The Journal of Heart and Lung Transplantation Volume 20, Number 2 239 PRELIMINARY EXPERIENCE WITH IVUS IN PEDIATRIC HEART TRANSPLANT RECIPIENTS J. Costello1, D. Wax2, C.L. Backer1, C. Mavroudis1, E. Pahl1; 1 Northwestern University Medical School, Chicago, IL; 2 Children’s Memorial Hospital, Chicago, IL, USA Post-transplant coronary artery disease (PTCAD) in children leads to late mortality and may be underdetected by coronary angiography (CA). Intravascular ultrasound (IVUS) for PTCAD surveillance has been advocated in adults, but is not routine in children. The purpose of this study was to review our initial experience with IVUS in this cohort. Procedures: Since 1/1/1998 we have performed IVUS in transplant recipients ⬎12 y/o undergoing annual CA. Following baseline CA, IVUS was performed using a 7Fr guide catheter to place a 3.2 Fr ultrasound catheter in each coronary artery. The presence and extent of PTCAD were quantified by determining the maximal intimal thickness (MIT) and highest Stanford score (0-4) for each coronary artery examined. IVUS findings were compared with selective CA. Serial studies were compared and complications were recorded. Results: A total of 25 IVUS studies were performed in 16 pts. Age at IVUS was 18.0⫹/-2.9yrs (12-23yrs); wt. was 59.2⫹/-15.4kg (34-87kg); time since transplantation was 4.3⫹/-2.3yrs (1-9yrs). (Table 1). Follow up IVUS over a 1-2 yr period was available for 10 coronaries in six pts. The Stanford score increased in 5/10 coronaries; the MIT increased in 7/10 coronaries. Complications included 1) a cardiopulmonary arrest in a 13y/o pt due to coronary air embolus during LCA IVUS; she was resuscitated and completely recovered; 2) two pts had prolonged ST elevation (ⱖ 30 minutes) and were monitored overnight. Eight others had transient ST changes. Conclusions: IVUS is much more sensitive than CA in detecting the presence and progression of PTCAD in children. Abnormalities were detected in the majority of pts; however, IVUS may lead to additional complications. Since the clinical utility has not been demonstrated, IVUS should remain investigational in pediatric pts. Table 1 Abnormal CA Abnormal IVUS Stanford score MIT
Left coronary artery
Right coronary artery
3/21 (14%) 20/21 (95%) 2.00⫹/-0.95 0.39⫹/-0.30
2/19 (11%) 17/19 (90%) 1.58⫹/-0.28 0.28⫹/-0.32
240 TWELVE YEAR EXPERIENCE WITH PEDIATRIC CARDIAC RETRANSPLANTATION K.R. Kanter, R.N. Vincent, A.M. Berg, V.K. Tam; Emory University School of Medicine, Atlanta, GA, USA Purpose: Although cardiac transplantation has become an accepted treatment option for children with end-stage or inoperable heart disease, experience with pediatric retransplantation is limited. Outcomes should be inspected to insure proper use of limited donor hearts. Methods: Since 1988, of 114 pediatric heart transplantations, we performed 10 retransplants (8.8%) in 9 children. One retransplant was for acute graft failure; the remainder were for chronic rejection or graft coronary artery disease. The mean age was older in the retransplant group (12.0 ⫾ 5.2 yrs. vs 6.9 ⫾ 5.9 yrs.; p ⫽ 0.01). The interval from primary transplant to retransplant ranged from 2 days
to 10 yrs. (mean 4.6 yrs.). Initial diagnosis was idiopathic cardiomyopathy (vs congenital heart disease) more commonly in the retransplant patients than in the primary transplant patients (56% vs 33%; p ⫽ NS). The retransplant patients were clinically more ill at time of transplant (UNOS Status I 80% vs 57%; mechanical circulatory support 30% vs 3%; retransplant vs primary). Results: There were no statistically significant differences between retransplant and primary transplant patients with regard to donor ischemia time, cardiopulmonary bypass time, days on the ventilator, days on inotropic support, ICU stay, or hospital stay. Retransplant patients were less likely to be free of rejection at 90 days compared with primary transplant patients. Actuarial survival was not statistically different out to five years (see Table). Conclusions: Cardiac retransplantation can be performed in children with early results comparable to primary transplantation despite a higher level of clinical acuity in the retransplant children. These results suggest that cardiac retransplantation in children is a reasonable therapeutic option. Actuarial Patient Survival Primary Retransplant
241 INVASIVE PNEUMOCCOCCAL INFECTION IN PEDIATRIC HEART TRANSPLANT PATIENTS S. Stovall, K. Ainley, E. Frazier, W. Morrow, G. Schutze; Arkansas Children’s Hospital, Little Rock, AR, USA Significant morbidity and mortality result from bacterial infections in pediatric cardiac transplant (HTx) patients. Streptococcus pneumoniae (S pn) is the most common bacterial pathogen in childhood. Methods: We sought to better define the role of S pn as a cause of invasive disease in HTx patients. The HTx database and records of all HTx patients at our facility were reviewed to examine Spn infections post transplant. Demographic and clinical data were reviewed as well including outcome and morbidity. Results: 80 patients were studied; 76 patients had HTx at our institution. 42 patients were male. 60 patients were Caucasian (C), 18 were African-American (AA), and 2 were of other races. 53% percent of patients were diagnosed with congenital heart disease prior to transplant (CHD). 9 (11%) patients had 12 episodes of Spn bacteremia; 3 suffered 2 episodes. 2/3 of these patients were AA and the rest were C. Six underwent HTx for cardiomyopathy and 3 for CCHD. None had known asplenia. Affected patients had an average age of 9 months (2 wks - 2 yrs) at HTx. Spn infections occurred 3 to 48 mons after HTx (mean: 22 mons, median: 20 mons, S.D.: ⫹/- 12.5 mons). Patients that were AA and those transplanted before 2 yrs of age were more likely to develop invasive infections (p⬍0.003). In only 3/12 episodes the patient was taking. Serogroup data included groups 19F, 14, 12, and 6A. Only 2 patients recieved the polysaccharide pneumococcal vaccine prior to their first. No deaths resulted from these episodes. Inferences: 11% of HTx patients had Spn bacteremia which is much higher than the incidence in the general population. Although most serious infections in HTx patients occur early after transplant, the Spn infections tend to occur later. Spn bacteremia is more common in AA patients and those transplanted at ⬍ 2 yrs of age, the age at which immunity to Spn normally develops. The use of the pneumococcal vaccines may be indicated post HTx in all patients but effectiveness remains to be determined.