To determine the prognostic significance of asymptomatic left ventricular (LV) dilatation and LV systolic dysfunction, 1,493 men who were free of symptomatic cardiovascular disease underwent M-mode echocardiography and were then followed for a mean of 4.15 years. At baseline examination, 170 men (11.4%) had an abnormally high end-diastolic LV internal dimension (> or = 56 mm) and 76 (5.1%) had an abnormally low fractional shortening (< or = 30%). During the follow-up period, 68 men experienced 92 cardiovascular disease events. After adjusting for age and traditional cardiovascular disease risk factors in proportional-hazards analyses, fractional shortening was a significant independent predictor of cardiovascular risk (relative risk [RR] = 1.42, 95% confidence interval [CI] 1.12 to 1.81, for decrease of fractional shortening by 4%). Increased risk was also associated with combinations of low fractional shortening and high end-diastolic internal dimension (RR = 3.77, 95% CI 1.59 to 8.93) and with low percent fractional shortening with LV hypertrophy (RR = 5.93, 95% CI 1.97 to 17.85). In conclusion, subclinical LV dilatation and LV systolic dysfunction, although uncommon in men free of overt cardiovascular disease, are associated with increased risk for new cardiovascular disease events.