ROLE OF ENDOMYOCARDIAL BIOPSY IN REJECTION SURVEILLANCE AFTER HEART-TRANSPLANTATION IN NEONATES AND CHILDREN

Objectives. The aim of this study was to retrospectively evaluate the sensitivity of noninvasive surveillance (physical examination, echocar diography) of rejection in accurately predicting histologically docume nted rejection episodes. Additionally, the usefulness of routine sched uled biopsy and its safety in pediatric patients was explored. Backgro und. Endomyocardial biopsy has been utilized as the standard for rejec tion surveillance after heart transplantation in adults, but its role in documenting clinically suspected rejection and in routine surveilla nce of pediatric patients has not been agreed upon. Methods. Heart tra nsplantation was performed in 14 neonates and 21 children. The immunos uppressive regimen consisted of cyclosporine, azathioprine and prednis one. All patients underwent routine noninvasive rejection surveillance that included clinical examination and echocardiography. In the neona tes, biopsy was performed quarterly beginning 6 months after transplan tation, after cessation of prednisone therapy. In the children, biopsy was performed 15 times in the 1st year. A minimum of five biopsy samp les were interpreted using the Working Formulation for Heart Transplan t Rejection. Results. In the neonates, 37 biopsies were performed. Evi dence of rejection was present in only three biopsy samples obtained d uring eight episodes (38%) of clinically suspected rejection. In 29 bi opsies performed when rejection was not clinically suspected, each bio psy was free of cellular infiltrate. In the children, 291 biopsies wer e performed. Evidence of rejection was present in only seven biopsies (41%) from 17 episodes of clinically suspected rejection. Cellular rej ection was discovered during routine rejection surveillance biopsies i n asymptomatic patients in 23 (8.4%) of 274 biopsies. Conclusions. In neonates with clinically suspected rejection, endomyocardial biopsy id entified which patients did not require rejection therapy. Endomyocard ial biopsy surveillance did not detect any unsuspected cases of reject ion. In children, noninvasive rejection surveillance was less reliable even in asymptomatic patients, suggesting that periodic endomyocardia l biopsy should be utilized.