Fifty patients with primary myocardial disease have been followed up for a mean period of 2½ years following their initial episode of congestive heart failure. Once heart failure occurred, myocardial disease has been persistent. Excess alcohol intake was common but not universal, and its precise role in the pathogenesis of this syndrome remains uncertain; it does not appear to be a major influence on the clinical features or course of patients in this study. Return of the heart size to normal has generally not resulted in maintenance of normal size and has not beneficially influenced the prognosis. Persistent premature ventricular contractions proved to be a bad prognostic sign.