Images in cardiovascular medicine. Acute mitral regurgitation due to a torn porcine bioprosthetic cusp.

A46-year-old man presented with a 48-hour history of fevers, sweats, and dyspnea. He had bacterial endocarditis of the native mitral valve 12 years earlier with subsequent mitral valve replacement (MVR) with a Hancock II porcine valve (Medtronic Inc). Examination revealed a Grade 3/6 holosystolic murmur at the apex radiating into the axilla with crackles heard halfway up both lung fields. A diagnosis of infective endocarditis with acute mitral regurgitation (MR) was made and serial blood cultures drawn. Transesophageal echocardiogram (TEE) revealed severe MR (Figure 1). The MR was transvalvular with no perivalvular leak.1–3 A large mobile linear echodense mass (length 2.0 cm) was seen in the left ventricle and this prolapsed across the valve into the left atrium (LA, Figure 2 through 4) along with partial prolapse of one of the leaflets of the valve (Figure 3 and 4). The patient underwent urgent mitral valve replacement where the tissue bioprosthesis was replaced with a 29-mm St Jude Medical bileaflet mechanical valve (St Jude Medical Inc). The left atrium was closed with a patch. Postoperatively, the patient developed complete heart block and required a permanent pacemaker. Blood and tissue cultures were sterile.