The antemortem diagnosis of myocardial sarcoidosis is rare in patients without overt signs of the disease. Two patients are presented to alert physicians to the value of early scalene node biopsy when sarcoidosis could be the cause of marked disturbances in cardiac conduction. The first patient, aged 29 years, had first, second, and third degree atrioventricular block and intermittent left and right bundle-branch block; the second, aged 59 years, had second degree atrioventricular block and complete right bundle-branch block. Both had diagnoses of sarcoidosis based on scalene node biopsy. The cardiac conductive disturbance improved, and the symptoms disappeared with steroid therapy.