Pediatric heart transplant recipients were previously reported to have higher early mortality and morbidity than do adult patients treated with triple immunosuppression therapy (steroids, azathioprine and cyclosporine). Nineteen patients (11 infants and 8 older children) underwent orthotopic transplantation using triple immunosuppression therapy. Surveillance for cellular rejection and coronary arteriopathy was performed with endomyocardial biopsy and selective coronary angiography in all patients, with continuous monitoring for hypertension and serious infection. Seventeen of 19 patients (89%; 10 infants and 7 older children) are current survivors, with a median follow-up of 29 months (range 17 to 94). There were 5 and 7 episodes of rejection in the first 12 months after transplantation in the infant and older groups, respectively, for actuarial freedom-from-rejection rates of 65% at 3 months and 54% at 12 months. Severe coronary arteriopathy was detected in 1 infant 11 months after transplantation. In the first 12 months after transplantation, there were 3 hospitalizations for infection, and 2 patients needed treatment for hypertension in the infant group, compared with 1 hospitalization for infection, and 4 patients on antihypertensives in the older group. An increased prevalence of noninfectious complications in the infant group led to significantly longer postoperative stays than in the older group (mean 27.3 vs 19.4 days; p < 0.05). The results indicate that cardiac transplantation using triple immunosuppression therapy in infants, children and adolescents is associated with a high survival rate, and low rates of rejection and serious infection.