From 1976 to 1986, six cases of cardiac sarcoidosis have been documented by myocardial biopsy in three of five instances; on examination of the explanted heart after transplantation in two, and at autopsy in one patient. Right ventricular end-diastolic pressure was elevated in all four patients with right ventricular involvement with sarcoidosis. Of three patients treated with steroids, improvement in ventricular function and decrease in arrhythmia occurred in two, whereas failure to respond led to transplantation in the other patient. Two further patients have undergone heart transplantation, one for resistant ventricular arrhythmia and the other for congestive heart failure. No recurrence of sarcoidosis has occurred in the grafts. Because two of five patients had sarcoidosis diagnosed on gross examination, a negative endomyocardial biopsy does not exclude the diagnosis of myocardial sarcoidosis, which should therefore be pursued in the setting of unexplained heart failure, conduction abnormalities, and ventricular arrhythmia, particularly when right ventricular end-diastolic pressure is raised. Steroids may result in improvement in some patients even in the presence of severe morphological damage. Heart transplantation may be performed without increased risk of recurrence of sarcoidosis.