The vegetation that was not a vegetation: excusable misinterpretation of transesophageal echocardiography findings in late infective endocarditis of a prosthetic mitral valve.

The echocardiographic detection of a valvar mobile mass with independent mobility is one of the major Duke criteria for diagnosing infective endocarditis.(1) We report a case in which a mobile mass seen by transesophageal echocardiography on a prosthetic mitral valve with proven endocarditis was not a vegetation but pannus. This is an important clinical message for the interpretation of mobile masses on artificial valves.