238 made to develop noninvasive methods of detecting allograft rejection, 1-4 but the gold standard for detection of rejection remains the endomyocardial biopsy. 5 Most pediatric heart transplant centers have continued to rely on the endomy- ocardial biopsy for routine surveillance. There has been a push to abandon or se- verely limit the frequency of routine biop- sies after 1 year after transplant in the adult population. 6,7 This approach has not been adequately addressed in a large pediatric population with long-term fol- low-up. Differences between pediatric and adult patients include rapid growth spurts and a changing metabolic and hor- monal milieu that can alter the functional level of immunosuppression. The pur- pose of this study was to assess the utility and safety of the routine surveillance biopsy in infants and children at least 2 years after transplantation. S TUDY D ESIGN Patient Population Fifty-six pediatric patients at Stanford University were entered in this study during the period from September 1985 to J une 1997. Indications for transplan- tation were dilated cardiomyopathy (n = 39), hypoplastic left heart syndrome (n = 7), hypertrophic cardiomyopathy (n = 2), postoperative complex congenital heart disease with refractory ventricular failure (n = 6), and anomalous origin of the left coronary artery from the pul- S S afety and utility of the routine surveillance biopsy in pediatric patients 2 years after heart transplantation Clifford Chin, MD, Mustansar J. Akhtar, MD, David N. Rosenthal, MD, and Daniel Bernstein, MD Heart transplantation is a well-accepted treatment for end-stage cardiac disease in children. Short- and long-term survival is excellent because of improvement in organ preservation, immunosuppression strategies, and care of the immunosup- pressed individual. Allograft rejection, however, still remains a leading cause of morbidity and mortality after heart trans- plantation. Many attempts have been From the Division of Pediatric Cardiology, Stanford University, Stanford, California. Submitted for publication Nov 23, 1998; revi- sions received Mar 9, 1999, and J uly 7, 1999; accepted Sept 21, 1999. Reprint requests: Clifford Chin, MD, Assis- tant Professor of Pediatrics, Division of Pedi- atric Cardiology, 750 Welch Rd, Suite 305, Palo Alto, CA 94304. Copyright © 2000 by Mosby, Inc. 0022-3476/2000/$12.00 + 0 9/21/103362 G3+ Grade 3-4 rejection ISH LT International Society of H ear t and Lung Transplantation Objectives: The standard for diagnosing allograft rejection after heart transplantation is the endomyocardial biopsy, but the value of routine sur- veillance biopsies after 2 years after transplant is controversial. The objec- tive of this study was to determine the necessity and safety of surveillance biopsies and to correlate rejection with signs and symptoms beyond the sec- ond post-transplant anniversary in pediatric patients. Study design: We reviewed the results of 899 biopsies and coincident clini- cal histories in 56 pediatric patients, comprising 314 patient-years of follow- up. Patients were classified as having symptoms or not based on a blinded review of their clinical status and echocardiograms. Biopsies were classified as negative or positive with established criteria. Results: After biopsies performed less than 2 years after transplant or as a follow-up for a positive biopsy were excluded, 481 biopsies were available for analysis, of which 20 (4%) were positive. Positive biopsies were found in 15 (3%) of 456 biopsies in patients without symptoms compared with 5 (20%) of 25 biopsies in patients with symptoms. Patients with symptoms were 6 times more likely to have a positive biopsy compared with patients without symptoms. Of the positive rejection episodes, 75% occurred in pa- tients without symptoms. Conclusion: Although rejection is uncommon in pediatric patients greater than 2 years after transplant, episodes of treatable allograft rejection can occur in the absence of clinical signs and symptoms. This study emphasizes the safety of and the need to continue to perform routine surveillance biop- sies in patients without symptoms, even after the second post-transplant year. (J Pediatr 2000;136:238-42)