Mitral Valve Strands in Patients With Focal Cerebral Ischemia

BACKGROUND AND PURPOSE: Filamentous strands attached to the mitral valve are a recently described finding in occasional patients undergoing transesophageal echocardiography (TEE), but the frequency and clinical significance of these strands remain poorly defined. The purpose of the present study was to review the prevalence of mitral valve strands in patients undergoing TEE examination and to explore the relation of these strands to cardioembolic cerebral ischemia. METHODS: All patients with native mitral valves referred for clinically indicated TEE over a 2-year period at our institution were evaluated for the presence of mitral valve strands (defined as highly mobile filamentous masses <1 mm thick attached to the atrial surface of mitral leaflets). RESULTS: Of 968 study patients, mitral valve strands were identified in 22 individuals (2.3%). Mitral valve strands were significantly more common in patients referred for TEE as a result of a recent ischemic cerebrovascular event compared with patients referred for other study indications (6.3% versus 0.3%, respectively; P<.00001). Among patients < or = 50 years of age with likely cardioembolic stroke or transient ischemic attack, 16% were found to have mitral valve strands on TEE examination. In 9% of these young patients, no other TEE finding associated with cardioembolic risk was present. CONCLUSIONS: Filamentous strands attached to the mitral valve appear to represent another risk factor for embolic cerebral ischemia, particularly in patients < or = 50 years of age.