Mitral valve aneurysm formation documented by cross-sectional echocardiography.

We report a case of mitral valve aneurysm secondary to Streptococcus viridans endocarditis of the mitral valve. Cross-sectional echocardiography demonstrated an initial thickening of the anterior mitral leaflet which evolved further into an aneurysm. Surgery showed that this lesion had subsequently perforated. This case highlights the ability of echocardiography to detect gradual anatomic changes in the course of bacterial endocarditis. The diagnosis of such abnormalities might have important therapeutical implications and might lead to a more aggressive surgical approach.