Cross sectional echocardiography identified vegetations in 45 of 62 (73%) patients who had clinical evidence of active infective endocarditis. The sensitivity of this technique in diagnosing vegetations in infective endocarditis was 93% and the specificity 89%. The predictive value of a positive test was 96% and that of a negative test 80%. Vegetations were detected with a similar frequency on the aortic and mitral valves. The incidence of valvar incompetence, congestive heart failure, and the need for surgical intervention was similar in the patients with and without vegetations. Embolism occurred in 47% of those patients with vegetations and in 12% of those without. The mortality rate was 27% in those with vegetations, and no patient without vegetations died. Thus cross sectional echocardiography is accurate in diagnosing vegetations in patients with infective endocarditis, and this finding identifies patients at high risk of embolic complications and death.