Failure of transesophageal echocardiography to visualize a large mitral prosthesis vegetation detected solely by transthoracic echocardiography.

Transesophageal echocardiography yields a highly accurate diagnosis in the detection of valvular vegetations. We describe a case in which omniplane transesophageal echocardiography failed to demonstrate a large vegetation protruding from a Starr-Edwards mitral prosthesis, toward the left ventricular outflow tract. The vegetation could be detected solely by transthoracic echocardiography.