The spectacular clinical success of heart transplantation (HTTX) in the cyclosporine era has engendered challenging new clinical problems that include long-term management of patients with severely compromised systolic function, preparation of potential HTTX recipients for major surgery followed by immunosuppression, and ethical and rational distribution of limited numbers of donated organs. The magnitude of these challenges may seem overwhelming. Fortunately, clinicians have the luxury of dealing with the issues involved one patient, and one step, at a time. The continued efforts of clinical investigators have clarified important management principles. There is a growing appreciation of the pivotal importance of mitral valve function in determining the response to medical therapy and long-term prognosis in this patient population. Enthusiasm for pharmacologic control of asymptomatic ventricular ectopy has waned; instead, the restoration and maintenance of normal atrial function has clearly taken precedence. In preparation for surgery, new endoscopic techniques offer great advantages. The use of high-technology support devices as "bridges to transplantation" has been re-examined in view of the relatively poorer short- and long-term prognosis of patients managed with these devices. Increasingly, the optimal scenario for HTTX entails transplantation of a severely compromised but medically stable patient. As specific therapy, HTTX today has relatively limited application to the vast majority of patients with heart failure (HF). Seventeen hundred heart transplants will do little to directly affect the 400,000 patients in the United States who each year develop symptomatic HF.(ABSTRACT TRUNCATED AT 250 WORDS)