Cross-sectional and M-mode echocardiograms were performed on 23 consecutive patients with infective endocarditis. Both M-mode and cross-sectional echocardiography identified vegetations in 18 patients, 10 of whom required valve replacement within 1 month of presentation. Cross-sectional echocardiography alone identified a vegetation in one patient with a prosthetic valve. Neither technique identified vegetations in five instances. The size and shape of a vegetation on cross-sectional echocardiography did not accurately predict the need for early valve replacement or the incidence of major peripheral emboli.