 4.6

medium risk 10.3 8.1

high risk 13.5 10.7

very high risk 20.2 16.1

Pravastatin therapy was associated with a significant reduction in coronary events across the range of risk levels. However, the absolute risk of an event was still high in treated patients with unfavorable risk factor profiles (table). Statin therapy unequivocally prevents recurrent CHD events. This risk stratification identifies patients at continuing very high risk. New’ treatment strategies need to be developed for these patients.

Scientific

Meeting

of CSANZ

A131

EFFECTS OF TESTOSTERONE ON ARTERIAL REACTIVITY IN HYPO-GONADAL MEN. M Sader*. K Griffiths. M Skilton. S Wishart, D Handelsman, D Celermaier. From the Departments of Cardiology, Royal Prince Alfred Hospital; Andrology, Concord Hospital; The Heart Research Institute; The ANZAC Research Institute and Department of Medicine, The University of Sydney, Australia. Atherosclerosis is more prevalent and severe in men than in age-matched women. Some evidence suggests androgens may be directly involved. Regarding vascular function, androgens are associated with impaired arterial reactivity in genetic females taking high dose androgenic steroids (AS) and endothelial function is enhanced in androgen-deprived older men, however the use of AS in bodybuilders is not associated with significant abnormalities of arterial structure or function. The vascular effects of physiological androgen replacement in otherwise healthy males, however, are not known. We recruited 9 hypogonadal males (age 35r3 years), on androgen replacement therapy, each receiving 800 mg testosterone depot preparations every 6 months. Four were smokers (1 current and 3 former), one had a history of hypertension on enalapril, and one a history of paroxysmal atria1 fibrillation on sotalol. None had a history of diabetes nor vascular disease and none were taking antioxidant therapy. Serum lipid and hormone levels and arterial reactivity were measured prior to (trough serum testosterone, T) and 2-4 weeks following testosterone administration (peak serum T). Each subject therefore served as their own control. Vessel diameter was measured by ultrasound at rest, during reactive hyperaemia (an endothelium-dependent response, leading to flow-mediated dilatation, FMD) and after sublingual nitroglycerin (GTN, an endothelium-independent dilator). Serum T increased significantly following subcutaneous depot T administration (13+6 nM v 27+9nM for trough and peak serum T respectively, pO.2). Hypogonadal men will not tolerate symptomatic androgen deprivation and so the degree of androgen “withdrawal” is much less than post-orchidectomy or of female baseline levels. This may contribute to the relatively modest vascular reactivity effect observed. Therefore in hypogonadal men, testosterone supplementation is associated with impaired endothelial function, independent of effects on lipid levels or blood pressure.

Lp(a) IS AN INDEPENDENT PREDICTOR OF CORONARY ATHEROSCLEROTIC BURDEN IN ASYMPTOMATIC MALES AND FEMALES. RGT Walker*. D.Grout, SM.Nidorf, S.Nair and PL ThomDson. Sydney Heart Image, NSW and West Australian Heart Research Institute, WA, Australia. Background: The role of Lp(a) in the development of atherosclerosis remains unclear. In part this relates to the inability to examine the potential influence of Lp(a) on the development of disease in a broad group of asymptomatic people who may otherwise have evidence of disease. Method: We used coronary artery calcium (CAC) screening (Toshiba, Aquilion) to detect coronary artery disease in 8590 asymptomatic people aged between 25-85, (64.6% men and 35.4% women). Mean plasma Lp(a) values for men and women were 0.36+0.38 and 0.40*0.45 respectively. Regression analysis was used to examine the predictors of the presence or absence of coronary artery calcium and age/sex matched CAC percentiles in men and women. Results: In men, individual age/sex matched percentile of coronary artery calcium score related independently to age (p
A132

49th

Annual

Scientific

Meeting

of CSANZ

Heart,

COMPARISON OF THE EFFECTS OF BEZAFIBRATE VS SIMVASTATIN ON THE ANGIOGRAPHIC PROGRESSION OF CORONARY ATHEROSCLEROSIS. CK Wane’. BI Webber, HD White. Cardiology, Green Lane Hospital, Auckland, New Zealand Both statins and fibrates are commonly used in patients with coronary disease, but there is no report of a direct comparison between the 2 groups of drugs. This study evaluated a Z-year treatment with simvastatin versus bezafibrate on the angiographic progression of coronary lesions. One hundred patients with coronary disease and hyperlipidemia were randomised to simvastatin 40mg daily or bezafibrate 4OOmg daily, and underwent baseline and 2 year quantitative coronary angiography. In the simvastatin group, the loss of mean minimum lumen diameter and the mean lumen diameter were 0.05 f 0.20mm and 0.02 r 0.22mm, which were less than the corresponding loss in the bezafibrate group (0.19 + 0.34 mm and 0.13 * 0.22mm, P
HYPERHOMOCYSTEINAEMIA IS INDEPENDENTLY ASSOCIATED WITH ARTERIAL DYSFUNCTION IN CORONARY PATIENTS. KS Woo’, P Chook. H’F Lao ILF Woo, DS Celermaier. The Chinese University of Hong Kong, Hong Kong and The University of Sydney, Australia. Background: Hyperhomocysteinaemia (HHC) is an independent risk factor for arterial endothelial dysfunction in asymptomatic adults, which improves with folic acid supplementation. Flow-mediated dilation (endotheliumdependent FMD) measured in the brachial artery correlates well with coronary endothelial function and prognosis. Methods: To evaluate the impact of HHC on arterial endothelial function in patients with coronary artery disease (CAD), we studied 94 non-diabetic patients with angiographically documented CAD. FMD and nitroglycerininduced dilation (endothelium-independent, GTN) of brachial artery were measured by high resolution ultrasound on 47 patients with high fasting total plasma homocysteine (HC) >=12prnol/l (39 males, 14 active smokers, mean age 58.5+/-8.2 years) and compared with 47 age, and gender-matched patients with normal HC (<12urnol/l). Results: The 2 groups were well matched for smoking status, body mass index, blood pressure, lipid profiles, glucose and coronary atherosclerosis score. The HHC group had higher creatinine and fibrinogen levels than those with normal HC. FMD but not GTN was significantly lower in HHC. On multivariate analysis, HHC (p= -0.37; p=O.O03), age (p= -0.35; p=O.OOS), glucose (j3= -0.29; p=O.Oll) and coronary atherosclerosis score (p= -0.27; p=O.O15) were independently related to FMD (model F=3.8; p=O.O003). Nomal HC (~mol/l) Creatinine (pmol/l)

Fibrinogen (g/l) PMD (%) GTN (%)

HC

8.2+/-1.5 91.7+/-18.4 3.4+/-0.7 6.1+/-2.0 15.5+/-3.5

HHC 15.8+/-4.8 111.6+/-34.6 3.9+/-1.0 4.2+/-2.2 14.5+/-3.9

p-Value <0.0001 0001 0.013 0.0001 0.20

Conclusion: Hyperhomocysteinaemia is independently associated with arterial endothelial dysfunction in CAD patients, providing possible explanation of association of hyperhomocysteinaemia with adverse late outcome after acute coronary syndrome.

Lung

and Circulation

2001;

10

FOLIC ACID SUPPLEMENTATION IMPROVES ARTERIAL ENDOTHELIAL FUNCTION IN HYPERHOMOCYSTEINEMIC CORONARY PATIENTS: A NOVEL SECONDARY PREVENTION STRATEGY. KS Woo*, P Chook. LLT Ghan. ASP Cheunrr. M Diao. PYK Peon. IE Sanderson. DS Celermajer. The Chinese University of Hong Kong, Hong Kong SAR and Royal Prince Alfred Hospital, Sydney, Australia. Background: Hyperhomocysteinaemia is an independent risk factor for arterial endothelial dysfunction and recently has been associated with poorer prognosis after acute coronary syndrome. Folic acid (FA) supplementation lowers homocysteine levels and improves endothelial function in asymptomatic subjects, but its impact on coronary subjects (CAD) has not been studied. Methods: The effect of FA on endothelial physiology was assessed in 22 angiographically documented CAD (age 59.2+/-5.1 year, 19 males, 6 smokers, total cholesterol 5.0+/-O.9mmol/l) with total fasting plasma homocysteine (tHcy) >12nmol/l. Each subject received oral FA (5mg/day) and placebo for 8 weeks using a randomized double-blind crossover design, with a washout period of 8 weeks. Brachial artery flow-mediated dilation (FMD, endothelium-dependent) and glyceryltrinitrate-induced dilation (GTN, endothelium-independent) were measured using high resolution ultrasound. Results: Compared to placebo, FA supplementation resulted in 4-folds increase of plasma folate levels (p
FMD (%) GTN (%) ( ‘comparing

Baseline Placebo 20.9+/-8.6 28.1+/-13.6 15.2+/-5.8 13.4~1.2.5 4.4+/-1.9 5.1+/-m 14.1+/-3.8 15.3+/-3.6 folic acid and placebo periods )

Conclusion: FA supplementation lowers blood arterial endothelial function in CAD, supporting coronary prevention.

Folic Acid 81.6+/-13.1 11.6+/-2.4 6.3+/-1.3 15.3+/-2.9

p-Value’ <0.0001 <0.04 <0.04

homocysteine its application

and improves in secondary

>0.5

JOB STRESS, WESTERNIZED DIETARY HABITS AND SUBCLINICAL ATHEROSCLEROSIS: REPORT FROM CATHAY STUDY. M Oiaol’, P Chookl, SLY Xul. BTY Lit&. SW Chanz, IZ Maiz. TZ Feng*, TLF Wool, TYK Ghan’. DS Celermaiers. KS Wo&-The Chinese University of Hong Kong’, The Chinese Hospital, San Francisco2, Pan Yu County HospitaB, Guangdong Provincial Cardiovascular Institute, China4, and The University of Sydney5. Background: Westernized Chinese in San Francisco have greater intimamedia thickness (IMT) of carotid artery as surrogate marker of atherosclerosis than rural Chinese in Pan Yu. Modem lifestyles in western countries have been incriminated, but the relative importance of job stress versus dietary changes have not been studied. Methods: To evaluate the impact of job stress versus dietary and other lifestyle risk factors on development of subclinical atherosclerosis, 297 asymptomatic employees of Chinese ethnic (mean age 43.4+10.1 year) from San Francisco, USA (n=187) and Pan Yu, southern China (n=llO) were studied. Carotid IMT was measured by high resolution ultrasound on both common carotid arteries, using an offline verified automatic edge-detection and measurement software package. Self-administered questionnaires on job stress (Karaseks job demand-control-support model) and daily food consumption (food catalogue album) were completed. Results: Age, smoking, excessive fat intake and lack of job support, but not carbohydrate or protein intake, were positively correlated to carotid IMT (~~0.05). On stepwise logistic regression analyses, apart from age, high fat product consumption and lack of job support were independently associated with increased IMT, while alcohol consumution was negatively , related: IMT Odds Ratio (95% CI) High fat consumption Lack of job support Alcohol consumption

1.14 (1.08-1.22) 5.66 (1.58-21.21) 2.77 (1.0-7.75) 0.17 (0.03-0.8)

pValLW 0.0001 0.008 0.05 0.027

Conclusions: High fat intake (from deep fried food and dairy products), and lack of job support are important independent risk factors for atherosclerosis in the Chinese, but alcohol consumption may be protective.

Heart,

Lung

and Circulation

49th Annual

2001; 10

REDUCTION OF MMP-1 AND -3 ACTIVITY IN THE WHHL RABBIT WITH ATORVASTATIN AND AVASIMIBE. SG Worthley*. R Corti. G Helft. tH aro u ith Bad’ on. Cardiovascular Research Centre, Monash University, Monash Medical Centre, Melbourne and Cardiovascular Institute, Mount Sinai School of Medicine, New York. The vulnerable atherosclerotic plaque has a pro-inflammatory cellular composition with increased levels of matrix metalloproteinases (MMPs). These enzymes are thought to be important in the process of plaque disruption. Thus the ability to modify these MMPs could be associated with plaque stabilisation. We studied the effects of lipid lowering (atorvastatin), alone and in combination with an ACAT inhibitor (avasimibe) in Watanabe Heritable Hyperlipidaemic (WHHL) rabbits. Atherosclerotic (AT) lesions were assessed with histopathology, including with staining for MMP-1 and -3. Induction of aortic AT was accelerated with balloon denudation in WHHL rabbits (age 3 months). Six months later, the animals were randomised into AT progression control (no therapy, n=3), AT regression with atorvastatin Smg/kg/day alone (n=3) and AT regression with atorvastatin Smg/kg/day and avasimibe 25mg/kg/day (n=3). This therapy was continued for six months. The effects of the different treatments on AT lesion progression were assessed by histopathology using vessel wall area (VWA) as a surrogate of atherosclerotic burden, and presented as mean&EM (mm2). Immunohistochemical staining for MMP-1 and -3 was performed, and expressed as a mean percentage of staining of the neo-intima. In combination with avasimibe, VWA was significantly decreased versus both controls and atorvastatin alone (2.31eO.03, p=O.Ol and p=O.OOl respectively). Control rabbits had a continued progression of AT after randomisation (VWA 7.16+0.03). Percent staining of the neo-intima for MMP-1 was reduced versus controls for both atorvastatin alone and in combination with avasimibe (17.4% vs 12.4% vs 5.8% respectively), although this was only statistically significant for atorvastatin and avasimibe in combination (p=O.O04). The extent of MMP-3 staining of the neo-intima was significantly reduced for both atorvastatin alone (p=O.O07) and in combination with avasimibe (43.4% vs 21.5% vs 27.4% respectively, p=O.O4) compared with controls. ACAT inhibition in combination with statins significantly retarded the formation of AT lesions in this model, and induced a significant modification of the MMP levels detected within the neo-intima.

Scientific

Meeting

ASYMPTOMATIC RADIAL ARTERY OCCLUSION CARDIAC CATHETERISATION VIA THE RADIAL kS Ni olls vascular Medicine, John Hunter Hospital, Newcastle,

of CSANZ

A133

IS COMMON AFTER APPROACH. G Trim*. Department of CardioNew South Wales.

Introduction: The radial artery approach for cardiac catheterisation has been promoted as an alternative to standard approaches due to perceived advantages such as ease of artery compressibility, and earlier mobilisation. Methods: We conducted a prospective clinical and ultrasound assessment of 25 consecutive patients in whom the radial artery approach was used. We documented age, gender, weight, whether the procedure was for diagnostic catheterisation or angioplasty, procedure duration, and dose of heparin administered. All patients had the Allen test performed pre-procedure to ensure adequate collateral flow to the hand in the event of radial artery occlusion. All patients were assessed clinically and by duplex ultrasound of the radial artery post procedure. Results: There were twenty males and five females, with an average age of 60. Thirteen had diagnostic angiograms and twelve had angioplasties. In three patients (12%) there was technical failure and cardiac catheterisation could not be completed from the radial artery. On duplex ultrasound examination post procedure, six (24%) had totally occluded radial arteries, two (8%) had partially occluded radial arteries, while in fourteen (56%) the radial artery was patent. All but one of the patients with occlusion had palpable radial arteries post procedure. The majority of radial artery occlusions (6 out of 8) were in diagnostic angiograms rather than angioplasty cases. Of the five female patients, three had total occlusions, one had partial occlusion, in one there was technical failure, and none had a complication-free procedure. Of the twenty male patients, however, fourteen (70%) had complication-free procedures Conclusion: While there were no clinical complications in those patients in whom radial artery catheterisation was performed, there was an unexpectedly high rate of asymptomatic partial or total occlusion of the radial artery post catheter&&ion, as assessed by duplex ultrasound.

COMPARISON OF ZD4522 TO PRAVASTATIN AND SIMVASTATIN IN THE TREATMENT OF PATIENTS WITH PRIMARY HYPERCHOLESTEROLEMIA. R.l H. Southworth? 1 Pears? ‘University of Milan, Italy; 2AstraZeneca, Cheshire, UK

LOW MOLECULAR WEIGHT HEPARIN INCREASES FEMORAL PSEUDOANEURYSMS AFTER CARDIAC ISATION. Guna B. lin m* S.Fa d P.R D.W. Muller. Cardiology Unit, St. Vincents Hospital, Sydney

Background: ZD4522 (rosuvastatin) is a new statin that has demonstrated potent, dose-dependent LDL-C lowering effects of up to 65% in clinical trials. This randomized trial compared ZD4522 with pravastatin and simvastatin to evaluate lipid effects and achievement of NCEP LDL-C goals. Methods: A randomized, double-blind trial in 502 patients with primary hypercholesterolemia (LDL-C 2160 and ~250 mg/dL; TG MOO mg/dL). Following a 6-week dietary run-in period, patients received ZD4522 5 or lOmg, pravastatin 20mg or simvastatin 20mg daily for 12 weeks. Results: after 12 weeks

Low molecular weight heparins are now widely used for the treatment of Acute Coronary Syndromes. While their therapeutic efficacy is established, the risk of bleeding complications is not well documented. This study sought to identify the incidence of femoral pseudoaneurysms after cardiac catheterisation at our institution, and investigate the effect of enoxaparin use on this incidence. The clinical course of 3 499 consecutive patients were reviewed after cardiac catheterisation procedures over a 2 year study period. Retrospective analysis of 2 161 patients revealed a femoral pseudoaneurysm incidence of 1.7%. Univariate analysis was used to identify independent predictors of pseudoaneurysm formation by comparing 39 pseudoaneurysm patients with an age and sex matched control group of 79 patients. Enoxaparin within 48 hours (p=O.O007), peripheral vascular disease (p=O.O015), enoxaparin post procedure (p
Treatment zD4522 5mg (n=120) ZD4522 1Omg (n=115) Pravastatin 20mg

LDL-C -42”,C

Change from baseline P/d HDL-C TC TG +h -3lF -12

Apo B .33%6

Apo Al +7

.49”k

+7

.34&b

-18

.39%b

+5

-28

14

-20

-13

-21

+4

-29

+4

(n=137) Simvastatin 2Omg -37 14 -26 -14 (n=130) “p
Conclusion: 5 and 1Omg ZD4522 are superior to boih 20mg pravastatin and 20mg simvastatin in lowering LDL-C, TC and Apo B. In addition, more patients achieved NCEP target LDL-C levels with ZD4522 at either dose compared to pravastatin and simvastatin. All treatments were well tolerated.

THE RISK OF CATHETER-

A134

49th Annual

Scientific

Meeting

of CSANZ

Heart,

Introduction:

gradient

and structural

assessment

of patients

BAL, C N

(MVG,

mmHg)

by continuous

wave

Doppler

as well as left atria1

area (LAA, cm2), and right ventricular systolic pressure (RVSP, mmHg) were obtained. Each patient’s baseline measurements acted as t=O data. All data is expressed as a percentage decrement from the baseline measurement. Results: Patients aged 47&15yrs (range 14-79yrs) who were followed for 34i22 months post-PMV. Immediately post-PMV, MVA was 1.54k45cm2 and MVG was 6.4+3.2mmHg. There was no statistically significant deterioration in MVG or MVA over the follow-up period - See figure. LAA and RVSP also remained stable. 50

Conclusions: In this intermediate-term follow-up of patients following percutaneous mitral balloon valvuloplasty, valve area and valve gradient remain stable. This data attests to the clinical durability of this procedure in the intermediate-term. Examination in the long term remains a priority in these patients.

LEFT VENTRICULAR PUNCTURE FOR THE PATIENTS WITH AORTIC AND MITRAL VALVE MASSACHUSETTS GENERAL HOSPITAL EXPERILV STICK.1989-2000. Walters DL*. Sanchez PL, M. Colon-Hemandez PI and Palacios. IF. Cardiology General Hospital, Harvard Medical School, Boston.

The haemodynamic

2001; 10

Background: Percutaneous balloon mitral valvuloplaty (PMV) is now the standard for management of isolated mitral stenosis (MS) in most patients. The long term durability of the hemodynamic results remains to be shown, Patients: Data was reviewed from 241 pts undergoing I’MV from 1991 to 2001. Patients were selected by having complete echo data immediately postPMV (Baseline) and at least on follow-up study 26 months later. Mitral valve area (MVA, cm2) ,calculated by pressure half time and planimetry, and mean

Background: The use of stents during percutaneous intervention is increasing. In recent years 2.5mm stent designs have become available. There are few data on the incidence of target lesion revascularisation (TLR) following deployment of 2.5mm stems. Aim and methods: To assess the need for TLR in patients treated with a stent of 2.5mm diameter at our institution between 01/01/99 and 29/02/00, a retrospective review of our interventional database and clinical records of all qualifying patients was performed. Results: 145 stents were implanted in 113 patients (74 male, 39 female). The mean age was 62 + 11 years (range 33 to 85 years) and diabetes mellitus was present in 15%. Stents used were: ACS Guidant 41%. Biodivysio SV 35%, NIR 19% and Jo stents 5%. The mean stem length was 14.3 f 5.Omm (range 8 to 32mm). Inflation pressure at implantation was 13.8 f 3.4atm (range 8 to 24atm). The LAD was treated in 39%, RCA in 12%, Circumflex in 16% and branch vessels in 33%. Aspirin was administered on a continuing basis and clopidogrel or ticlopidine administered for at least 2 weeks in all cases. Ahciximab was administered in 3 1% of stent procedures. Procedural success was 99% with post procedure TIM1 3 flow in 97% and TIM1 2 flow in 3%. During the follow up period of 16 f 4 months (range 10 to 24 months) the incidence of TLR was 13.1%. Acute closure occurred in 2%, subacute closure in 1.4%. and late closure 1.4%. In each case of closure percutaneous revascularisation was successfully performed. All cases of acute closure were in the proximal LAD as compared to no case for all other vessels (P = 0.056). TLR for restenosis was performed in 8.3% (9 PTCA, 3 CABG) at a mean time of 4.3 f I .9 months. Conclusions: Deployment of 2.5mm stents is safe with an acceptable rate of TLR. There appears to be a higher incidence of acute closure when the proximal LAD is the stented vessel. This may be due to poor stent apposition secondary to undersizing of the stent in relation to actual vessel size.

ASSESSMENT OF PROSTHESES: THE ENCE WITH THE Rodriauez-Alemoarte Division, Massachusetts USA.

and Circulation

EXCELLENT LONG TERM RESULTS FROM PERCUTANEOUS LOON MITRAL VALVULOPLASTY. M C Adsett*. D I Burstow Aronev G M Scalia. The Prince Charles Hospital. Brisbane, Australia.

TARGET LESION REVASCULARISATION AFI’BR STENTING IN SMALL CORONARY VESSELS A.P. Whelan*. G.T. Wilkins. M.P. McCormick. M.J.A. Williams. Department of Medicine, University of Gtago, Dunedin, New Zealand

TRANSTHORACIC

Lung

with

prosthetic valves may be difficult by non invasive methods. Accurate assessment is important as m-do surgery carries a significant risk. The technique of direct, percutaneous left ventricular puncture (LVS) is required for invasive haemodynamic assessment in patients with prosthetic valves in both the mitral and aortic positions. The aim of our report was to describe our experience with this infrequently used technique. Methods: Between January 1989 and December 2000, 31 patients were referred to the cardiac catheterisation laboratory for haemodynamic assessment via LVS on 33 separate occasions. The average age of the patients was 64 years (range 38-82), 14 (45%) were male and all had access to the left ventricle limited by valvular prostheses in both the aortic and mitral positions. Multiple prior cardiac surgical procedures had been performed in 19 (61%) of patients (range 1-4, mean 2) One of the patients also had a prosthetic tricuspid valve and two had tricuspid annuloplasties. All patients were referred for congestive cardiac failure (NYHA Class III or IV), with suspected mitral valve dysfunction in 20(61%), aortic valve disease in 3(9%) and both in 10 (30%). In all cases transthoracic or transesophageal echocardiography had been performed prior to the LVS. Oral anticoagulation and intravenous heparin was discontinued prior to the procedure. LVS was performed using a 5.5 Fr x 15cm trocar and pigtail catheter according to the standard technique. In addition all patients had inserted a pulmonary artery catheter, a transeptal puncture and an ascending aortic pigtail catheter. Results: Immediate procedural success was obtained in all cases. In 23 of 33 (70%) cases additional information was obtained over noninvasive assessment, In 17 (52%) cases this prompted cardiac surgery. In 10 (30%) cases invasive assessment confirmed the echocardiograph findings. The most frequent reason for a failed non-invasive assessment was the under estimation of mistral regurgitation and the faihne to appreciate paravalvular leaks in 13 of 23 (57%). Patients were followed until death or discharge from hospital. No patient died as a result to the procedure. Complications attributable to LVS occurred in 3(9%) patients with a hemo-pericardium requiring drainage percutaneously in one patient, another had a hemotborax requiring thoracotomy and decortication with repair of the puncture site and the remaining patient developed VF and a local hematoma. Conclusions: The technique of LVS carries low incidence of major complications in patients with multiple valve replacements. It provides important information that often dictates the surgical management of this complex patient group.

SAME DAY PERCUTANEOUS CORONARY DELAY? S. Trivedi’, C. N. Aroney. Cardiac Brisbane, Queensland.

INTERVENTION Unit, Prince Charles

. . . WHY Hospital,

Introduction: Patients who are considered at low risk for complications after percutaneous coronary intervention (PCI) may be suitable for same day discharge from the hospital. This may be particularly applicable when PC1 is performed using radial artery access. Methods: We retrospectively analysed 100 consecutive patients who underwent radial access PC1 at our institution over a period of 18 months. The radial artery was cannulated with a 6F sheath and patients were given 300mg of both aspirin and clopidogrel and 10,000 units of heparin which was adjusted if necessary to achieve an ACT of 300 seconds. Patients considered unsuitable for same day discharge included those with a history of unstable angina within 24 hrs, severe co-morbid conditions, administration of GP IIb/IIIa blockers, and those who had the procedure performed late in the day Also excluded were patients with other procedural high risk features including sidebranch occlusion, persistent or prolonged pain or ECG changes. The sheath was removed immediately after PCI. The decision to discharge was delayed until they underwent 4 hours of observation provided they remained free of symptoms and had no ECG changes. At discharge they were treated with dual antiplatelet therapy for 4 weeks and given instructions in the event of bleeding or chest pain. Results: Among 100 consecutive patients undergoing radial PC1 we discharged 33 low risk cases on the same day. 31/33 patients had single vessel PC1 and 29/33 had stent implants. The LAD was the target vessel in 16/33 patients and 26/33 were type B or C lesions. Reference vessel diameter was >3mm in all cases. No patients having early discharge had any complications or readmissions at either 24 hours or 30 days. Conclusion: In selected low risk patients same day discharge appears to be safe, particularly after radial access ICI. Suitable patients can be selected using simply applied criteria after a short period of observation.

Heart,

Lung

and Circulation

2001; 10

TRANSCORONARY ABLATION OF SEPTAL HYPERTROPHY - PRELIMINARY ACUTE RESULTS. A.M. Harris’. D.T. Burstow. C.N. Aronev. Cardiac Unit, Prince Charles Hospital, Brisbane, Queensland. Transcoronary ablation of septal hypertrophy [TASH] is a new technique for the treatment of patients with refractory symptoms due to hypertrophic cardiomyopathy. Methods: The procedure was performed under local anaesthesia with premedication with morphine and midazolam and the use of a temporary pacing wire. The left ventricular outflow tract gradient (LVOTG) was assessed using two catheters (a multipurpose catheter in the LV apex and the angioplasty guiding catheter) at rest and after provocation with ectopics or dobutamine. A 2mm over-the wire balloon catheter was positioned into the 1st Septal perforator and inflated and contrast injected through its lumen to ensure that there was no reflux of contrast into the LAD. 2 ml of Levovist, an echo contrast agent, was injected through the balloon catheter and transthoracic echocardiography was used to confirm localisation to the interventricular septum and not to the lateral wall of the left ventricle. Ethanol was then injected into the septal perforator, the LVOTG remeasured, protamine administered and the sheaths removed. Results: Five patients with severe (class III-IV) refractory symptoms [angina in 4 and dyspnoea in I] were treated. 2.5 - 4 ml of ethanol was injected. The maximal provocable LVOTG fell from a mean of 109 to a mean of 7 mmHg and the resting LVOTG fell from a mean of 39 to a mean of 6 mmHg. One patient developed complete heart block which was managed with permanent dual chamber pacing but there were no other complications. The average creatine kinase and troponin I levels were 1377 and 36 U/l respectively. Patients were discharged an average of 3.6 days (range: 2-5 days) after the procedure. All patients had a marked reduction or complete resolution of symptoms. Conclusions: TASH can be performed under local anaesthesia guided by transthoracic echocardiography. The procedure led to a significant acute reduction in LVOTG and marked improvement in symptoms.

ACUTE MYOCARDIAL INFARCTION ASSOCIATED WITH IN-STENT RESTENOSIS: INCIDENCE, OUTCOMES AND MANAGEMENT. D L Walters’. S A Hardine. IK-Kvunz lang. Cardiology Division, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA. Introduction: Stenting is the most likely choice of local therapies for the treatment of vulnerable plaques. Recent studies suggest that 5.8-17 % of patients who develop restenosis may present with acute myocardial infarction (AMI). The incidence of acute myocardial infarction associated with restenosis in the stent era has not been well characterised. The aim of this study was to assess the incidence of AM1 resulting from in-stent restenosis, patient outcomes and management. Methods: Between 10/l/97 and 10/31/00 6,000 patients underwent catheterisation at Massachusetts General Hospital. 318 consecutive patients with recurrent ischemia and restenosis were identified: 246 patients with in stent restenosis and 72 treated with percutaneous interventions (PCI) without stenting. AMI was defined according to ACC/AHA Criteria requiring evidence of an elevated biochemical marker preferably troponin or CK-MB. Patients who underwent PC1 in bypass grafts and those who developed acute stent thrombosis (representations within 30 days ),were excluded from the study, Results: A total of 38 (15%) patients (pts) presented with AMI associated with in-stent restenosis. ST elevation AMI (STEMI) occurred in 16 (42%). All patients were initially treated with heparin and aspirin. Thrombolysis was administered to 6 pts with STEMI and was successful in 5 (83%) with TIM1 2 2 flow at angiography. None of these patients received a Glycoprotein IIB-IIIA inhibitor (IIB-IIIA). 3 of these subsequently underwent PCI, 2 had CABG and 1 was medically managed. A IIB-IIL4 was used in 14 pts with all proceeding to PCI. In 6 cases IIB-IIIA were started prior to PCI. At angiography 5 (83%) had patent vessels. PC1 was performed in 27(71%) pts with 7 (18%) CABG and the remainder managed medically, PC1 consisted of balloon angioplasty (PTCA) alone in 10(37%), rotational atherectomy/PTCA 6 (22%), stenting 9 (33%), rotational atherectomy/stenting 1(4%), and directional atherectomy/stenting 1 (4%). For the entire group the mean peak CK rise was 1007 (range 127-7817). Intra-aortic balloon pump was required in 5 (13%) pts with 3 (8%) presenting with cardiogenic shock , and 2 with VF arrests. From the total group 36 (95%) pts were discharged home, one was placed in a nursing home and one died. Conclusion: AM1 as a result of in-stent restenosis occurs in 15% of cases of clinical restenosis and may be treated successfully with thrombolysis or PC1 Major adverse events (death, CABG or cardiogenic shock) are not infrequent.

49th Annual

Scientific

Meeting

PERCUTANEOUS TRANSLUMINAL SEPTAL TION FOR HYPERTROPHIC OBSTRUCTIVE PRELIMINARY RESULTS OF HAEMODYNAMIC hev. SC Wart 1 * PM Mottr Cardiovascular Research Centre and Department Medical Centre, Melbourne.

of CSANZ

A135

MYOCARDIAL ABLACARDIOMYOPATHY : EFFECTIVENESS. of Cardiology,

Monash

Percutaneous transluminal septal myocardial ablation (PTSMA) has emerged as a promising non-surgical technique for the reduction of left ventricular outflow tract gradient (LVOT) and symptomatic improvement in patients with hypertrophic obstructive cardiomyopathy (HCCM). We describe our intial results including 6 week follow-up data with this procedure in our first 5 patients. Myocardial contrast echocardiography (MCE) and ischaemic wall motion abnormality with balloon inflation were used to assist the selection of the appropriate septal branch. Absolute alcohol (2-3 mLs) was used to obtain septal artery ablation in all cases. Baseline transthoracic echocardiographic data was obtained in all patients, including post-valsalva LVOT gradient and stress echo (dobutamine or exercise) data, and were repeated within 2 weeks post-procedure, at 6 weeks and at 6 months. All demographic data is presented as mean+SD, and all echocardiographic data as mean&EM. Paired data sets were analysed using students t-test, with a statistical significance taken at a p value of ~0.05. Three men and two women underwent the procedure for severely symptomatic HOCM, refractory to medical therapy (age 50.5+13.1 years). The LVOT gradient post-valsalva was significantly reduced from 90.0+12.2mmHg to 51.4+16.7mmHg post-procedure (p=O.Ol) with a further reduction at 6 weeks to 27.2+16.0mmHg. Similarly, the resting LVOT gradient was significantly reduced from 46.6+14.5mmHg to 17.6*6.4mmHg post-procedure (p=O.O3) which persisted at 6 weeks (19.6+12.8mmHg). There was no significant difference in LV internal diameter (diastolic) at 6 weeks (4.65+0.39cm vs 4.38+0.35cm, p=NS). One patient required permanent pacemaker insertion for persistent complete heart block. There were no deaths. These preliminary serial data on the use of PTSMA in the described setting suggest it is a feasible and relatively safe technique. Ongoing studies and long-term follow-up data is still required for this procedure.

EPICARDIAL LEADS; IS STEROID ELUTION AN ADVANTAGE? K.A. Searancke*. F. Riddell. A. Kerr. K. Finucane. T.R. Skinner. Green Lane Hospital, Auckland Purpose: To retrospectively compare the pacing and sensing thresholds and frequency of exit block of steroid-eluting (SE) passive fixation (PF) and nonsteroid-eluting (NSE) active fixation (AF) epicardial pacing leads. Method:Between October 1988 and November 2000, 127 leads (104 SE, 25 NSE) were implanted in 65 patients (39 male) aged 3 days to 71 years (yrs) (median 3.5yrs). From December 1993 SE PF leads became available and were implanted as first choice where possible, however NSE AF leads were implanted when deeper myocardial penetration by an AF lead was required in order to pace through fibrotic tissue. A retrospective review of pacing implant and follow-up data was carried out. Results: Duration of follow up was 2 weeks - 7yrs (median 1Syrs) for SE leads and 2 weeks - lfyrs (median 2.5yrs) for NSE leads. Pacing thresholds in NSE AF leads at implant were 2.1V *3 and peaked at 6 weeks: 3.9Vr2.8, remaining higher than SE PF leads throughout follow-up in surviving leads; 2.3V*1.4 at 2.5 yrs; 2.7V+2.3 at 4 yrs. Pacing thresholds in SE PF leads at implant were 1.7V +- 1.5 and remained stable: lVkO.4 at 6 weeks; 1.4V-tl.2 at 2.5 yrs; 1.4V*O.6 at 4yrs. There was no significant difference in the ventricular sensing thresholds of SE PF and NSE AF leads throughout the follow-up duration. Exit block occurred in 5.7% of SE PF leads and 47% of NSE AF leads (p=O.OOl) with 57% of the NSE AF exit block occurring within 1 year of implant. Conclusion: Steroid eluting epicardial leads maintain lower pacing thresholds and have a reduced incidence of exit block. We recommend the use of an SE PF lead as first choice. However NSE AF leads are still required in a small number of cases.

A136

49th Annual Scientific Meeting of CSANZ

Heart, Lung and Circulation 2001; 10

SUCCESSFUL LONG TERM PERFORMANCE OF STEROID-ELUTING ACTIVE FIXATION LEADS IN THE ATRIUM AND VENTRICLE. S Corcoran. MBBS#mDas.. R Sutherland, RN’. H Mond, MD&*. #Department of Cardiology, The Royal Melbourne Hospital, Victoria, Australia and ‘Cardiac Rhythm Solutions, Australia. The successful use of steroid-eluting active fixation leads in the atrium is well documented. The performance of such leads in the ventricle is less well documented. With the advent of pacing from alternate sites, there has been a resurgence of interest in the use of active fixation leads in the ventricle. We compared the chronic performance of Pacesetter 1388T steroid-eluting active fixation leads in the atrium (A) and right ventricular (V) apex. In each patient identical 58cm leads were used in the atrium and ventricle. Telectronics META DR 1256 or TEMPO DR 2102 pulse generators were used. Thresholds (Thr)(voltage at 0.5ms pulse width), impedances (W), P and R waves were documented at implant, within 24 hours post-implant and at 1, 3 and 6 months. At follow-up P and R waves were determined when possible from the recorded intracardiac electrograms with the pacemaker programmed to DDI 30/min. Results: 40 patients, 20 male. Mean age 76 years (range 59-89). Indications:16 sick sinus syndrome, 22 high degree AV block, 2 unexplained syncope. Implant via cephalic vein in 56%. Atria1 fibrillation/flutter occurred at implant in 2 patients and post-implant in 3 patients precluding the collection of some atial data. There were no lead complications. Results given as mean t standard deviation, A Thr (V)

v Thr (V) r wave R WaYe AW VW

Implant 0.9 f 0.4s 0.7 A 0.3 2.9 * 1.2 13.2 r 6.8

1 month 0.7 f O.l#

3montbs 0.7 f 0.3x

6montbs= 0.7 r 0.2~

0.8 * 0.2 2.6 + 1.3 7.4 + 2.0

0.8 * 0.3 2.3? 1.1 6.9 + 2.1

0.9 + 0.2 2.7 + 1.1 7.7 k 2.3

504 * 113 435 k 50 674 * 162 510 zt 67 * 24 patients only # p < 0.05 compared with ventricular

444~63 524 * 89 threshold.

420 + 48 SG9r90

Conclusion: Steroid-eluting active fixation leads perform well in the atrium and ventricle with no complications and maintenance of pacing thresholds of less than 1Volt at 6 months. Performance is comparable to tined steroid-eluting leads in both chambers.

LONG-TERM EFFECTS OF PRAVASTATIN ON ENDOTHELIAL FUNCTION IN ADULTS WITH CORONARY ARTERY DISEASE. K.A. Griffiths*, A.C.< Emberson PT. Harris. A.M. Tonkin. D.S. Celermaier. Depts. of Cardiology and Clinical Biochemistry Royal Prince Alfred Hospital & NHMRC Clinical Trials Centre, University of Sydney The LIPID study enrolled 9014 patients with known coronary disease, random&d to pravastatin 4Omg daily or placebo for a mean of 6.1 years, and showed a significant clinical benefit from lipid lowering in these subjects, with reductions in heart attack, unstable angina, stroke and death. In order to explore the mechanism of benefit, we studied arterial endothelial function by ultrasound in a subset of 100 randomly selected patients enrolled at our study site. Each had bra&al artery reactivity tested at their last study visit, prior to treatment “unblinding”, after an average of 6 years of trial medication. Of the 100 subjects, 91 had technically satisfactory scans for blinded analysis (placebo 42, pravastatin 49). Groups were well matched for age (median 57, range 50-63 years), gender (89% male) and coronary risk factor profile. Over half of each group had had a coronary revascularisation procedure. These subjects were statistically similar to the overall LIPID study group. Wilcoxon tests were used to examine the effect of treatment on each variable flow-mediated dilatation (FMD, endothelium dependent), glyceryl trinitrateinduced dilatation (GTN, endothelium independent) and vessel size (v.size). No significant differences were detected. Variable FMD (%) GTN (“fo) VSIZE (mm)

Placebo 3.1*0.7 14.8e1.2 3.5*0.1

These data suggest that the substantial tatin in patients with CAD am primarily by improving vascular reactivity.

Pravastatin 2kO.5 14.7*1.0 3.420.1

p-value 0.99 0.94 0.66

clinical benefits of long-term pravasmediated by mechanisms other than

NECK TUMOURS PRESENTING AS AN UNUSUAL AND POTENTIALLY TREATABLE CAUSE OF SYNCOPE. S Nicholls*. G Trim, W Saw, P Leitch. Department of Cardiovascular Medicine. John Hunter Hospital. Newcastle, New South Wales,

IMPORTANCE OF CHOLESTEROL LOWERING IN HIGH-RISK INDIVIDUALS WITH IMPAIRED FASTING GLUCOSE, DIABETES AND DYSLII’IDAEMIA. A.C. Keech”. D Colauhoun. E.M. Belier. I Best, P Young, R Bradfield. NHMRC Clinical Trials Centre, University of Sydney

The diagnosis of syncope can often be difficult with investigation often unrewarding. A series of three patients with syncope secondary to tumour masses involving the neck are reviewed. (1) A 69 year old man with previous resection of an oropharyngeal squamous cell carcinoma presented with recurrent syncope. Examination revealed a left sided neck mass with the development of complete atrioventricular dissociation and hypotension upon palpation of the mass. Magnetic resonance imaging revealed a mass in the region of the carotid sinus. The mechanism of syncope was thought to be via carotid sinus hypersensitivity. The patient proceeded to permanent pacemaker implantation and combination radiation and chemotherapy. (2) A 76 year old man presented with recurrent postprandial syncope preceded by a burning sensation in the left side of the throat. After a 6 week hospital stay including pacemaker implantation, 2 tilt tests, coronary angiography and electroencephalography the diagnosis was established by computer&d tomography of the neck. Subsequent examination revealed subtle cranial nerve palsies consistent with a left sided jugular foramen syndrome. Nasoendoscopy revealed a nasopharyngeal mass. Biopsy revealed squamous cell carcinoma. The mechanism of syncope was thought to involve a reflex circuit involving the glossopharyngeal and vagus nerves. Permanent pacemaker implantation did not reduce the frequency of syncope. The patient proceeded to combination radiation and chemotherapy with reduced frequency of syncope. (3) A 47 year old man with a history of adenoidal cystic carcinoma, treated with surgical excision and radiation therapy presented with recurrent presyncope. Examination and investigations were unremarkable. The mechanism of syncope was thought to involve carotid sinus hypersensitivity secondary to the effects of radiation therapy. Conclusion: Dysfunction of various vascular and neurological structures in the neck due to tumour masses or the sequelae of their treatment can result in presyncope and syncope, Neck hunour masses should be considered an uncommon but potentially treatable cause of recurrent sync~pe and presyncope.

The LIPID study enrolled 9014 patients with known coronary disease (CHD), random&d to pravastatin 40mg daily or placebo for a mean of 6.1 years. It included many more patients with diabetes (1076). impaired fasting glucose [IFG] (941) and dyslipidaemia (HDLc 1.7mmol/L; 6454) than any previous statin trial, providing an opportunity to explore the comparative advantages of treatment on major outcomes of non-fatal and fatal coronary events, stroke and total mortality. Results: Absolute vascular risk in those with diabetes compared with normal fasting glucose was increased by 62-175%, and by S-50% with IFG, despite similar baseline lipid levels. Overall effects of pravastatin were similar on CHD events and death, but restricted to those with abnormal FG for stroke (pdO.01): Effect of pravastatin treatment on outcome (hazard ratios): Outcome CHD events Stroke Death *pP
Normal FG 0.77***

IFG 0.65’

Diabetes 0.80

0.94 0.79***

0.58 0.67’

0.61’ 0.80

Dyslipidaemia was also an important determinant of the benefits of pravastatin the entire benefit of pravastatin on stroke was restricted to those with dyshpidaemia, even among those with normal FG (p=O.O03 for heterogeneity): Effect of pravastatin treatment on stroke (hazard ratios): Outcome Normal FG FG Diabetes

Normal lipids 1.08 1.22 1.M)

Low HDL or high TG 1.32 0.38 0.78

Low HDL & high TG 0.54 0.65 0.40

Diabetes, IFG and dyslipidaemia all increase the absolute risk for vascular events, resulting in larger absolute risk reductions from pravastatin treatment. The greatest benefits of treatment on stroke are seen in those with both diabetes and dyslipidaemia.

Heart,

Lung

and Circulation

2001;

49th Annual

10

Scientific

Meeting

A137

of CSANZ

IMPORTANCE OF PROLONGED FOLLOW-UP IN SHOWING THE BENEFIT OF CHOLESTEROL-LOWERING TREATMENT PRAVASTATIN IN SUBGROUPS OF PATIENTS WITH CORONARY HEART DISEASE (CHD): THE LIPID TRIAL. J. Simes’. D. Hunt. S. Mulrav, A. Kirby, l’. Newman, A Tonkin, for the LIPID studv investieators, NHMRC Clinical Trials Centre, Sydney, and National Heart Foundation, Melbourne

CHOLESTEROL-LOWERING THERAPY IS MORE COST-EFFECTIVE FOR OLDER THAN YOUNGER PATIENTS: RESULTS FROM THE LIPID STUDY. A.M. Tonkin.’ National Heart Foundation, Melbourne, J. Simes, A. Kirbv, S. MulraK NHMRC Clinical Trials Centre, Sydney, H. White Green Lane Hospital, Auckland, P. Glasziou. Herston Medical School, Brisbane, on behalf of the LIPID investigators.

LIPID (NEJM 1998; 339: 1349) showed highly significant reductions in CHD mortality and CHD events with 6 years of pravastatin, versus placebo, in 9014 patients with prior CHD and average baseline total cholesterol (4.0-7.0 mmol/L). The relative treatment effects wasere similar for predefined subgroups, but there were too few events in important subgroups to show separate significant reductions, in particular for women, the elderly (>70 years) and those with total cholesterol ~5.5 mmol/L. The LIPID cohort has now been followed up for a further 2 years, with 85% of patients in each of the original randomised groups taking pravastatin treatment. This showed sustained and additional treatment benefit for patients originally assigned pravastatin.

The prevalence of coronary heart disease (CHD) in the elderly is high, as are its costs. We compared the costs and the effectiveness (in terms of lives saved and life years gained) for patients assigned pravastatin 40 mg/day with those for patients assigned placebo in subgroups aged 65-75 and aged 31-64 years at baseline in the Long-Term Intervention with l’ravastatin in Ischaemic Disease (LIPID) study.

Group CHD mortality

Main trial RRR (95% CI)

Plus extended follow-up RRR (95% CI) P

Fl?lll& Age >70 Total cholesterol ~5.5 All patients CHD events ICHD death Female Age >70

20 (-21 to 48) 0.29 14 (-16 to 36) 0.32 18 (-3 to 36) 0.09 24 (12 to 35)
31 (2 to 52) 19 (-5 to 37) 19 (1 to 34) 24 (14 to 34)

0.04 0.11 0.05 <0.0001

16 (-8 to 35) 20 (1 to 35)

0.17 0.04

Total cholesterol ~5.5 All patients

27 (1 t<, 46) 24 (15 to 32)

24 (1 to 41) 22 (14 to 29)

0.04 <0.0001

P

0.04 <0.0001

With extended follow-up and additional CHD events there is now clearer separate evidence of a treatment benefit in these important subgroups. size of these treatment effects is consistent with estimates for all patients.

and The

PRAVASTATIN REDUCES MAJOR CORONARY EVENTS IN PATIENTS WITH LOW LEVELS OF BOTH HIGHAND LOW-DENSITY LIPOPROTEIN CHOLESTEROLS (HDL-C, LDL-C): THE LIPID STUDY. D. Colauhoun*. I. Marschner. 1. Simes. I? Glasziou. A. Keech, H. White. l? Barter, A. Tonkin. for the LIPID Studv Investigators. NHMRC Clinical Trials Centre, University of Sydney, and National Heart Foundation, Melbourne Many patients with coronary heart disease (CHD) have low levels of HDL-C and LDL-C. We assessed the efficacy of pravastatin in preventing CHD in patients with low HDLC and low LDL-C. Of the 9014 patients in LIPID, 2463 fulfilled the lipid entry criteria of the VA-HIT trial: HDL 30 mg/dL, LDL 5140 mg/dL, triglycerides 5300 mg/dL. The efficacy of pravastatin was assessed and results were compared with those from gemfibrozil in VA-HIT. Patients had average baseline lipid levels similar to those of patients in VAHIT. Baseline differences included sex (LIPID, 81% men; VA-HIT, 100%) and diabetes (LIPID 8%; VA-HIT 25%). In both studies, HDL was 6% higher in the active arm at 1 year; LIPID had larger LDL differences (28% vs 0% lower in active arm) and smaller triglyceride differences (12% vs 31% lower in the active arm). Pravastatin significantly reduced major CHD events in this LIPID subgroup (log-rank P=O.OOl), with a relative risk reduction of 27% (95% CI ll-39), compared with 22% (95% CI 7-35) with gemfibrozil in VA-HlT. Trial LlPID (6 years) LIPID (5 years) VA-HIT (5 years)

CHD events: placebo (%I 16.8 14.3 21.7

CHD events: drug (%I 12.3 10.8 17.3

Absolute risk reduction (%) 4.5 3.5 4.4

Conclusion: This post-hoc subgroup analysis showed pravastatin therapy similar to that in the overall LIPID similar to that from gemfibrozil in VA-HIT.

Relative risk reduction W 27 24 22

a risk reduction with cohort and apparently

Age 314 Cost category Hospitalisations

b1=5500) Cost difference

-897

Medication Other costs Pravastatin TOTAL Cost-effectiveness parameter Life expectancy (years)

-354 148 4989 3886

Age 65-75 (~3514) per patient (5) -2061 -362 -23 4792 2347

18

Deaths averted/lOMl Life years saved/patient $ per life year saved

9 44

21 0.38 10900

0.40 4900

Estimates of cost differences and measures of effectiveness were derived from the two subgroups separately. Older patients assigned pravastatin had greater cost savings from fewer hospitalisations, resulting in a greater cost-offset of treatment. Among older patients, more lives were saved per 1000 treated (44 v 21), but life expectancy of survivors was projected to be less (9 years v 18). Because of the greater absolute risk of events and reduction in costs of hospitalisation in the older patients, pravastatin therapy is even more cost-effective for older patients.

DETERMINANTS OF NEW STUDY 3 YEARS APART IN FL Thomuson*. PI Bradshaw, Institute (Sir Charles Gairdner

CAROTID ARTERY PLAQUE ON REPEAT A RANDOMLY SELECTED POPULATION. 1 Hung. BM McQuillan. WA Heart Research Hospital Campus) Nedlands WA.

We examined 777 subjects aged 27-77 years at baseline and at 36months for cardiovascular risk factors, measured carotid intima-medial thickness and recorded the presence of carotid plaque. At baseline 24 % of subjects had plaque. Of the 589 who had no baseline plaque, 43% developed new plaque at 36 months. The univariate associations with the development of new plaque for continuously distributed risk factors are shown in the following table. New plaque mean * sd Age (years) Systolic BP mmHg Diastolic BP Total cholesterol mmol/L LDL cholesterol Triglycerides Cholesterol ratio Fibrinogen Smoking -pack years Ferritin Homccysteine

In multivariate

analysis

male sex (OR 2.6 95%CI

No plaque mean f sd 46.7+ 10.7 121* 14 78 + 9.4 5.25 + 0.99 3.3 _f 0.88 1.15 f 0.67 4.14i1.5 2.57+ 0.62 7.3 + 13.9 4.46 il.06 2.38*0.31

54.2 + 10.6 128k17 81 + 9.8 5.69 f 0.88 3.74 + 0.82 1.37 r 0.71 4.62 t 1.4 2.79 t 0.66 11.5 f 19.1 4.67 2 0.89 2.43 + 0.27

age (5% increase 1.6, 2.2) were

risk per year 95%CI

significantly

associated

2P
1.03, 1.07) and with

the risk of

developing plaque (
A138

49th Annual

Scientific

Meeting

of CSANZ

Heart,

COST EFFECTIVENESS OF CARDIAC REHABILITATION AFTER AN ACUTE CORONARY EVENT: A RANDOMISED CONTROLLED TRIAL. mBriffa*., R. Heath’. L. Donaldson2.P.Harris’~*. A. Keech. NHMRC Clinical Trials Centre, Royal Prince Alfred’ and Concord* Hospitals, Garvan Institute of Medical Research3, Sydney. Introduction: The cost effectiveness (CE) of cardiac rehabilitation (CR) needs to be better quantified, despite its apparent international acceptance based on enhanced quality of life and lower health resource utilisation. This study assessed incremental costs, changes in QOL, health resource utilisation and secondary prevention measures at one year after an AM1 or UAP treated with CR or conventional care (CC). Methods: One-hundred and thirteen patients aged 41 to 75 years were randomly assigned to CC or CR and provided details of rehabilitation, hospitalisations, medication use, outpatient visits, investigations and QOL. Data were verified using medical records, hospital databases and general practitioners. Resources are presented in 2000 dollars after valuation according to DRG, government and commercial schedules. Results: The estimated CE ratio for CR was $34,B46/QALY, or $16,17S/QALY gained after correction for published mortality benefits. Sensitivity analysis for the cost/QALY gamed ranged from $4,257 to not being implemented at any cost if rehabilitation were truly detrimental to QOL. Incremental benefit in QALY with CR measured by the Utility Based Questionnaire-H(eart), was 0.013 (on a scale O-l); p=O.36. Costs for the CC and CR groups were not significantly different ($216,191 versus $242,010; p=O.59). The incremental cost of rehabilitation was $453/patient. Over 12 months, fewer than one in five patients achieved the recommended goal for total cholesterol (3.5 mmol/L), hypertension (1140/90 mmHg), energy expenditure (>800 kcal/week), and 47% of smokers at the time of the index event remained smokers. Conclusions: The estimated CE of CR is justifiable in comparison with other acceptable health care treatments. Irrespective of rehabilitation every patient remained at excess risk for recurrent coronary events related to inadequate control of risk factors. Different cost efficient models of delivery of cardiac rehabilitation, more effective at achieving desirable health outcomes are needed.

AUDIT OF SECONDARY PREVENTION EASE PATIENTS. S. Bunker?~2~3. ‘National Heart Foundation of Australia, & Dohme (Australia). 3La Trobe University,

IN

CORONARY

Melbourne, Bundoora,

Victoria. Victoria.

HEART DISS. Rosenhair?. *Merck, Sharp

Control of modifiable coronary risk factors (CRF) in patients who have coronary heart disease (CHD) has been demonstrated in clinical trials to reduce mortality and further cardiac events. However, studies overseas have shown that CRF management is often sub-optimal in everyday clinical practice. The aim of this ongoing audit is to provide feedback to cardiologists, general practitioners and cardiac rehabilitation (CR) staff on the adequacy of CRF management and compliance in CHD patients following hospital discharge. Method: a convenience sample of CHD patients, identified from hospital or CR program records, were invited to attend CRF screening clinic. Where available, CRF status was compared between hospital discharge and followup and CR attenders and non-attenders. Results: Data obtained from 1966 patients (males=72%; females=28%; mean age=65.2+10.3 yrs) from 25 sites across 6 states in Australia. Mean length of time between index event and follow-up = 16 months. At follow-up 38% of patients with total chol. > 5.5 mmol/L were not prescribed lipid lowering agents. Total chol. was the only CRF found to have improved significantlv between discharee and follow-up (from 5.3Oz.2 to 4.44r0.98mmol/L, p=<.OOOl). Risk factor % at screening A lower total chol. and Current smoker 18 increased amount of exercise were the only significant facSBP>140mmHg & DBP>90mmHg 25 tors distinguishing CR attenTotal cholesterol > 4.0 mmol/L 57 ders from non-attenders. Total cholesterol > 4.5 mmol/L 38 Conclusion: Even in a sample Total cholesterol > 5.5 mmol/L 14 of self-selected, and presum29 HDL 27 47 patients, considerable potenSedentary 50 tial exists for further Diabetes 15 improvements in CRF status.

DOES ENDOTHELIAL DYSFUNCTION ANGINA? C. Edwards* Ramananthan.R.A.H. K. H.D. White. Green Lane Hospital, Auckland,

Lung

and Circulation

EXPLAIN New

2001;

10

POST-PRANDIAL

Zealand.

Background: A meal rich in cooked fat has been reported to impair flow mediated dilation (FMD) of the brachial artery. Endothelial dysfunction in coronary arteries can cause vasoconstriction during exercise. The aim of this study was to determine whether post-prandial endothelial dysfunction following a carbohydrate meal with or without added fat is associated with increased myocardial ischemia during exercise. Method: 20 subjects with CAD and a positive treadmill exercise test were studied. ln a randomised double blind cross-over design FMD of the brachial artery and ST segment depression during treadmill exercise were measured before and 3-4 hours after a high carbohydrate low fat milkshake (NoF) and an equivalent milkshake with 64g cooked fat added(F). Results: FMD of the brachial artery and ST segment depression during treadmill exercise were similar after the F and no F milkshakes. ST segment depression at equivalent sub-maximal exercise was greater after compared to before both milkshakes [before 1.02+0.70mm, after 1.26+0.76mm, p=O.O17] However FMD of the brachial artery increased after both meals [before 2.14%?1.29%, after 4.16%*3.06%, p=O.O33]. Conclusion: In this study brachial artery FMD was not impaired following the carbohydrate or added fat meal. Despite this myocardial ischemia during treadmill exercise was greater, suggesting mechanisms other than endothelial dysfunction cause post-prandial angina.

A POSITIVE CHANGE IN PATIENTS WELL BEING AND EARLIER RETURN TO WORK FOLLOWS AN EARLY PSYCHOLOGICAL INTERVENTION PROGRAMME POST-MYOCARDIAL INFARCTION. CJ Ellis*, KJ Petrie, LD Cameron, D Buick, J Weinman. Depts. of Medicine and Behavioural Science, University of Auckland, Auckland. Functional disability with lower levels of patient (pt) well being, despite being physically well, remains an important negative consequence of a myocardial infarction (MI). We assessed whether a hospital-based psychological intervention programme, designed to change inaccurate and negative illness perceptions of a MI, would result in less long-term disability and an earlier return to work. 65 first time MI pts (mean age x (SDy) years, 2% male) admitted to Auckland hospital coronary care unit, were randomly assigned into an intervention (n=x) or control (n=y) group. Both groups received the standard in-hospital cardiac rehabilitation programme. The 65 study pts completed a research questionnaire at baseline, immediately prior to hospital discharge (n=62) and at 3-month follow up (n=56). The X pts who received the psychological intervention programme underwent 3 separate hour-long interviews exploring pts initial understanding of a MI and its consequences, the level of possible future control of their illness with good secondary prevention, and an individualised ‘action plan’ for recovery We measured a variety of psychological scores, which demonstrated that the intervention programme resulted in significant positive changes in the pts view of their MI. (Expand here) In addition, pts in the intervention group reported being ‘better prepared’ for leaving hospital (p&05) and returned to work at a significantly faster rate than control pts (~~0.05). Conclusion: An in-hospital psychological intervention programme can positively change pts perceptions of a MI, resulting in an improved functional outcome and an earlier return to work.

Heart,

Lung

and Circulation

2001;

10

CONTROLLED TRIAL OF MULTI-CENTRE RANDOMISED ROACHING PATIENTS QN ACHIEVING CARDIOVASCULAR HEALTH (COACH); SECONDARY ENDPOINTS. M.J. Vale’. M.V. Jelinek. J.D. Best. A.M. Dart. L.E. Gigs, D.L. H re. B. Ho. R. Newman. J.J, w The COACH study group, Melbourne, Vittoria. Background: We have previously shown that coaching the patient with coronary heart disease (CHD) has a favourable effect on lipid outcomes. This study has assessed whether coaching could achieve beneficial outcomes for the other modifiable coronary risk factors. Methods: Patients with established CHD underwent a stratified randomisation by cardiac diagnosis in each of 6 teaching hospitals in Melbourne to receive either the coaching intervention (CI) or usual medical care (UC). The secondary endpoints measured at 6 months post-randomisation included: blood pressure, body weight, change in body weight from baseline to 6 months (Abody weight), fasting blood glucose. There were self-reported smoking status, alcohol intake and walking for exercise. Results: Risk Factor 1 Coaching Intervention 1 Usual Care ( P 1

(Kg) Fasting Glucose 6.10 (5.87 to 6.32) 6.24 (6.01 to 6.47) NS (mm&L) Smoking; n 38 (11.5%) 51 (14.7%) NS Walking (for 288 (87%) 258 (74%) 0.0001 exercise) I I Coachine resulted in a reduction in the number of alcoholic drinks per day (P
EFFECT OF MODERATE EXERCISE TRAINING CARDIAC REHABILITATION PROGRAMME ON HEART RATE VARIABILITY AITER ACUTE MYOCARDIAL INFARCTION. HW Cheun?. SY ID. LS Lui. YM Peon, LF Chan, WW Ghan. CC Lo. WC Wane. ML Ip. SY Wont WH Tsui. SY Hui. WH Fune. TE Sanderson, KS Woo. Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR. Background: Cardiac rehabilitation after acute coronary events has beneficial effect on quality of life and cardiovascular event recurrence. Heart rate variability (HRV) is an important prognostic marker for heart failure, cardiac dysrhythmias and sudden death. Exercise training may improve HRV by modifying autonomic activities. This study proposes to evaluate the effect of exercise training on HRV in patients after acute myocardial infarction (AMI). Methods: 21 AM1 patients without heart failure enrolled in the Phase II cardiac rehabilitation programme were studied. All subjects received a total of 1.5 hour health education in heart disease awareness and life style modification. 10 patients (mean age 59.5~8.4,9 males ) consented to receive a moderate intensity exercise training for 1 hour per week for 7 weeks, and were matched in age and gender with AM1 patients who had not joined the exercise programme (Control). HRV were assessed at baseline and after 7 weeks from 24 hour ambulatory electrocardiograms, using a Marquette analyzing system by a blinded investigator. Results: The 2 AM1 groups were also matched for their clinical characteristics at baseline and medications on discharge. No significant changes in their heart rate, body mass index and lipid profiles were seen in the 7-weeks period in both groups. There were slight increase in time domains HRV (SDNN, SDANN, I’NN50) (p>O.l), significant increase in HRV spectral power and decrease in low/high frequencies ratio in exercise group (*p < Baseline 7-week > SIJNN (ms) 73.7t17.7 x0.1+25.3 107.9+44.5 1X1+32.7 SDANN (ms) 58.0+25.0 61.5r22.7 75.3k28.3 95.5k33.9 I’NNJO (74) 3.9i2.8 5.7k7.2 9.Ok9.8 9.8k8.8 Total Power (ms2) 4.Od.93 5.6rl.O 6.2kO.7 7.3~060' Low Frequency (ms2) 3.6d.O 4.4kl.O 5.OkO.7 5.4*1 0 High Frequency (ms2) 2.9tl.O 3.3+0.9 4.0r1.2 5.1A.2 Low/High Ratio 1.3io.4 1.3+0.2 1.3r0.2 1.1+0.2* Conclusions: Moderate exercise training improves HRV, supporting the benefit of Phase II cardiac rehabilitation programme after AMI.

49th Annual

Scientific

Meeting

of CSANZ

A139

CAN LONG TERM VAD PATIENTS BE SUCCESSFULLY MANAGED IN THE COMMUNITY? CA. Wood’, H.M. Haves. R. Larbalestier. M. Best. M. Lovett, I.G. O’Driscoll. Cardiac Transplant Unit, Royal Perth Hospital, Perth, Western Australia. Background: The VAD program at the Royal Perth Hospital was established in January 1999 utilising the Thoratec TLC II device. The rapid expansion of the program resulted in the decision to upgrade and include the Heartmate VE LVAS into the bridging to transplant program as of August 2000. This paper outlines the challenges and experiences of an expanding outpatient based VAD program. It examines the complications associated with long term support in terms of clinical outcomes, mortality and morbidity, hospital readmissions, infections, embolic events, haemolysis and altered immunological status. Method: Thoratec TLC I1 - 4 males & 2 females, mean age 32 years. Aetiologies included ischaemic (1 patient), idiopathic dilated cardiomyopathy (4 patients) and fulminating myocarditis (1 patient). Heartmate VE LVAS - 3 males, average age 33 years. Aetiologies included idiopathic dilated cardiomyopathy (2 patients) and mitochondrial cardiomyopathy (lpatient). All patients attend an intensive competency based education program prior to discharge. 2 carers are nominated by each patient and undergo identical training. 24 hour on call nursing support is provided. The outpatient program includes weekly medical, nursing and technical assessment and 3 times weekly gym visits. Results: Thoratec TLC II Transplanted - 3 patients, 11,290 & 445 days post insertion. Death (within 24 hours of implantation) - 2 patients: 1 pulmonary embolus, 1 multiorgan failure. Actively listed - 1 patient, waiting time 240 days to date. Post Thoratec implant complications have included numerous driver failures, embolic CVA x 2, septicaemia, drive line infections, chronic haemolysis (resulting in multiple blood transfusions and VAD change), altered immunological status (PRA O-81%) resulting in IV intragam administration (1 patient). 3 patients have been managed in the community accounting for 27% of the total time supported. The Thoratec program at Rl’H only allows for one patient to be supported at home at any one time. In the event that there are 2 patients supported 1 must remain as an in patient on a rotational basis. Heartmate Actively listed - 3 patients, discharge post implant after 35 days, 45 days and 24 days. Total number of days supported 327 days. PRA status 0% in all patients. Post implant complication of 1 infected drive line requiring hospital admission. Conclusion: The experience of the WA Cardiac Transplant Unit and LVAD outpatients has been a positive one. Outpatient care is possible due to the portability of both devices and extensive patient training. The experience of the WA transplant unit has identified the Heartmate as a more reliable device with fewer complications to date.

IS 1T FEASIBLE TO SCREEN HEART FAILURE PATIENTS FOR SLEEP DISORDERED BREATHING IN A WARD SETTING? V.A. Booth*, C. McNallv, l? Batem& L. Conrv. I Wilcox. #ResMed Ltd, North Ryde, NSW, Cardiology Department, Royal Prince Alfred Hospital, NSW Congestive Cardiac Failure (CCF) is a major cause of hospitalisation. Sleep disordered breathing (SDB) occurs in - 50% of patients (pts) with CCF and treatment with Continuous Positive Airway Pressure (CPAP) can improve cardiac function and symptoms. Polysomnography is often impractical in this elderly, relatively sick, patient population. The aim of this study was to examine the feasibility of cardiac nurses performing a limited sleep-breathing diagnostic study on pts with CCF on a Cardiology ward. Methods and Results: Consecutive pts were screened overnight by ward nursing staff using an intelligent CPAP machine set in diagnostic mode (Autoset II P1usTM, ResMed Ltd). This method provided data on snoring, airflow limitation including apnwas, transcutaneous oxygen saturation, heart rate and respiratory movement. Results were classified by a blinded observer as: predominately obstructive, central or mixed sleep apnoea. Despite some technical difficulties, complete studies were obtained from 29 (73%) of the 40 pts screened. Two pts (2/40,5%) could not tolerate the device and incomplete data were obtained in 9 pts (23%) due to technical difficulties. Of 38 pts with partial or complete studies, 17 (45%) showed evidence of sleep disordered breathing [lo obstructive (26%), 4 central (11%) and 3 mixed (8%)]. Conclusion: This study demonstrates that it is feasible to screen pts with CCF for sleep apnoea on a cardiac ward using relatively simple, non-invasive technology. Sleep apnoea was common (45% of p’s) but in contrast to previous studies most had obstructive (OSA) rather than central or mixed apnoeas. While this preponderance of OSA may be explained by the technical limitations of this device in detecting of central apnoeas, it is possible that OSA is more common in this population than previously known.

A140

49th Annual

Scientific

Meeting

of CSANZ

Heart,

THE TRUE IMPACT OF HEART FAILURE ON SURVIVAL USING ANALYSIS OF REMAINING LIFE YEARS. RN Douehtv’. GD Gamble SF Wrieht. N Sharoe. Dept of Medicine, University of Auckland. Background: Heart failure (HF) has a significant effect on and projected lifespan of both yotmg and old patients. Patients with a first admission with heart failure in New Zealand have a 1 year mortality of 30% and a 5 year mortality of 60%. Conventional survival curve analysis utilises time from disease onset to death; this neglects the patient’s expected life span if they had no heart failure. This study utilises a new method of examining prognosis, the real life expectancy method (RLEM) which takes account of age at diagnosis on survival. This analysis, which calculates fraction of normal remaining lifeyears (%NRL), can determine the true effect of a diagnosis of heart failure on expected survival. Methods: National statistics for all-cause mortality in patients with a first admission with HF with were obtained from the New Zealand (NZ) Health Information Service using ICD-9 codes for HF both as a 10 diagnosis or a 20 diagnosis. Normal life expectancy for NZ adults of different ages were obtained from Statistics NZ 1995-1997 data. Each patient with HF could be identified by a unique encrypted number. Normal remaining life-years (NRL) were calculated by subtracting normal life expectancy at age of first HF admission from the normal life expectancy at that age. The time from first HF admission to death was then calculated and divided by the NRL to obtain the % of NRL that had been lived by the patient. This allows the survival time to be plotted on survival curves as % of remaining life which would have been lived if the patient did not have HF, rather than being plotted as years lived from diagnosis. Results: See table. Whatever a patients’ age at first hospital admission, the impact of HF on % estimated remaining lifespan was similar (25 to 37%). Overall half of patients with a first HF admission can expect to survive only 28% of their expected natural lifespan. Age group 55-65 66-75 76-85 x35

Normal average life expectancy (yrs,: NRL 22 15 10 5

Remaining life-years with diagnosis of HF (yrs) 6.4 3.9 2.5 1.5

Impact of HF, in % NRL -37% -25% -25% -30%

Lung

and Circulation

THE CURRENT COST OF HEART FAILURE HEALTH SERVICE IN THE UNITED KINGDOM. and 1.1. McMurrav. CRl in Heart Failure, University ment of Economics, City University, London, United

2001; 10

TO THE NATIONAL S. Stewart*. A. McGuire of Glasgow and DepartKingdom.

Background: We have recently shown that heart failure (HF) admission rates continue to increase in the UK - particularly in older age groups. As hospital activity represents the major cost component of health care expenditure related to HF, this study evaluated the current cost of this syndrome to the National Health Service (NHS) in the UK. Methods: We applied contemporary estimates of health care activity associated with HF to the whole UK population on an age and sex-specific basis to calculate its cost to the NHS for the year 1995. Direct components of health care included in these estimates were hospital admissions associated with a principal diagnosis of HF, associated outpatient consultations, General Practice consultations and prescribed drug therapy We also calculated the cost of nursing home care following a primary HF admission and the cost of hospitalisations associated with a secondary diagnosis of HF. Adjusting for probable increases in hospital activity and costs, in addition to the progressive ageing of the UK population, we have also projected the cost of HF to the NHS for the year 2000. Results: We estimated that there were 988,000 individuals requiring treatment for HF in the UK during 1995. The “direct” cost of health care for these patients was estimated to be E716 million or 1.83% of total NHS expenditure. Hospitalisations and drug prescriptions accounted for 69% and 18% of this expenditure, respectively. The additional costs associated with long-term nursing home care and secondary HF admissions following primary HF admissions accounted for a further E751 (2.0% of total NHS expenditure). By the year 2000 we estimated that the combined total cost of HF had risen to E905.3 million -equivalent to 1.91% of total NHS expenditure. Conclusions: These findings re-confirm, using well validated sets of data, the importance of HF as a major public health problem in the UK. The annual direct cost of HF to the NHS in 2000 is likely to be in the order of 1.9% of total expenditure-the predominant cost component being hospitalisation.

Conclusions: The diagnosis of HF has a profound effect on %NRL years regardless of age at diagnosis. The RLEM technique of survival analysis allows prognosis in HF to be clearly and simply expressed, and has potential uses in terms of advising patients and deciding on treatment in individuals, and surveillance of survival trends in populations. NATURAL HISTORY OF FUNCTIONAL MITRAL REGURGITATION IN DILATED CARDIOMYOPATHY. E Kotlvar*. AM Keozzh, PS M cdonald, M. Fenelev. S D’AIcv. D.McCaffrev. Heart & Lung Transpkt Unit, St Vincent’s Hospital, Darlinghurst, NSW. Background: Functional mitral regurgitation (fMR) due to annulus dilatation in dilated cardiomyopathy contributes to heart failure and is associated with worse prognosis. Carvedilol reduces left ventricular (LV) dimensions and improves function. This study evaluates the effect of carvedilol on degree of fMR. Study Population: 471 patients (407 men and 65 women) aged 55+13years (range 10-91) with symptomatic heart failure due to dilated cardiomyopathy on maximal medical therapy commenced carvedilol between February 1996 and December 2000. Aetiology was idiopathic dilated cardiomyopathy in 246, ischaemic cardiomyopathy in 187 and other in 38 patients. Methods: The patients were followed at 3, 6, 12, 18, 24, 36 and 48 monthly cliic visits where their New York Heart Association (NYHA) functional class, tolerability and adverse side effects were assessed. Echocardiography was performed at each visit, measuring LV dimensions and de ee of MR. The degree of MR was determined by semi-quantitative metho r s and graded as zero (0), trivial (l), mild (2), mild-moderate (3), moderate (4), moderate-severe (5), and severe (6). Results: Mean follow up was 39illmonths (range 6-59). Data were excluded in 4% who underwent mitral valve surgery, 9% cardiac transplantation, 3% bypass surgery, 3% other cardiac procedure, leaving 380/471 (81%) in whom natural history could be observed. 331/380 (87%) tolerated carvedilol for 2 12 months. To date 12 month data are available in 224/380 (59%). n NYHA class LVEDD (mm) LVESD (mm) FS (%) Degree of MR Data expressed as Mean k sd,

Baseline 224 2.9kO.8 72+11 62k12 0.16t0.09 2.0r1.5

12 months

p value*

224 2.2+0.8 71+12 58r14 O.mtO.08 1.6~1.5


‘paired hvo tailed t test analysis

At 12 months, 42% of patients on carvedilol had less fMR, 23% had more fMR and 35% had no change in the degree of fMR. Conclusion: Carvedilol improves functional class, decreases LV end-systolic dimension and reduces the degree of fMR in significant number Of patients.

EXERCISE LIMITATION IN CHRONIC HEART FAILURE IS CAUSED BY STRUCTURAL CHANGES IN SKELETAL MUSCLE NOT REDUCED OXIDATIVE CAPACITY. A.D. Williams*, ME Carev. S. Selig, H. Krum. A. Haves. D.G. Menzies. I. Patterson, R.H. Geerline. N. Butler, V. Bamroonesuk. D. Toia and D.L. Hare. Centre for Rehabilitation in Exercise and Sport Science, Victoria University of Technology, Department of Cardiology, Austin & Repatriation Medical Centre. Chronic heart failure (CHF) patients have profound exercise intolerance due to maladaptations in the skeletal muscle rather than reduced cardiac function. The aim of this study was to compare a range of metabolic and structural variables in skeletal muscle of CHF patients and healthy age matched controls. Methods: Resting muscle biopsies were taken from the vastus lateralis of twelve patients with stable CHF, NYHA II & III; age 68 f 9 years; LVEF = 27 f 8% (mean & SD) and eight healthy sedentary subjects, age = 63 & 11 years. Muscle samples were analysed for mitochondrial ATP production rate (MAPR), oxidative and glycolytic enzyme activity, fibre type proportions and sizes, and capillary density. Total body 0, uptake (VO, e.k) was determined using symptom - limited, graded cycle ergometry. Res t&s: VO+* is significantly lower in CHF versus normal subjects (15.1 vs. 28.1 ml/kg/min; p = 0.0004). There are no differences between CHF patients and healthy controls in skeletal muscle oxidative metabolism as determined by MAPR using a range of substrates (lowest p = 0.51), or oxidative enzymes citrate synthase (p = 0.71) or 3 - hydroxyacyl coenzyme A dehydrogenase (p = 0.33). CHF patients have a lower capillary to fibre ratio (1.09 vs. 1.40; p = 0.0008) particularly around type I fibres (3.05 vs. 3.82; p = 0.005). Although there is a tendency for type I fibres (oxidative) to be smaller in CHF (3096 vs. 3681 lm*; p = 0.0698), the proportions of this fibre type are not different from healthy subjects. CHF patients also have significantly smaller type IIA (oxidative and glycolytic) (20.6 vs. 35.3%; p = 0.0003) and larger type IIB (glycolytic) fibre proportions (31.0 vs. 18.5%; p = 0.0002). Conclusion: Compared with normal controls, skeletal muscle in CHF patients has normal oxidative capacity but lower type IIA and higher type IIB fibre proportions, reduced capillary density and type I fibre atrophy. We conclude that these structural adaptations are responsible for the reduced exercise tolerance in CHF.

Heart,

Lung and Circulation

49th Annual Scientific Meeting of CSANZ

2001; 10

AN ABBREVIATED TWO-CATHETER TECHNIQUE FOR CATHETER ABLATION OF SUSPECTED ATRIOVENTRICULAR NODAL REENTRANT TACHYCARDIA. M.A. Barlow*. John Hunter Hospital, Newcastle; A.C. Skanes, C.S. Simoson, F. Mureatrovd. A.D. Krahn. R. Yee. G.1. Klein. University of Western Ontario, London. Objective: This prospective randomized study assessed the feasibility of an abbreviated technique (ABT) for catheter ablation in patients with suspected atrioventricular nodal reentrant tachycardia (AVNRT). Methods: Thirty consecutive patients (pts) with a pm-study 12lead ECG suggestive of AVNRT were randomized to either ABT or standard technique (STT). The ABT employed only 2 catheters, the STT 4 catheters. The major criterion used for confirmation of the diagnosis of AVNRT was the reproducible induction of echoes or tachycardia showing a VA interval of -25 to 60 ms at the His. Failure to achieve this resulted in crossover to the SIT. Results: The mean age was 51 years (24-77) (87%) were female. Patient number Cath. placement (min) Diagnostic Study (min) Ablation (min) Total Procedure (min) Fluoroscopy time (min)

ABT 13 11 *4 22 *9 22 +12 86 A 17 9 A.5

STI 14 23 34 27 114 12

P Value 28 *17 ?I2 *8 +5

O.OOOl 0.03 0.32 0.0003 0.14

Crossover from ABT to SIT was necessary in 3 pts (not included in the analysis). After crossover 2 had typical AVNRT confirmed, 1 had atrioventricular reentrant tachycardia (AVRT). Total procedure duration averaged 146 + 28 min. Two pts randomized to SIT had AVRT diagnosed. All remaining pts fulfilled criteria for proceeding with slow pathway ablation. This was complicated by transient AV block (not requiring intervention) in 4 pts (2 in ABT group, 2 in STT group). No other complications occurred. All procedures were successful and only one recurrence has occurred to date (follow-up, >26 weeks). Conclusions: ABT appears equally safe and effective as SIT for ablation in pts with suspected AVNRT. It offers the potential to significantly reduce procedural time without compromising diagnostic accuracy.

EVALUATION OF THE ROLE OF 24 HOUR HOLTER MONITORING IN IDENTIFYING PATIENTS WITH INDUCIBLE VENTRICULAR TACHYCARDIA AFTER MYOCARDIAL INFARCTION. A. Thiaealineam*, V. EiDDer. C. Camobell. D.L. Ross, T.B. Uther P. Kovoor. Department of Cardiology, Westmead Hospital, NSW Implantable cardioverter/defibrillators (ICDs) have been shown to reduce mortality in patients with inducible ventricular tachycardia (VT) post myocardial infarction (MI) in the presence of both left ventricular impairment and non-sustained ventricular tachycardia on Holter monitoring. Patients with inducible VT alone however are at high risk for sudden cardiac death. We followed a protocol of performing Holter monitoring and electrophysiological studies (EPS) in all patients with an ejection fraction (EF) ~40% post MI. Consecutive patients ~75 yrs of age (n=489) presenting with an acute myocardial infarction to hospitals in the Western Sydney Area Health Service were screened. A gated heart pool scan was performed on 375 patients (77%) and 85 patients had an EF ~40%. Holter monitoring of 50 of these patients showed runs of VT (3-30 beats) in 16 (32%). An electrophysiological study using up to 4 extrastimuli was performed on 61 patients. Sustained (>lO s) VT with a cycle length Z230 ms was inducible in 14 (23%) of the 61 patients using E3 extrastimuli. The VT had a mean cycle length of 274 ms (230-360 ms) and required a mean of 2.6 extrastimuli for induction. Ventricular flutter/fibrillation was inducible in 40 (65%) patients using up to four extrastimuli. The median follow up was 114 days. The results of Holter monitoring was crosstabulated with the EPS result to show: EPS +ve Holter +ve 4 patients, no events EPS +ve Holter -ve 9 patients, 1 cardiac death

EPS -ve Holter +ve 11 patients, 1 cardiac death EPS -ve Holter -ve 23 patients, 1 non cardiac death

ICDs have been implanted in 12 of the 14 patients with inducible VT (one patient died from VT in hospital while awaiting ICD implantation and another had surgical excision of the left ventricular aneurysm). In conclusion, Holter monitoring fails to identify many patients with inducible ventricular tachycardia post MI.

A141

EARLY EXPERIENCES WITH BIVENTRICULAR PACING FOR THE TREATMENT OF ADVANCED HEART FAILURE. HR Weerasooriva, MIE Department of Cardiology, Royal Perth Hospital, Perth, Western Australia and Hollywood Private Hospital, Nedlands, Western Australia. Introduction: We describe our early experiences with biventricular (BiV) pacing, a new treatment option for patients with advanced heart failure and a wide left bundle branch block (LBBB). Methods: BiV pacing was attempted in 13 pts (10 male) aged 65rll yrs with a LBBB and mean QRS width of 178+24 (mean f sd.) msec. All pts had a left ventricular ejection fraction < 35%. Causes of cardiomyopathy were; ischaemia (8 pts), idiopathic (4 pts) and valvular disease (1 pt). Concomitant problems included: complete heart block (1 pt), chronic atria1 fibrillation (2 pts), ventricular arrhythmias requiring implantable cardioverter defibrillator (ICD)(L pts), previous atrioventricular junction ablation with insertion of WIR pacemaker (1 pt). The following pacing systems were used: InSyncTM (Medtronic, Inc., Minneapolis, MN) with a precurved coronary sinus (CS) pacing lead (2 pts), Contak TRTM (Guidant Corp., St Paul, MN) with an over-the-wire CS lead (9 pts), and Contak CDTM [ICD + BiV pacemaker] (Guidant Corp., St Paul, MN) with an over-the-wire CS lead (2 pts). The CS ostium was localised using the following techniques; prior coronary angiogram showing late filling of the CS, limited coronary angiogram during procedure, probing with a guide wire and contrast injection via the CS guiding sheath. The LV lead was placed in a lateral, posterolateral or anterior coronary vein. Results: The mean procedure time was 159 (range 50-255) min and mean fluoroscopy time was 49 (range 15-92) min. BiV pacing was not achieved in 3 pts because of failure to cannulate the CS (1 pt) and because of high pacing thresholds in the LV veins in 2 pts with ischaemic cardiomyopathy. The 10 pts with BiV pacing were followed at 2 1 mo with the following results. The mean NYHA class improved from 3.2r0.4 pre to 2.0-r0.8 post BiV pacing. The mean QRS width shortened from 17&24 msec pre to 154r31 msec post BiV pacing. BiV pacing was discontinued in 1 pt because of ventricular bigeminy. One pt experienced diaphragmatic pacing requiring reduction of the LV lead output without loss of LV capture. Conclusion: Early results indicate that BiV pacing can be achieved using a variety of techniques and pacing systems in the majority of pts with advanced heart failure and a wide LBBB. BiV nacine oroduced clinical improvement in the majority of these highly selected pts.” ’

RADIOFREQUENCY ABLATION OF ACCESSORY THE FONTAN OPERATION. J.R.S kYmer*., Auckland.

PATHWAYS AFTER Green Lane,

After the Fontan operation, reduced access to the heart and complex congenital heart disease creates unique difficulties in radiofrequency ablation (RFA). We present two such children with poorly tolerated adenosine responsive SVT and with intermittent delta waves. 1. 12 year old boy with atriopulmonary connection for tricuspid and pulmonary atresia. Delta wave suggested a left-sided pathway, but retrograde mapping of the mitral valve annulus was unrewarding. Mapping in the right AV groove initially revealed uninteresting signals until the catheter was placed into the anterior portion of a very small blind-ending pocket in the centre of the tricuspid valve area. The accessory pathway (Al’) was successfully ablated with RF3. Flour0 time (ET) 19mins, procedure time (Pl) 8lmins. No recurrence 3 for months. 2. 12 year old girl with total cavopulmonary connection for common AV canal, double inlet and outlet right ventricle, LTGA and dextrocardia. Atria1 signals (only) from the conduit. Retrograde inlet valve mapping showed an anterior and rightward His bundle, and Al’ posterior and leftward, and was ablated with RF 2. Decremental VA conduction thereafter. (FT llmins, PT 12Omins.) Recurrence of SVT 2 months later, repeat EPS with 2 retrograde catheters in RV revealed a second, concealed anterior and leftward AP; the decrement&y was in fact due to delayed intratrial conduction. RF 8 was successful. VA block after this. (ST 27mins, PT 185mins). No recurrence for 22 months. Conclusions: Right sided accessory pathways, ablatable with RF energy, can occur in tricuspid and pulmonary atresia. Ablation of accessory pathways is challenging but feasible post Fontan using a reduced number of catheters.

Al42

49th Annual

Scientific

Meeting

of CSANZ

Heart,

A RETROSPECTIVE CASE STIJDY TO ASSESS THE VALUE OF AN IMPLANTABLE LOOP RECORDER FOR THE INVESTIGATION OF UNDIAGNOSED SYNCOPE. D.T. Ashbv*, D.A. Cehic. P.J.S. Disney. L.J. Mahar and G.D. Young. Royal Adelaide Hospital and Adelaide Cardiology, South Australia. If not diagnosed by history, examination or ECG, the diagnosis of syncope can be difftcult with a low yield from echocardiography, ambulatory ECG recording, EP study and tilt-table testing. Over two years, fifty patients with unexplained syncope or presyncope from three hospitals underwent the implantation of a Medtronic Reveal implantable loop recorder (ILR) capable of cardiac monitoring for 18 months. All patients had at least two prior episodes of syncope or presyncope. Fifty percent of patients had EP studies, all of which were negative. The ILR remained implanted until a diagnostic event was recorded, or until the end of the battery life. After a mean follow-up of 6.2 f 5.6 months, symptoms reoccurred in 26 patients (52%) at a mean of 2.8 f 2.2 months after ILR insertion. No further symptoms occurred in 24 patients (48%). In seven patients the follow-up has been six months or less. Of the twenty-six patients who had a symptom and recorded an event, an arrhythmia was seen in 10 patients (38%). Of these, seven patients had bradycardias; two having bradycardia associated with the cardioinhibitory component of neurally mediated syncope and five had bradycardias associated with conducting system disease (four with sick sinus syndrome and one with complete heart block). Three patients had taohycardias; two with supraventricular taohycardia and one with atria1 flutter. Sixteen of the twenty-six patients (62%) who activated their device due to syocope or presyucope were in sinus rhythm during the event. These were diagnosed as having a noncardiological cause for their symptoms.

In conclusion, non-cardiological patients.

the ILR was effective in making a cardiological or diagnosis for unexplained syncope in 52% of our

The remaining

subjects

have had no further

syncopal

events.

EFFICACY OF AN IMPLANTABLE LOOP RECORDER IN THE DIAGNOSIS OF SYNCOPE. W.M. Smith*, M.A. Hood, J. Stewart. F. Riddell. From the Cardiology Unit, Green Lane Hospital, Auckland, New Zealand. Validating the mechanism of syncope is often difficult. We implanted a loop recorder (Medtronic Reveal and Reveal plus) in 16 patients in whom preliminary tests for syncope were inconclusive. Such investigations included rest and exercise ECG (abnormal in 5/16 and l/7 respectively), tilt table testing abnormal in 4/14, negative neurological consult in 12 and EPS abnormal in 4/7. With increasing experience there was a tendency to early implantation with limited testing. The MF ratio was 79, mean age 42 (range 12-73 years) with 5 having structural heart disease (coronary artery disease 2, cardiomyopathy 3). Syncope occurred once in 2 patients, 2-4 times in 9 and >5 in 5 causing serious injury in 4 and a motor vehicle accident in 2 patients. Ten devices were patient activated only and 6 both patient and auto-activated. Recording artifact/problems occurred in 6 patients, mainly with autoactivations. A record of the cardiac rhythm during typical symptoms, allowing definitive management, was achieved in 6 patients, (VT and AV block one pt each, sinus rhythm 4 pts). Two devices were implanted without activation and no activation has occurred in 8 patients after 1-16 months exposure. Diagnosis was thus achieved in 70% of patients with an event or at least 6 months recording. We conclude: 1. Recourse to an implantable recorder has an acceptable probability of confirming/excluding a cardiac arrhythmic cause of syncope. 2. Artifact is a problem with second generation auto-activated devices. 3. Early implantation without additional testing seems warranted in selected patients.

Lung

and Circulation

2001; 10

HEPARIN-INDUCED THROMBOCYTOPENIA TYPE II IS A COMMON COMPLICATION SEEN IN CARDIAC TRANSPLANT RECIPIENTS. L A Houriear?. D L. Walters. G W Dec. Cardiac Transplantation Unit, Massachusetts General Hospital, Boston, U.S.A. Background: Heparin-induced thrombocytopenia type II (HIT II) is a serious immune-mediated complication of heparin therapy that occurs in approximately 2-3% of the general population of patients who receive at least five days of unfractionated heparin. Paradoxically, this condition confers a high risk for both arterial and venous thromboembolic events via platelet and endothelial activation by anti-heparin/ platelet factor 4 (H-PF4) immune complexes. It may occur in as many as 35% of surgical patients and carries a 20-27% mortality. Treatment involves cessation of the drug or any drugcoated catheters and anticoagulation with another agent such as the thrombin inhibitor argatroban if thrombosis develops. Cardiac transplant candidates are frequently exposed to heparin through i&a-venous lines, prolonged use of intraaortic balloon pump support and increasingly, ventricular assist device implantation prior to transplantation. Given the associated potential risk and the need for ongoing repeat exposures to heparin flushes at the time of right ventricular biopsies and routine coronary angiography, we sought to determine the incidence of HIT II in cardiac transplant recipients. Methods: We retrospectively reviewed the incidence of HIT II in all cardiac graft recipients transplanted at our institution between January 1998 and December 2000. HIT II positivity was determined by enzyme-linked immunosorbent assay (ELISA) for the antibody to the H-PF4 complex. Results: 46 patients (5 women; 41 men) aged between 17 and 67 years (mean 54) were transplanted during this time period. An ELISA for the antibody to the H-PF4 complex was performed, at some stage, in 22/44 (50%) patients. lo/44 (23%) had at least 1 positive test and 2/44 (5%) had “borderline” results. Overall mortality for patients transplanted during this time was 14% (6/44); including 1 of the 10 HIT-positive patients and 1 of the 2 “borderline” HIT-positive patients. Conclusions: HIT-II occurs more commonly in cardiac transplant patients compared with the general population receiving unfractionated heparm. It is possible that the proportion of these patients affected was underestimated given that the antibody was assayed in only half of the cohort. The increased incidence in this group likely reflects their recurrent and often prolonged exposures to the drug. In general, screening of asymptomatic patients for the H-PF4 antibody is not recommended as the percentage of those who develop the antibody is higher than the percentage who go on to develop clinical sequelae. Our findings suggest that prospective screening in the cardiac transplant population be considered given their recurrent exposures to heparin during follow-up procedures.

TIRILIZAD (U74389Gl SUPPLEMENTED CARDIOPLEGIA DOES NOT PROVIDE ADEQUATE PROTECTION FOR PORCINE CARDIAC ALLOGRAFTS SUBJECTED TO 12 HOURS OF HYPOTHERMIC ISCHAEMIC STORAGE. J Rvan’, M Wilson, M Hicks, S Kesteven. S Garlick. A McCall. M Fenelev & P Macdonald. Heart & Lung Transplant Unit, St. Vincent’s Hospital, Sydney, Australia. Background: We have previously reported that the addition of Tirilizad, a 21-aminosteroid, to standard cardioplegia reduces cardiac allograft injury following 6 hours of hypothermic ischaemic storage. Aim: To determine if ‘Ilrilizad supplemented cardioplegia provides sufficient protection to allow successful transplantation following 12 hours of hypothermic ischaemic storage. Methods: Brain death was induced in the donor pig by inflation of a subdural balloon. One hour later, the donor heart was arrested with 900ml of conventional crystalloid cardioplegia which had been supplemented with 0.03mmol of Tlrilizad and its carrier solution (1OOml of 10% Intralipid & lOmmo1 HCI). The heart was harvested immediately then placed in ice before being transplanted orthotopically into the recipient pig with a total ischaemic time of 12 hours. The hearts were supported with ventricular demand pacing and dobutamine at lOmcg/kg/min. Attempts were made to wean cardiopulmonary bypass at 1, 2 & 3 hours post reperfusion. Dobutamine was weaned over 1 hour, commencing 5 hours post reperfusion. Results: Six transplants were performed. Only 3 hearts could be weaned from cardiopulmonary bypass (one each at 1, 2 & 3 hours post reperfusion). All 3 suffered recurrent ventricular tachycardia and / or fibrillation. Two failed before the dobutamine was reduced while the third failed following dobutamine withdrawal. Conclusion: Tirilizad supplemented cardioplegia does not provide sufficient protection to allow reliable transplantation of porcine cardiac allografts subjected to 12 hours of hypothermic ischaemic storage.

Heart,

Lung

and Circulation

49th Annual

2001; 10

AN EVALUATION OF THE PRELOAD INDEPENDENCE OF THE NEW ECHOCARDIOGRAPHIC INDICES OF DIASTOLIC FUNCTION IN PATIENTS UNDERGOING HAEMODIALYSIS. -Graham. p. Mottram, IS. Gelman. R.E. Peverill’ Centre for Heart and Chest Research, Department of Medicine, Monash University and Monash Medical Centre, Clayton, Victoria Assessment of mitral annular motion diastolic velocities by M-mode or tissue Doppler imaging (TDI) and the propagation velocity of early diastolic filling by colour M-mode have been proposed as preload-independent indices of diastolic function. The aim of this study, performed in patients with chronic renal failure and volume overload, was to determine the effects of preload reduction by haemodialysis on these new echocardiographic indices and compared them with standard mitral inflow variables. The study group comprised 16 patients in sinus rhythm, of mean age 57 years (range 29-75 years), without significant valvular or pericardial disease and without regional wall motion abnormalities. Subjects underwent echocardiography 30 minutes prior to and 30 minutes following haemodialysis. Following dialysis there were significant reductions in weight (68.9+18.0 to 67.3k17.6 kg, pO.25 for all). There was a trend to a decrease in colour M-mode propagation velocity after dialysis (61 to 56 cm/set, p=O.O9). In conclusion, our findings suggest that TDI of mitral annular motion provide an echocardiographic measurement of diastolic function which is independent of preload, but raise the possibility that M-mode early diastolic annular velocity and colour M-mode propagation velocity may not be preload independent.

FEASIBILITY OF TRANSOESOPHAGEAL TISSUE DOPPLER VELOCITY, STRAIN AND STRAIN RATE IMAGING IN THE OPERATING THEATRE. L.A. Simmons*. F. Weidemann. l? Wouters. 1. D’hooee. B. Biinens. G.R. Departments of Cardiology and Anaesthesia, UZ Gasthuisberg, Leuven, Belgium. Aim: Transoesophageal echocardiography is increasingly used to monitor myocardial function during cardiac surgery. Doppler myocardial imaging provides information about regional myocardial motion (velocity and displacement) and deformation (strain and strain rate). This study examined the feasibility of transoesophageal acquisition of velocity, displacement, strain and strain rate data during cardiac surgery and evaluated the effects of sternotomy and pericardial opening on these indices. Methods: Following a baseline transthoracic echocardiographic study, transoesophageal echocardiography was performed in 22 patients (age 64+7 years, 16 men) prior to sternotomy, after sternotomy with intact pericardium and after pericardial opening. Regional velocity analysis was performed for the transgastric anterior and inferior walls of the left ventricle (radial function) and the 4-chamber septum and left ventricular inferior wall (longitudinal function). For each segment, systolic and diastolic velocities were calculated and displacement, natural strain and strain rate data were derived. Results: Transthoracic and transoesophageal imaging provided similar data from an equivalent number of interpretable segments. In the basal and mid septum, maximum longitudinal systolic displacement was decreased with pericardial opening (basal septum closed pericardium 6.6*1.5mm, open pericardium 4.6&1.8mm, p=O.O07; mid septum closed pericardium 4.7+2.5mm, open pericardium 2.7+1.5mm, p=O.O28). No further changes were evident in systolic or diastolic velocities, displacement, strain or strain rate in other segments.

Conclusions: Transoesophageal Doppler myocardial imaging is feasible during cardiac surgery and provides information about both radial and longitudinal left ventricular function. Doppler myocardial indices require further evaluation in the detection of ischaemia in the operating theatre.

Scientific

Meeting

of CSANZ

A143

EVALUATION OF MYOCARDIAL DOPPLER VELOCITY, STRAIN AND STRAIN RATE IN IDIOPATHIC DILATED CARDIOMYOPATHY. F. Weidemann. C. Dommke. L.A. Si m mon s * , L I-I erb ots, M. Kowalski. of CarJ. D’hoo ee. l’. Claus, B. Biinens. L. Hatle. G.R. Sutherland. Department diology, UZ Gasthuisberg, Leuven, Belgium. Aim: The study sought to characterise regional myocardial motion and deformation in the left ventricle (LV) of patients with idiopathic dilated cardiomyopathy (DCM) using Doppler myocardial imaging (DMI). Methods: Colour DMI regional data were obtained at high frame rate (150 frames/s) in 13 patients with DCM (age 44+16 years, 9 men, LV ejection fraction 2427%) from the parastemal short axis (SAX) posterior wall basal segment (radial function) and the 4-chamber septum and 3-chamber (3C) posterior wall basal, mid and apical segments (longitudinal function). Data was post-processed to determine maximal systolic velocity (V), strain (e) and strain rate (SR). Results: Radial and longitudinal LV function (V, E and SR) were uniformly reduced in all walls and segments in DCM compared with reference values from our laboratory for normal adults. In DCM, a base to apex gradient similar to that observed in normal adults was evident in septum and posterior walls for V but not S or SR. Systolic deformation was increased in the radial (SAX posterior wall basal segment) compared with the longitudinal (3C posterior wall basal segment) direction (e and SR p
SAX Basal Posterior 3C Basal Posterior 3C Mid Posterior 3C Apical Posterior

Velocity km/s) 2h1.4 3.4il 9 2.621.9

Strain (%) 26517

2.lk1.8

Rtll

14+6 13*11

Strain Rate (s-‘) 2.1t1.0 0.9kO.6 0.8iO.3 0.7io.4

Conclusions: Radial and segmental longitudinal systolic deformation of the LV are uniformly reduced in DCM. Doppler myocardial indices may prove useful in characterising ventricular function in patients with both global and regional systolic dysfunction of the LV.

LEFT VENTRICULAR MASS IS NOT DETERMINED BY ADIPOSITY TYPE 2 DIABETICS. G.A. Wha llev’. G.D. Gamble. W. Baee, R.N. Douehtv, H.1. Department of Medicine, University Auckland, New Zealand.

IN of

Diabetics have worse cardiovascular prognosis than non-diabetics, part of which has been attributed to excess LV hypertrophy (LVH). Left ventricular mass (LVM) is often estimated using echo to assess LVH. LVM is related to body size, and is usually indexed to body surface area (BSA) to compare individuals and groups of differing body habitus. However, it has been shown that LVM is most closely associated with fat free mass (FFM) in children and adults and FFM may be a better indexing variable. Aim: This study aimed to investigate the relationships between LVM and body composition in order to identify the best determinant(s) of LVM in type 2 diabetes mellitus (DM) and to differentiate between hypertensive DM and normotensive DM. Methods: Echo and dual energy x-ray absorptiometry (DEXA) were performed in 140 subjects, who were divided into four groups: hypertensive diabetics (HTN-DM, n=22), normotensive diabetics (DM, n=25), hypertensive non-diabetic controls (HTN, n=46), normotensive non-diabetic controls (N, n=50). Univariate correlations and stepwise multiple linear regression were determined between LVM and height, height 1.5, height 2.7, weight, BSA, body mass index (BMI), waist-hip ratio (WHR), fat free mass (FFM), bone mineral content (BMC) and fat mass. Results: In all four groups, FFM was the best independent and significant determinant of LVM (HTN-DM: R2=0.32; DM: R2=0.50; HTN: R2=0.29; N: R2=0.35). Weaker predictors included age (N: RZ=0.06; HTN: RZ=0.06), WHR (DM: RZ=0.05; N: R*=0.04) BMI (HTN: R2=0.08) and BSA (DM: R’=O.12). In multivariate analysis, FFM was the most important predictor of LVM, in all groups. Neither fat mass, nor height were independent predictors of LVM, and although both BSA and WHR were significant predictors of LVM, their contribution was smaller. Conclusions: Fat mass is not a determinant of LV mass in this diabetic population. LV mass is determined by fat free mass in diabetes and supports the use of fat free mass as the most appropriate indexing variable for LV mass. This is particularly important, given the higher proportion of obesity associated with diabetes.

A144

49th

Annual

Scientific

Meeting

of CSANZ

Heart,

UTILITY OF NEW DIASTOLIC FUNCTION INDICES TO PREDICT STRUCTURAL CARDIAC ABNORMALITIES IN PATIENTS WITH CARDIOMYOPATHY. JJ Per&a*. DL Prior, AM Foe&v, NG Mahon. M Martin, Ml Garcia. RC Starline. ID Thomas. AL Klein. The Cleveland Clinic Foundation, Cleveland, Ohio, USA and St Vincents Hospital, Melbourne, Australia. Objective: Combined Doppler indices that include pulsed Doppler early mitral inflow velocity (E) and tissue Doppler (E/E‘), or color M-mode Doppler (E/VP) as well as E wave deceleration time (DT) provide an estimate of left ventricular (LV) filling pressures. We sought to determine whether these indices are associated with specific diastolic function abnormalities including increased left atria1 area (LAA), advanced right ventricular dysfunction (RVD) and elevated pulmonary artery systolic pressure (PAP). Methods: We prospectively studied 43 patients in sinus rhythm with heart failure secondary to ischemic or dilated cardiomyopathy (CM) and LV ejection fraction < 35%. Comprehensive echocardiography examination including assessment of lateral (Lat) mitral annular velocities (s‘, E‘, A‘) and mitral inflow velocitv of propaaation (Vu) was performed in allots. Results: ElVp LAA 5 20 cm2 LAA > 20 cm2 No RVD RVD

WLatE

L&B/A 2.5kO.6 §3.0+0.9

0.9kO.3 ~1.2*0.7

2.7eO.8 3.kO.9 2.7k0.8

0.9kO.3 11.5+0.9 l.OkO.3

7.3+4.9 10.2t4.2 8.7t4.4 10.3k4.9 9.7+5.1

n&o.9

11.1*4.3

PAP < 4OmmHg PAP > 4OmmHg 3.3rkO.8 +r=o.o1, *P=0.02,5P=o.o4 P=O.O5

DT(msec) 233+85 1173+71 216+79 +153?66 192+74 n33*36

By conventional criteria there were 20 pts in the impaired relaxation group (gp), 9 pts in the pseudonormal gp, and 14 pts in the restriction gp. A cut-off for E/VP of > 2.9 and E/E‘ of > 10.0 was 89%/80% sensitive and 84%/81% specific in correlating patients with the restriction gp. Conclusion: 1) New modalities for the diagnosis of diastolic dysfunction, in combination with mitral inflow parameters, help stratify patients with CM. 2) The differences correspond to changes in cardiac structure and function associated with elevated filling pressures. This may in turn have prognostic as well as therapeutic implications.

Lung

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2001;

10

TISSUE DOPPLER ECHOCARDIOGRAPHY PROVIDES NEW INSIGHTS INTO LEFT VENTRICULAR LONGITUDINAL FUNCTION FOLLOWING EARLY REPAIR OF ISOLATED COARCTATION OF THE AORTA. X.0. Liu’, D.M. Coleman”. L.C. Wilkinson’. M. Newton’, G.D. Gamble2. I.L. WilkinsonI. ‘Cardiology Department, Royal Children’s Hospital, Melbourne, Vie., Australia; ZDepartment of Medicine, University of Auckland, Auckland, New Zealand Purpose: To investigate whether pulsed tissue Doppler echocardiography (TDE) provides new information about left ventricular (LV) longitudinal function following adequate early repair of isolated coarctation of the aorta (CoA). Methods: Pulsed TDE of the medial (MMA) and lateral (LMA) mitral annulus in the apical 4-chamber view and conventional echocardiography were performed on 16 patients [mean age 11.6 (SD 3.0) yrs, wt 39.1 (SD 12.0) kg, 12M] who had undergone coarctation repair. The mean age at operation was 87 days (range O-357) and mean follow-up period 11.6 (SD 3.0) yrs. No patient had clinical or echocardiographic evidence of residual or recurrent coarctation. Comparison was made with a control group of 20 normal children [mean age 12.9 (SD 3.8) yrs, wt 48.1 (SD 15.9) kg, llM]. Results: All results are expressed as mean&EM. There was a decrease in the MMA peak systolic velocity (6.9eO.2 vs 7.9+0.2cm/s, p=O.O06) and peak early diastolic velocity (Ea, 14.3kO.6 vs 16.4+0.7cm/s, p=O.O27) and a borderline decrease in the LMA peak systolic velocity (8.9kO.5 vs 10.1+0.4cm/s, p=O.O57) in the patients compared to controls. The LV shortening fraction (37.2k1.3 vs 32.0+0.9%, p=O.O02) and mitral inflow peak E (110+4 vs 89+5cm/s, p=O.O02) and peak A (49+4 vs 34r3cm/s, p=O.O03) velocities were increased in the patient group but the E/A ratio was not significantly different between the 2 groups. The mitral inflow/annular peak early diastolic velocity ratio (E/Es) was increased for the medial (16.1+0.8 vs 11.4+0.7cm/s, p
CLINICAL FEATURES PREDICT ECHOCARDIOGRAPHY RESULTS IN SUSPECTED ENDOCARDITIS: A SERIES OF 500 CONSECUTIVE CASES. D. Mou*. A. Patel. D.S. Celermaier. Department of Cardiology, Royal Prince Alfred Hospital, Sydney.

A COMPARISON OF MORPHOLOGICAL FEATURES IN INTERRUPTED AORTIC ARCH WITH COARCTATION. A.L. Calder,* C.1. Occleshaw, B.R. Cowan. Green Lane Hospital and School of Medicine, Auckland, New Zealand

Screening for suspected bacterial endocarditis (BE) is a common indication for inpatient transthoracic echocardiography, but is a “low yield” investigation. We studied 500 consecutively referred patients to assess the relationships between clinical features and echocardiographic results in a teaching hospital department. “Risk factor” assessment for each patient included intravenous drug use (IVDU), known congenital or rheumatic disease, prosthetic valves, central venous line, embolic phenomena, presence of recurrent fevers, blood culture results and recent use of antibiotics. 295 male and 205 female subjects aged 5424 (36-68) years were included. BE was confirmed on echo in only 43/500 cases (8.6%). Of these, endocarditis was found on the mitral valve in 10 patients, aortic valve in 15 patients and tricuspid valve in 10 patients. There were 4 patients who had endocarditis involving more than one valve, 1 patient with Eustachian valve endocarditis, 2 patients with pacemaker wire endocarditis and 1 patient with a vegetation seen in the conduit for complex congenital heart disease. The most significant predictors of BE on multivariate analysis were recent embolism (odds ratio 414,95% confidence interval 57.3028, p< 0.001); central line in-situ (OR 87,95% CI 9-837, p< 0.001); intravenous drug use (OR 22,95% CI 3-159, p=O.O02); positive blood cultures (OR 7.4, p= 0.01) and presence of a prosthetic valve (OR 14, p= 0.03). Of the 239 patients without any of these 5 risk factors, none had BE; furthermore, none of the 43 BE patients had O/5 of these risk factors (negative predictive value 100%). The most sensitive risk factor for BE was positive blood culture (90%; specificity 68%) and the most specific were embolism (98%; sensitivity 77%) and presence of a central line (98%; sensitivity 17%). Therefore in this study, nearly half the patients referred had no identifiable risk factors for BE and none of these had vegetations noted on echocardiography. Judicious clinical selection might improve the use of cardiac ultrasound for this indication.

Obstruction of the left ventricular outflow (LVO) may be a serious problem in patients with coarctation of the aortic isthmus (Coarct) or interruption of the aortic arch (IAA). Measurements made in heart specimens from 31 infants with Coarct and 16 with IAA (type B in 11, type A in 5) were compared with normal. Seven cases were scanned with 3D MRI. All 47 cases had situs solitus of atria, concordant atrioventricular connections and normally connected great arteries. Bicommissural aortic valves were found in 11 (35%) with Coarct and 50% with IAA. The average aortic valve circumferences = 2.6 + 1.3cm in Coarct group and 2.1 f 0.8cm in L4A cases (NS) and were not significantly different from normal. The mean circumference of LVO in Coarct group = 1.7 f 0.5cm and in IAA group = 1.5 f 0.3cm. Ventricular septal defects were found in 22 (71%) of cases with Coarct and in all with IAA. All cases with IAA had LVO obstruction whereas this was found in 18 (58%) with Coarct. Only l/9 case with Coarct and intact ventricular septum had LVO obstruction. Types of Subaortic Obstruction*: Encroachment by Superior Muscle Overriding Aorta Poor expansion of LVO

Subaortic ridge Displaced Conal Septum

Coarct Group

IAA Group

10 (31%) 4 (13%) 3 (9%) 2 (6%)

11(35%) 0 7 (23%) 9 (29%)

0

NOtIe 13 (42%) ‘More than one type present in several cases, especially IAA

4 (13%) 0

The MRI scans give insight into understanding the various types of LVO obstruction, which could lead to improved diagnosis and surgical treatment.

Heart,

Lung

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49th

2001; 10

M-MODE TISSUE DOPPLER ECHOCARDIOGRAPHY MAY BE USEFUL IN DETECTING CELLULAR REJECTION IN PAEDIATRIC CARDIAC TRANSPLANT RECIPIENTS. D.M. Coleman”. M. Newton’. R.R. Restall’, A. Shippl, G.D. Gamble*. C.W. Chow’. R.G. Weintraub’, ‘Cardiology Department and Department of Anatomic Pathology, Royal Children’s Hospital, Melbourne, Vie., Australia; 2Department of Medicine, University of Auckland, Auckland, New Zealand. Objective: To investigate whether M-mode tissue Doppler echocardiography (TDE) of the left ventricular posterior wall (LVPW) detects the presence and degree of cellular rejection in paediatric cardiac transplant recipients. Methods: Thirty-six TDE studies were undertaken in 8 patients: median age at transplantation 9.Oyr (range 1.7 to 21.3), median post-transplant interval 2.3mth (range 0.3 to 74.2), 5 males. All TDE studies were performed within 24 hours of an endomyocardial biopsy by an observer blinded to clinical and histological findings. Transmural maximum mean velocity (MMV) and maximum velocity gradient (MVG) and the time (Ti) to these values from the onset of the QRS complex were measured during ventricular ejection (ve), rapid ventricular filling (rvf) and following atria1 contraction (ac). Results: Eleven biopsies were ISHLT histological grade 0,13 grade 1,6 grade 2 and 6 grade 3. Univariate analysis revealed MVGrvf to be the only parameter that correlated significantly with rejection grade (I = -0.39, p = 0.02). Mean MVGrvf differed for rejection grades 0 to 2 vs grade 3 (mean t SEE: 8.3 + 0.7/s vs 5.5 * 1.0/s, p = 0.08). In multivariate analysis TiMVGrvf was the only significant independent predictor of rejection grade (p = 0.025). A cut-off level of 8.1/s for MVGrvf yielded a sensitivity of 83% (95% CI: 54, loo), specificity of 43% (95% CI: 25, 61) and negative predictive value of 92% (95% Cl: 78, 100). No other TDE parameter nor LV shortening fraction, LV mass, isovolumic relaxation time, E/A ratio, E deceleration time was significantly associated with rejection grade (all p > 0.13). Conclusion: MVGrvf and TiMVGrvf of the LVPW by M-mode TDE may be useful for non-invasively determining the need for endomyocardial biopsy in children and adolescents following cardiac transplantation.

Annual

Scientific

Meeting

of CSANZ

A145

WALL STRESS MISREPRESENTS AFTERLOAD IN VENTRICLES WITH ABNORMAL CHAMBER GEOMETRY. T.L. Gentles.’ S.D.Colan. Department of Paediatric Cardiology Green Lane Hospital, Auckland, New Zealand and the Department of Cardiology, Children’s Hospital, Boston, USA. Background: Wall stress (WS), although commonly used as an index of LV afterload, fails to take into account forces generated within the wall that oppose fiber thickening during contraction. As a result, WS may misrepresent average fiber stress (FS) - the actual shortening force exerted by individual fibers - particularly in the presence of an abnormal thickness:dimension ratio. Methods: Echocardiograms were obtained in 4 groups of children and young adults (age 12.7 + 6.0 years) with a wide range of values for LV mass and/or end-diastolic thickness:dimension ratio (h/D). Diagnoses were: aortic stenosis (AS), s/p coarctation (COA), s/p adriamycin treatment (ADR), and severe aortic and/or mitral regurgitation (AR/MR). End-systolic WS and FS, LV mass, and h/D were calculated and expressed as z-scores relative to a normal population (n=305). Results: There were significant differences between WS and FS in all groups excepting ADR (Table). The difference between WS and FS z-scores was extreme when h/D was elevated (WS << FS) or reduced (WS >> FS) (WS - FS = 0.6 *(h/D)-lm 4.16, r=0.82, p
AS h=52) 3.2 + 2.9’ 2.0 t 1.8’ -4 0 * 1.3’ -2.8 * 1.2*+

COA 0.2 f 1.0 t -0.7 *

(~57) 1.6 1.4’ 2.1”

-0.1 t 1.8’

ADR (~47) -0.6 t 0.9’ -0.3 f 0.9” 0.0 t 1.6

AR/MR (~51) -1.6 t 1.1’ 4.8 + 3.0’

0.0 + 1.3

3.1 * 3.5’ 2.1 + 2.4’+

* ~~0.05 compared to normal population. + ~~0.05 WS compared to FS.

Conclusions: Fiber stress, the force opposing fiber shortening, is overestimated by WS in thin walled ventricles and underestimated by WS in thick walled ventricles. Because of this, results of stress-shortening analysis on WS will be invalid in patients with abnormal ventricular geometry,

based

A146

Author Index 49th Annual Scientific

Heart, Meeting

49th Annual * Presenting

Author

Abemethy, M. J. A104* Abhayarama, W. A105’ Abraham, A. A71 Adsett, M. C. A133* Afridi, I. A96 Aggarwal, A. A56,75,75* Ahlers, B. A. A68 Ainsworth, B. A86 Ajani, A. E. A93*, 96*, 105’ Allada, C. S. A76*, lOO* Allan, R. A97,98 Allen, S. A66 Allman, K. C. A104 Al-Mubarak, N. All0 Alred, D. All0 Anderson, D. A102 Anderson, J. A73,86 Anderson, M. J. A76* Andrew, M. J. A66*, 67* Andrews, D. A64 Angelides, S. A97,98 Amolda, L. A81 Amolda, L. F. A68,74,83”, 87 Aroney, C. N. A71*, 133,135 Arronis, C. A109* Arthur, J. F. A108 Ashby, D. T. A142* Asher, C. R. A96 Ashton, N. G. A102 Autelitano, D. A115 Aylward, I? E. A68,74 Ayre, I’. A73 Azariah, I? A58 Badimon, J. J. A123,133 Bagg, W. Al43 Baglin, T. A123,124 Baguet, J-P. A118 Baker, R. A. A66,66’, 67 Balaban, K. W. A70 Balazs, N. A71 Baldi, M. A60,llO Baldi, M. A. A98,119 Bamroongsuk, V. A95,140 Bannon, I? A61 Bao, M. Al25 Barin, E. A75 Barlow, M. A62,95 Barlow, M. A. A63*, 94*, 136,141* Baron, D. A105,133

Lung

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2001; 10

of CSANZ

Author Index Scientific Meeting of CSANZ Barron, G. J. All0 Barter, I? A85,137 Bashein, G. Al22 Bashir, M. A70,96 Bastiaana, 8. All4 Bastian, B. Al33 Bateman, I? Al39 Battinelli, E. M. A89 Bauskin, A. A&2,87 Bayfield, M. A61 Bebbington, J. Al01 Beckert, L. A68 Beers, J. A. A79 Begg, J. A73 Begg, S. A86 Beilin, L. J. A106 Bellamy, G. Al33 Beller, E. A86 BeIIer, E. M. A85*, 136 Beltrame, J. F. Al28 Bendeich, M. M. A69,114 Benjamin, W. Al01 Benson, V. L. All8 Berakis, A. A77* Bergin, I? A56,75 Bergin, I? J. All3 Bemdt, M. C. A108,112 Bersten, A. D. A68,74 Best, J. A85,86,136 Best, J. D. A85,106,121,139 Best, M. A129,139 Best, S. A61 Bett, J. H. N. A71,85* Biben, C. A78 Biegelsen, E. S. A85 Bijnens, 8. A65,93,122,126,127,143 Bilsborough, W. A89* Binasis, A. A75 Binnekamp, M. A70* Bjomerheim, R. A79 Bjomstad, I? G. A79*, 103’, 117* Black, I. A75 Bladen, J. A61 Blake, R. J. A90 Blanton, C. A107 Blue, L. All5 Bobik, A. A108,112 Bolson, E. L. A121 Boone, J. B. A63,94 Booth, V. A. A139* Boxall, J. A98 Boyd, A. A63

Boyd, A. C. A58’, 63,70,82 Boyle, A. J. A77’, 96 Braatvedt, G. Al43 Bradfield, R. Al36 Bradshaw, I? J. A67’, 106’, 120,120,137 Brady, I? A68 Bray, J. E. A86*, 89* Breit, S. A&2,87 Breit, S. N. A84 Brennan, C. All0 Brennerman, I? A66 Brieger, D. A71*, 102 Brieger, D. B. A130 Briffa, T. A138* Briggs, J. M. A56,87 Broughton, A. A75,97 Browett, I? J. Al00 Brown, M. A. A106 Bruce, D. A130 Buick, D. Al38 Bunker, S. A58,138* Bums, N. A57* Bursill, J. A84,87 Burstow, D. A73’, 128 Burstow, D. J. A72*, 111,133,135 Bush, V. A104 Butler, N. A140 Buxton, B. F. A67*, 72 Byth-Wilson, K. A63 Cadd, I? A58 Cain, I’. A65*, 81,123*, 124*, 125,126 Calder, A. L. A78*, 144* Cameron, J. D. A83*, 83,117,118, Cameron, L. D. Al38 Campbell, C. A63,141 Campbell, T. J. A84 Campbell, T. A84,87 Capewell, S. A107 Carey, H. A99 Carey, M. F. A76,140 Case, C. A65,66,123, Cass, D. All7 Castagna, M. A105 Cehic, D. A. Al42 Celermajer, D. A99,131 Celermajer, D. S. ASO, 90,91,99,130,131, 132,136,144 Chai, Y. Y. All1 Chan, L. F. Al39 Chan, L. L. T. A118,132 Chan, S. W. Al32

Heart,

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2001; 10 49th Annual

Chan, T. Y. K. Al32 Chan, W. W. Al39 Chard, R. A64 Chard, R. B. A58,63,70 Cheetham, C. A114*, 129 Chen, S. A108 Cheung, A. S. I? A118,132 Cheung, H. W. A139* Chin-Dusting, J. I? F. All3 Chirkov, Y. Y. A84*, 101 Chiu, C. W. All8 Cho, S. Y. A98 Chook, I’. A118,132 Choong, C. K. A79* Chow, C. W. Al45 Chung, M. A62 Clark, A. T. A94 Claus, I? A93,143 Clear, S. A57 Cleary, S. R. A57* Cohen, G. A86 Colan, S. D. Al45 Cole, C. A62 Cole, T. J. A118 Coleman, D. M. A144*, 145’ Colman, I? A86 Colon-Hernandez, I? J. A97,133 Colquhoun, D. A107,120,131,136,137’ Colquhoun, D. M. A91*, 108*, 108 Conaglen, I? J. A71* Connolly, S. J. A63,94 Conry, L. Al39 Constantinou, K. A57 Cooke, G. Al00 Cooper, S. A64 Corcoran, S. Al36 Corti, R. A123,133 Coutinho, 8. A104 Cowan, B. R. A103,104,117,123,124, 125*, 144 Cowley, A. A69 Cowley, A. J. All3 Cranney, G. A69,70,119 Crilly, J. A56’ Crimmins, D. S. A88 Crittenden, J. A120 Crozier, J. G. A98 Curran, D. H. A88 Cutright, W. J. A102 D’Arcy, S. A140 D’hooge, J. A65,93,122,126,127,143 D’Orsa, K. A61 da Silva, 0. B. A65, 127 Dahl, M. A56,57 Daly, J. A69,114 Dan, A. Al33 Dart, A. A75,84 Dart, A. M. A83,106,118,139 Das, A. Al36

David, E. J. A56 Davidson, M. A91,92 Davidson, I? A113 Davidson, I? M. A59,69,114 Davis, 8.8. A61 Davis, L. A88 Davis, L. M. A76*, 94’ Davis, M. J. E. A141* Davis, S. Al00 Daws, K. A60” Daws, K. J. A59* de Jong, S. A. A109 de Kretser, D. M. A130 De Pasquale, C. G. A58,68*, 74* Dean, R. A92 Death, A. A99 Death, A. K. A90,99 Dee, G. W. Al42 Delatycki, M. Al27 Dell’Italia, L. J. Al25 Dembo, L. A89,114 Denniss, A. R. A109,lll Detmer, I? R. Al22 Devitt, L. A59* Devlin, G. A71 Dewar, L. A82 Dick, R. A58 Dique, T. A89 Disney, P. J. S. Al42 Dobrolet, N. C. A103 Dodic, M. A80 Dommke, C. Al43 Dommke, Ch. Al27 Donaldson, L. Al38 Donelan, L. A122,127,143 Dooley, M. A121 Dorian, I? A63,94 dos Remedios, C. A107 Doughty, R. A60,104 Doughty, R. N. A57,74,82,115,116,140*, 143 Doyle, I. R. A68,74 Dresing, T. A62 Drury, I! A86 Du, X. A75 Duffy, S. J. A85*, lOO*, lOl* Dunlevie, H. A71 Dunne, J. S. A60* Dusting, G. J. All9 Dyble, W. A61 Ecclestone, R. J. Al00 Edwards, C. A138* Eipper, V A63,141 Elliott, D. A69, 114 Elliott, J. A71 Elliott, J. M. A72, 88*, 88,98, Ellis, C. J. A88*, lOl+, Emberson, J. Al36 Empson, M. All1

102*, 129’

Scientific

Meeting

England, J. F. A88’, Esler, M. A75 Esmore, D. S. A73 Esmore, D. A61 Espiner, E. A. A98 Evans, A. J. All3 Eyskens, B. Al22

Author Index of CSANZ

A147

91*

Faddy, S. Al33 Falconer, J. A88,88* Falconer, J. A. Al29 Fallon, J. T. Al33 Farouque, H. M. 0. A71,98”, Farshid, A. A105 Fathi, R. 8. A61*, 125*, 126’ Fayad, Z. A. Al23 Febbraio, M. A. A76 Feneley, M. A108,140,142 Feneley, M. I’. All8 Feng, J. Z. Al32 Ferguson, M. A57 Fermanis, G. A70 Fernandes, C. A92,105* Ferrier, K. E. A118 Finucane, A. K. A64,64”, 79 Finucane, K. Al35 Fisher, S. All6 Fitzpatrick, D. All1 Fogarty, A. M. A128,144 Fosse, E. A103 Fox, K. A. A. A71 Foxall, T. M. A89 Frampton, C. A72,98 Freedman, B. Al38 Frei, 8. Al00 French, J. Al38 French, J. K. AlOO*, 102,121 French, R. A78*, 117 French, R. A. A121,127 Friend, C. A97,98 Fuller, J. A67 Fung, K. C. A126* Fung, W. H. A118,139 Fuster, V. A123,133

119*, 123

Galbraith, A. All4 Gamble, G. AlOl, 115,116 Gamble, G. D. A57,82,140,143,144,145 Gan, T. E. A89 Gao, W. Z. Al00 Gao, X. A75 Garcia, M. J. A66,70,144 Garg, M. L. A90 Garlick, S. Al42 Garrahy, P. A61,65 Gasson, D. Al01 Gatzka, C. D. A118 Geary, G. G. A109*, 110 Geerling, R. H. A140

A148

Author Index 49th Annual Scientific

Heart, Meeting

Gelman, J. S. A122,127*, 135, 143 Gentles, T. L. A64,78,79,103,116,117*, 123*, 124,125,145* Gewillig, M. Al22 Ghao, W. A107 Gilfillan, I. A67 Glasziou, I? A131,137 Gokce, N. A85,lOO Goldschmidt-Clermont, I? Al00 Goodman, S. A102 Gordon, I. A67 Gordon, J. M. A119* Gould, I? A61 Graham, R, J. A122,143 Graham, R. M. A108 Grant, I? W. A69*, 111 Grant, I? A69,70 Grant, R. A68,74 Green, D. A74* Green, D. J. A89,114,129 Green, M. A63,94 Griffiths, K. A131 Griffiths, K. A. A90,91,136* Grigg, L. A80 Grigg, L. E. A106,116,139 Grout, D. A109,122,131 Grove, C. A92 Groves, N. A78 Gruberg, L. A93,105 Gunalingam, B. A105*, 133* Guy, D. J. A58,63*, 70 Haikerwal, D. A84*, 97,121 Hales, S. A75 Halmagyi, M. A91 Haluska, 8. A61,65,81”, 124 Hambly, B. D. Al28 Hamer, A. W. F. A95* Hamilton-Craig, I. A58 Handelsman, D. A99,131 Handelsman, D. J. A99,130,131 Hannan, R. D. All5 Hansen, I? S. A80,112 Harden, F. A. A91,108 Harding, S. A. A97,135 Hare, D. L. A72,76,95,106,121,139,140 Harper, R. W. A56,60,86,98,110,130 Harrap, S. B. A76 Harris, A. M. A135” Harris, I’. Al38 Harris, I? J. Al36 Hart, C. L. A115,120 Harvey, R. I? A78 Hastings, J. A75 Hata, M. A72 Hatle, L. A65,122,126,127,143 Hawker, R. A64 Hayes, A. A140 Hayes, H. M. Al39

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of CSANZ

Hayward, S. A130 Heald, S. A71 Heath, R. Al38 Heddle, W. A59 Helft, G. A123,133 Henderson, K. Al38 Herbots, L. A127,143 Hereford-Ashley, I? A95,136 Herregods, M.Ch. Al27 Hertzberg, S. All9 Hetmanski, D. A69,113 Hicks, B. J. A91,108 Hicks, M. Al42 Hilton, D. J. A82 Hilton, J. D. A94 Ho, B. A106,139 Ho, C. Y. A65,127 Ho, I? Y. A118 Holbrook, M. A85,100,101 Hole, D. J. A115,120 Holmes, A. S. A84,lOl Holmstrem, H. A79 Holst, D. A56*, 75” Holst, D. I’. All3 Holt, S. A80 Hood, M. A103,141 Hood, M. A. Al42 Hood, S. G. A119 Hope, S. A. A71*, A76*, A83*, 117* Hopkins, A. A105 Hopkins, A. I? A92 Hopper, L. A75 Horne, R. A88 Horowitz, J. D. A59,84,101,104,128 Horrigan, M. A93 Horsley, I? A108 Horton, D. A70 Hourigan, L. A. A142* Huang, Y. A68,77*, 77,78*, 107 Hughes, C. A61,73 Hui, S. Y. Al39 Hung, J. A120,137 Hungerford, J. All1 Hunt, D. Al37 Hunyor, S. A68*, 77,78,107 Ihlen, H. A79 Iliopoulos, J. All1 Ilton, M. A59 Inglessis, I. A97 Ingley, K. A74 Ip, M. L. Al39 Ip, S. Y. Al39 Iyer, S. S. All0 Jagannath, B. A64 Jalali, H. A64*, 79* Jamal, F. A65,122,126 James, N. A73 Jamrozik, K. A67

Jang, Y. A98 Jarman, J. I? A88 Jayaraman, C. A71 Jayne, K. A86 A85,106,121*, Jelinek, M. V Jennings, G. A108,112 Jennings, G. L. A82*, 118 Jennings, G. L. R. A106 Jepson, N. A97*, 98*, 109 Jepson, N. S. All1 Jeremy, R. W. Al28 Jessup, W. A90,92,130 Jiang, L. A107* Jirojwong, S. A57 Johnson, S. A58,138 Johnston, C. I. A106 Johnston, L. A68 Johnstone, L. A75 Jones, I? A69 Jones, I? G. Al01 Juergens, C. I? A92,105 Kachwalla, H. A92 Kalahasti, S. Al28 Kalman, J. M. A63,126 Kamran, M. A94 Karolis, C. A97,98 Kaye, D. A56,75 Kaye, D. M. A68*, 75,113 Kealey, J. L. A98 Keaney, J. F. Jnr A85,100,101 Keat, K. Alll’ Keech, A. A85,86,131,137,138 136 Keech, A. C. A91,136*, Kelly, R. Al33 Kent, K. A105 Kent, K. M. A93,96 Keogh, A. M. A76,100,140 Kerr, A. Al35 Kerr, A. R. A64,79 Kerr, C. R. A63,94 Kesteven, S. A108,142 Kesteven, S. H. L. A118 Khoury, V. Al26 Kim, D. H. A93 Kim, H-S. A93,96 King, L. A66 Kingwell, B. A. A83,118* Kini, A. S. A94 Kirby, A. Al37 Kizana, E. A112’ Klein, A. L. A66,128,144 Klein, G. A63,94 Klein, G. J. A141 Klinke, W. I? A94 Klungboonkrong, V. A81 Kneebone, A. C. A66,67 Knight, J. L. A66,67 Knittel, T. A97,98 Kockx, M. A92*

139

10

Heart,

Lung

and Circulation

2001; 10 49th Annual

Konta, T. A85 Kopsidas, G. A99 Kosiol, J. A58 Kotlyar, E. A140* Kotschet, E. A9T Kotylar, E. A76 Kovoor, I? A63,112,141 A65*, 126*, 127* Kowalski, M. Koyama, Y. AgO*, 112* Krahn, A. D. A63,94,141 Krawczyszyn, A. A97 Krawczyszyn, M. A75* Kritharides, L. A61, 92, 112, 126 Kroon, I? A. A91 Krum, H. A56,75,77,113,115,140 Kucia, A. M. A56,59,87 Kuipers, T. A74 Kukulski, T. A65, 126 Kull, A. A99 Kwan, J. A93 Kyung Jang, I. K. A97,135 La Gerche, A. A77 Lai, N. T. A91 Lainchbury, J. G. A68*, 72,98 Lam,C. A62 Lambley, J. A64 Lancaster, M. A58 Lane, G. K. A79*, 102*, 103*, Lange, A. A72,128 Langenfeld, M. A90 Langton, I? A92” Larbalestier, R. Al39 Latson, L. A. A79,102,103 Lattimore, J. L. A90” Lau, G. A112* Lau, J. T. F. Al32 Lau, K. C. A64 Law, D. A69,70 Law, T. C. A118 Lawrence White, R. A96 Le Brocque, S. I? A89 Le, T. Q. A67 Leahy, T. A120* Lee, K. H. A93 Lee, W. H. A93 Lefkovits, J. A71 Legget, M. E. A121,122*, 127 Leinbach, R. C. A97 Leitch, J. W. A90 Leitch, J. A62, 73, 95, 136 Leung, D. Y. C. A82 Levett, K. A58,87 Li,L. A131 Liew, C. T. A92” Liew, D. A86*, 86 Lim, E. K. A98 Lim, R. A65 Lim, S. A86*, 86 Lin, F. AlOB*

Lincoln, M. T. A104 Lindsay, G. All1 Ling, J. A90 Linnane, A. W. A99 Lintott, C. A86 Liu, 8. T. Y. Al32 Liu, I? A131 Liu, X. 0. Al44 Liu-Stratton, Y. Al00 Lo, C. C. Al39 Lo, S. T. A92, 105 Lonergan, D. A97,98 Lopez-Jimenez, F. A65,127 Loscalzo, J. A89 Lovett, M. Al39 Lowalski, M. Al43 Lowe, H. C. A92,105 Lui, L. S. Al39 Lund, M. A65*, 127* Lux, A. A82 Lydon, A. A102 Lyon, W. A61” Lytle, B. W. A70 Ma, P. A92” Macdonald, P. Al42 Macdonald, I? S. A76,100,140 MacDonald, S. L. S. A124* Macfarlane, L. A113* MacIntyre, K. A107 MacIntyre, C. R. All1 Maclsaac, A. A106 Macri, N. A102 Mahar, L. J. Al42 Mahdi, N. A. A97 Mahon, N. G. Al44 Mai, J. 2. Al32 Maiorana, A. A74,129* Malan, E. A89,lOO Mallat, M. Al00 Mallinson, G. D. A103,124* Manganas, C. Alll” Manglick, I? All7 Manning, M. A102 Marasco, S. A61 Mariani, J. A99 Marley, J. E. A106 Marrouche, N. A62 Marrouche, N. F. A62 Marschner, I. A131,137 Martens, N. A80 Martin, C. A68 Martin, J. A77 Martin, M. Al44 Marwick, T. A61,65,65*, 66”‘ 123,124, 125,126 Marwick, T. H. A81 Maspero, S. A75 Matalanis, G. A67 Mathew, T. H. A104

Scientific

Meeting

Author Index of CSANZ

A149

Mathur, G. A69*, 70,119 Mavaddat, L. Al29 McBurney, H. Al38 McCaffrey, D. A140 McCall, A. Al42 McCarron, H. C. K. Al28 McClelland, A. N. W. Al01 McCormick, M. P. A109,133 McCredie, R. J. Al36 McCrohon, J. A. A130 McDowell, J. Al00 McGaw, D. J. A130* McGrath, B. P. A83 McGrath, K. A99 McGrath, K. C. Y. A99 McGuire, A. A140 McKitrick, D. J. A83,87” McMahon, A. C. A118” McMurray, J. J. A107,115,120,140 McNally, C. Al39 McNeair, T. A58 McNeil, J. J. A86, 106, 139 McQuillan, B. A120 McQuillan, B. M. Al37 Medley, T. L. All8 Menzies, D. G. A140 Mercer, L. A75 71, 76, 83, 98, I 10, Meredith, I. T. A56,60, 117,119,123,133,135 Mertens, L. Al22 Mesia, C. I. A79,102,103 Miller, F. A99 Miller, J. C. A72 Milross, C. A97, 98 Minkoff, L. Al23 Minns, I. A86 Minson, J. B. A83,87 Mishra, K. J. A87” Misso, N. A92 Mitchell, S. A73 Mitre, C. A94 Modra, B. A58” Mok, K. Al33 Molenaar, P A79 Mond, H. A136* Morel-Kopp, M-C. A99 Morgan, J. A80* Morgan, J. G. A116* Morgan, T. 0. A106 Moritz, K. A80, 117 Morrison, C. E. All5 Morton, B. A75 Morton, J. B. A63,126 Moss-Morris, R. A88 Mottram, P. Al43 Mottram, I? M. A122,127,135 Mou, D. A80*, 144* Moyle, K. R. A103*, 124 Muhlmann, M. A77 Muhlmann, M. H. All8

A150

Author Index 49th Annual Scientific

Heart, Meeting

Muller, D. W. A105,133 Mulray, S. A107,120,137 Muncaster, S. A60*, 74’: 116 Murchie, K. A121* Murgatroyd, F. A141 Nagata, M. A89 Nagley, I? A99 Nair, S. A109,122,131 Najos, 0. Al26 Nakatani, S. A125,126 Nakhla, S. A90,90*, 130,131 Nasr, T. All1 Nataatmadja, M. I. A89 Natale, A. A62 Naughton, M. A77 Nelson, G. I. C. A80,112 New, G. AllO’ Newman, D. A69,70 Newman, D. C. A69,lll Newman, I? Al37 Newman, R. A102,106,139 Newport, S. A92,105 Newton, M. Al44,145 Ng, M. K. C. Alll, 130*, 131* Nguyen-Do, I? AlOP Nicholls, M. G. A68,72,98 Nicholls, S. A62’, 73,95,133,136’ Nicholson, I. A58,63,64 Nicholson, I. A. A70’ Nidorf, S. M. A109*, 120,122,131 Niebauer, M. A62 Nishimura, T. A77 Nolan, T. C. All1 North, F. A120 Nunn, C. A71 Nunn, G. A58,63,70,117 Nunn, G. R. A64 O’Brien, M. A73,128 O’Brien, M. F. A72 O’Brien, R. C. All9 O’Connor, A. E. A130 O’Donnell, C. A79 O’Driscoll, G. A74,129 O’Driscoll, J. G. A89,114,129,139,141 O’Meeghan, T. A80 Oberklaid, D. A58 Occleshaw, C. A117,123 Occleshaw, C. J. A103,124,125,144 Ohman, E. M. A72 Onan, D. All5 Orsboum, G. A57 Ou, R. A61,99 Owens, W. A. Al08 Oxenham, H. C. A104* Palacios, I. F. A97,133 Palka, l? A72,128 Palmer, S. A78

Lung

and Circulation

2001; 10

of CSANZ

Paoletti, R. A133* Park, H. Y. A98 Park, K. S. A93* Parks, I. A75 Pamell, M. M. A68,113* Parsonage, W. A. A69*, 113*, 114’ Patel, A. Al44 Patterson, J. A140 Paull, G. A59* Pavia, S. A62’ Pavia, S. V. A62* Pearl, A. All6 Pears, J. Al33 Peeters, A. A86 Pepe, S. A61,99 Pereira, J. J. A66*, 70*, 96*, 128’, 144” Perry, K. A88 retch, J. A73 Petrie, K. J. A88,138 Petrovic, N. A92 Peverill, R. B. Al27 Peverill, R. E. A86,89, lOO*, 122,143* Philcox, S. A99 Phillips, D. J. A130 Pichard, A. A105 Pichard, A. D. A93,96 Pick, A. A61 Pitney, M. A97,98,109 Plekhanov, S. A68 Plunkett, J. C. A71 PohLner, I? A64 Pohlner, I? G. A79 Pohorence, J. Al00 Pomerantsev, E. A97 Pomfret, J. All6 Pont, K. A73 Poon, I? Y. K. Al32 Poon, Y. M. Al39 Porrazzo, M. A96 Powell, A. C. A141 Prasan, A. M. A128* Pratt, J. A105 Premawardhana, U. A80 Prieto, L. R. A102 Prior, D. L. A66,77,128,144 Prior, D. A56,75,121 Prosser, I. A105 Pullan, A. J. Al27 Qi, A. A63,94 Qiao, M. A132,132* Quinn, J. E. A104 Rabinov, M. A61 Rahman, S. Al28 Raman, J. A67, A72* Ramananthan, K. Al38 Ramanathan, T. A77,77*, 78 Ramsay, D. A108,113 Rasmussen, H. H. A80,112

Raza, A. A92 Reed, E. A83 Rees, D. A70,113* Rees, D. M. A59 Reid, C. M. A82,106* Restall, R. R. Al45 Rhodes,J. E A79,102,103 Richards, A. M. A68,72*, 88,98*, 129 Richards, M. All6 Richardson, M. A56,59,75,113 Riddell, F. A135,142 Ritchie, G. A86* Ritchie, H. All9 Ritchie, R. H. A119* Robb, B. J. A88 Robertson, M. A109 Rodriguez-Alemparte, M. A97,133 Ronaldson, R. Al01 Rosalion, A. A67 Rose, M. A88 Rosenfeldt, F. L. A61,73*, 99’ Rosenhain, S. Al38 Rosenkranz, A. C. All9 Ross, D. L. A58,63,70,82,87,109,110, 11,112,141 Roubin, G. S. All0 Roy, I? A105,133 Roy, S. A69,70*, 119” Rubin, G. All1 Rubinstein, A. A93 Ruengsakulrach, l? A67 Russ, G. R. A104 Ryan, J. A142’ Ryan, P. A106 Ryu, S. K. A98” Sader, M. A99*, 131* Sader, M. A. A99* Saliba, W. A62 Sanchez, I? L. A97,133 Sanders, I? A63’, 126* Sanderson, J. E. A118,132,139 Sands, G. B. A127* Satler, L. A105 Satler, L. F. A93,96 Savage, L. A62 Saw, W. A62,73*, 95*, 95,133,136 Sawada, S. A66 Sawtell, F. D. A121 Sawyer, l? A102 Scalia, G. Al28 Scalia, G. M. Alll*, 114,133 Schenke, A. Al24 Schiller, N. B. A82,87 Schindeler, A. A78 Schmid, D. A121 Schumer, W. A93’ Schweikert, R. A62 Scotcher, J. All1 Scott, D. A120

Heart,

Lung

and Circulation

2001; 10 49th Annual

Scott, R. A85,86 Sculthorpe, A. B. A58 Searancke, K. A. A135* Seaton, D. A128” Sebastian, C. A71 See, F. A115 See, P. L. A56*, 60*, llO* Selig, S. A76,140 Sellick, K. A59 Selva-Nayagam, J. A81* Seo, J. K. A93 Sergeant, P A93 Setty, S. I? A64 Shameem, R. A80* Shameen, R. Al28 Shanahan, C. L. A116* Sharma, S. K. A94 Sharpe, N. A57,74,82,104,115,116,140, 143 Sharples, K. A107,120 Sheehan, F. H. A121 Sheeran, F. A61 Sheldon, R. A63,94 Shields, A. A57” Shim, W. H. A98 Shinnar, M. Al23 Shipp, A. Al45 Shirota, K. A77,78 Sholler, G. A64 Short, L. A61,65,81,124 Silaruks, S. A81* Simes, J. A107,120,131,137,137* Simes, R. J. A85,86 Simmons, L. A. A65,93”, 122*, 126,127, 143* Simpson, C. S. A141 Sindone, A. I? A69*, 114* Singarayar, S. A84,84*, 87* Singleton, C. A59 Skanes, A. C. A141 Skilton, M. A131 Skilton, M. R. A90,91* Skinner, J. R. A64,103*, 116,135,141’ Skinner, J. Al24 Skinner, M. I? A112 Skyrme-Jones, R. A. S. Al35 Smevik, B. A103 Smith, I. A73 Smith, J. A. A61,73 Smith, l? M. A94 Smith, W. M. A142’ Smith, W. A103,141 Smolich, J. J. A86,100,122*, 130 Smyth, D. W. A88 Solomon, S. D. A65,127 Somerset, S. A108 Sommers, D. A58 South, K. A59* Southworth, H. Al33 Sparks, P 8. A63,126

Meeting

Author Index of CSANZ

Thomson, L. E. J. A104* Threlfall, F. M. Al36 Thrupp, S. Al25 Thurston, N. A58* Tie, H. A84,84*, 87 Tirimacco, R. A66 Tofler, G. H. A75,99* Toia, D. A95,140 Tonkin, A. A107,120,137 Tonkin, A. M. A136,137* Toogood, G. A75 Toth, A. H. A79,103 Trim, G. A62,73,95,95’, Trivedi, S. A133* Troughton, R. W. A68,98 Tsakonis, H. A75 Tsui, W. H. Al39 Turner, J. G. A72,98 Turner, S. P A128* Tzanidis, A. A115*

Staff, M. A75 Stake, G. All7 Stanton, K. A89 Starling, R. C. Al44 Starr, J. All3 Steel, T. R. Al00 Stein, E. A91 Stepien, J. M. A84 Stevens, M. E. A108 Stevenson, I. A83 Stewart, J. Al42 Stewart, P A91 Stewart, R. A107”, 120” Stewart, R. A. H. Al38 Stewart, S. A107*, 115”, 120*, 140* Storer, M. A72 Strotman, J. Al27 Strutt, K. L. A91 Sue, C. M. A88 Sullivan, D. R. A91,136 Sullivan, D. A92 Summers, K. M. A89 Sutherland, G. R. A65,93,122,126,127, 143 Sutherland, R. Al36 Sutherland, W. H. F. A109 Swanney, M. P A68 Swerdloff, P. AlOO, 101 Szto, G. A61 Szymanski, D. Al00 Talajic, M. A63,94 Tan, H. C. Al26 Tan, H. A112 Tan, R. P. A94* Tanous, D. AllO” Tansley, G. A73 Tantikosum, W. A81 Taskinen, M-R. A85 Tatsanavivat, P A81 Tay, D. B. A83 Taylor, A. J. A108*, 112* Taylor, A. Al26 Taylor, B. A99 Taylor, R. A74 Taylor, R. R. A89,114 Tchou, P. A62 Thambar, S. Al33 Thelander, J. All1 Thiagalingam, A. A63*, 87,141* Thinkhamrop, B. A81 Thomas, J. D. A66,70,96,128,144 Thomas, L. A58,82*, 87* Thomas, S. P A58,63,70 Thomas, W. G. All5 Thompson, P. J. A92 Thompson, I? L. A67,106,107*, 120’, 122,131,137* Thomson, D. A73

Scientific

Unger, Uther,

133”, 136

S. A. A104 J. 8. A112,141

Vale, M. J. A85”, 106’, 121,139* Valeri, C. R. A89 Valgimigli, N. A56* Vallely, M. A61* Van de Water, N. S. Al00 Vasey, C. A66 Viles, A. A91 Vita, J. A. A85, 100, 101 Vitek, J. J. All0 Vlassak, I. A66 Vohra, J. K. A63,126 Vos, T. A86

109,120,

Wagstaff, J. All0 Waksman, R. A93,96,105 Walker, A. All5 Walker, P. J. A89 Walker, R. G. T. A109,122”, 131* Walker, S. 8. A57 Wallace, E. A63 Wallace, S. A93 Walsh, C. R. A97 Walsh, H. J. A57*, 74, 82, 143 Walsh, W. A119 Walters, D. L. A97*, 133*, 135’, 142 Ward, C. A99 Watanabe, T. A89 Watterson, I? A73 Watts, K. A129* Webber, 8. J. Al32 Webster, J. A59 Weerasooriya, H. R. A141 Weerasooriya, R. A89 Weidemann, E A65,122,126,127,143 Weinman, J. Al38 Weintraub, R. G. Al45

A151

Al.52

Author Index 49th Annual Scientific

Heart, Meeting

Weiss, B. A70 West, M. J. A73,89’, 106 West, T. A79,120 Whalley, G. A. A57,82*, 143* Whelan, A. I? A109*, 133* Whitboum, R. A106* White, H. A107,120,137 White, H. D. A72,100,101,102,121,129, 132,138 Wilcox, I. A90,139 Wilkes, E. A106 Wilkes, T. A120 Wilkins, G. T. Al33 Wilkinson, J. L. A116,144 Wilkinson, L. C. Al44 Will, I’. M. A91, 108 Williams, A. A76, 131 Williams, A. D. A140* Williams, B. F. A121* Williams, M. J. A. A109, 133 Williams, T. A77 Williamson, B. A61* Willoughby, S. R. A89* Wilson, A. M. A77 Wilson, M. A96*, 142 Wilson, N. J. A64*, 116 Wiltshire, A. A74 Wing, L. M. H. A106 Winlaw, D. A64* Winlaw, D. S. A117*

Lung

and Circulation

of CSANZ

Wintour, M. A117 Wintour-Coghlan, M. A80 Wishart, S. A131 Withy, S. Al27 Wolfe, R. A56,86 Wolfenden, H. A69,70 Wolfenden, H. D. A69,lll Wong, A. A92,105 Wong, C. K. A72*, lOl*, 129*, 132” Wong, H. S. I? All4 Wong, J. A80 Wong, M. A61 Wong, S. l? A102*, 121* Wong, S. Y. Al39 Wong, W. C. Al39 Wongvipaporn, C. A81 Woo, J. L. F. Al32 Woo, K. S. A118,132,132*, 139 Wood, C. A. A139* Woodard, J. A73 Woodcock, E. A. A108 Woods, R. L. All9 Woolley, N. A60 Worthley, M. I. AlOl*, 104) Worthley, S. G. A56,60,71,98,110,119, 123*, 133+, 135” Wouters, P. A93,143 Wowk, M. A61 Wright, S. A82 Wright, S. l? A74,115*, 116*, 140

Wu, W. A84,87 Wyse, K. A84,87 Xu, S. L. Y.

Al32

Yandle, T. G. A68,72,98 Yandle, T. All6 Yates, V. All0 Yee, R. A63,94,141 Yeoh, T. A69,78*, 114 Yeoman, D. J. A109 Yip, T. W. C. A118* Young,A. A. A103,104,117,123,124,125 Young, G. D. Al42 Young, K. All0 Young, I’. A85136 Young, W. J. A121 Yu, C. C. A73’ Yuasa, T. A77,78 Yuda, S. Al26 Yut, H. Al25 Zahn, E. M. A102,103 Zecchin, R. I? Alll* Zeitz, C. J. A87 Zeng, B. A130* Zhang, C. A99 Zhang, M. J. A119 Zheng, X. A77

2001; 10