Predictors of systemic embolism in patients with mitral stenosis. A prospective study.

<bold>Background: </bold>Most studies of the predictors of systemic embolism in patients with mitral stenosis have been retrospective.<bold>Objective: </bold>To prospectively study factors associated with systemic embolism in mitral stenosis.<bold>Design: </bold>Prospective cohort study.<bold>Setting: </bold>University-affiliated medical institution with 3000 beds.<bold>Patients: </bold>534 consecutive patients with a mitral valve area of 2.0 cm2 or less; 132 patients were in sinus rhythm, and 402 were in atrial fibrillation.<bold>Measurements: </bold>Nine clinical and 10 echocardiographic variables were assessed for prediction of systemic embolism over a mean (+/- SD) follow-up of 36.9 +/- 22.5 months. Diagnosis of systemic embolism was based on symptoms and signs (sudden onset of peripheral arterial ischemic or neurologic manifestations without prodromes) and on findings on computed tomography, angiography, and surgery.<bold>Results: </bold>For patients in sinus rhythm, age (relative risk [RR], 1.12 [95% CI, 1.04 to 1.21]), the presence of a left atrial thrombus (RR, 37.1 [CI, 2.82 to 487.8]), mitral valve area (RR, 16.9 [CI, 1.53 to 187.0]), and the presence of significant aortic regurgitation (RR, 22.4 [CI, 2.72 to 184.8]) were positively associated with embolism. For patients in atrial fibrillation, previous embolism (RR, 3.11 [CI, 1.66 to 5.85]) was positively associated with embolism; percutaneous balloon mitral commissurotomy (RR, 0.37 [CI, 0.18 to 0.79]) was a negative predictor.<bold>Conclusions: </bold>It may be prudent to give anticoagulants not only to patients in atrial fibrillation and patients with previous systemic embolism but also to those showing a left atrial thrombus or significant aortic regurgitation on echocardiography. Early percutaneous balloon mitral commissurotomy may also help prevent systemic embolism in patients with mitral stenosis. [ABSTRACT FROM AUTHOR]