Functional mitral stenosis resulting from a large mitral valve prosthesis vegetation.

Obstruction of a prosthetic valve by an infective vegetation is a rare and life-threatening complication of endocarditis that demands emergent surgical intervention. In our patient's case, transthoracic echocardiography showed the large vegetation, transthoracic Doppler imaging showed severe obstruction of diastolic flow through the bioprosthetic valve, and transesophageal echocardiography showed that no perivalvular abscess was present. Rapid diagnosis of prosthetic valve infection and obstruction demanded application of all three major echocardiographic modalities and proved critical to the patient's recovery.