M-mode echo recordings of the left ventricle and left ventricular inflow Doppler velocimetry were performed in 34 male alcoholics below age 45 and in 25 nonalcoholic male controls. Groups were well matched for age, body surface area and heart rate. Systolic arterial pressure was slightly higher in alcoholics and none of the subjects studied had cardiorespiratory symptoms. Data from imaging echocardiography (M-mode echo) were comparable in both groups, and fractional shortening, reflecting left ventricular systolic performance, was identical. Left ventricular inflow Doppler velocimetry showed quite different results in alcoholics and control subjects for the early diastolic flow velocity peak (0.52 +/- 0.12 versus 0.61 +/- 0.11 m/s; p less than 0.01) and in peak flow velocities in the atrial contraction phase (0.32 +/- 0.11 versus 0.27 +/- 0.06 m/s; p less than 0.05). The lower ratio of both velocities in patients (1.88 +/- 0.95 versus 2.34 +/- 0.60 m/s; p less than 0.05) suggests that left ventricular distensibility is altered in alcoholics. In addition, isovolumetric relaxation period, reflecting an early diastolic event, was slightly but significantly prolonged in alcoholic subjects (68 +/- 14 versus 56 +/- 10 ms; p less than 0.001). It is concluded that diastolic performance is altered in young alcoholics without cardiorespiratory symptoms showing normal systolic performance, and that these alterations may be an early marker of alcoholic cardiomyopathy.