In July 1983, a heart transplant program was initiated. Up to September 1985, 72 orthotopic transplants in 69 patients (62 men, 7 women, age 9 to 55 years, mean 40.1 years) have been performed. All patients suffered from end-stage heart failure, which was due to coronary artery disease in 15 patients, congestive cardiomyopathy in 53 patients and endocardial fibrosis in one woman. All patients survived the operation, but there were 6 deaths within the first 30 postoperative days. Eight more patients died subsequently. Causes of death were rejection in 6, infection in 3, cerebral hemorrhage in 2, sudden death in 2 and pulmonary embolism in one patient. Actuarial survival at one and two years was calculated at 75%. The detection of allograft rejection was the major postoperative problem. This was achieved by serial endomyocardial biopsy and myocardial voltage monitoring via a telemetry pacemaker system. The lowest rate of organ toxicity, rejection and infection was achieved using a triple immunosuppressive regime including Azathioprine, Cyclosporine A and steroids with initial doses of antithymocyte globulin. It is concluded that heart transplantation can be regarded as a routine procedure for patients with intractable heart failure. The operative risk is limited, and an elaborate immunosuppressive regimen makes long-term survival possible without obvious allograft deterioration. Cardiac transplantation should be seriously considered in patients under 55 years, who suffer from life-threatening heart failure not amenable to other modes of therapy.