The reliability of echocardiography in the diagnosis of infective endocarditis.

The echocardiograms of 17 patients with proved infective endocarditis were surveyed to assess the reliability of echocardiography in this disease. Vegetations were present on 20 valves (11 aortic, 7 mitral, 2 tricuspid) at surgery or autopsy. Echocardiography correctly identified the abnormality in 11 valves. There were 8 valves with false-negative studies of which only one examination was technically inadequate. One false-positive echocardiogram was found. A negative echocardiogram does not exclude infective endocarditis. The size of the vegetation is not the only consideration in its detection echocardiographically. False-positive and false negative studies are discussed.