The aim of this study was to correlate the findings obtained by transesophageal echocardiography (TEE) with those obtained during surgery and histopathologic studies in patients with mitral and/or aortic infective endocarditis. Twenty eight patients were studied. In all of them clinical history, bacteriological study and TEE. In 15 cases a positive blood culture was found and in 13 the blood culture was negative. The TEE demonstrate infective aortic vegetations in 12 cases, in mitral valve in 11 and in five in both valves. The endocarditis-associated complications were found in 53% of cases and the incidence of embolic events was of 25%. TEE findings related with the presence of vegetations were confirmed in the studies of pathologic anatomy in 92.8% and at surgery in 89.2%. These data suggest that the TEE leads to a significant improvement in the diagnosis and prognosis of mitral and/or aortic infective endocarditis, because it has a high correlation with the studies of pathologic anatomy and surgery.