To examine effects of chronic alcohol abuse on left ventricular function, 162 otherwise relatively healthy alcohol abusers, having been admitted to a rehabilitation program, underwent cardiac evaluation including chest X-ray, electrocardiogram, and radionuclide angiography after 2 weeks abstinence. Twenty-nine of the 162 alcoholic subjects (18%) with left ventricular dysfunction were identified. Twenty-two had regional wall motion abnormalities, suggesting a localized process, of whom 12 also had depressed ejection fractions. Seven others had a depressed ejection fraction alone with a more global myopathic process. Only 4 of these 29 patients had any history suggesting prior heart disease. Two of the 29 had Q-waves greater than or equal to 0.4 s and 8 had an abnormal cardiothoracic ratio on chest X-ray. Chronic alcohol abusers appear to be at relatively high risk for left ventricular dysfunction; most of which is unrecognized. Routine screening methods failed to identify 85% of our subjects who later were recognized by radionuclide angiography. Since historical and electrocardiographic abnormalities are often absent in this population, detection of left ventricular dysfunction by other methods such as radionuclide angiography must be used.