Acute mitral regurgitation due to leaflet tear after balloon valvotomy.

Percutaneous mitral balloon valvotomy (PMV) has evolved into an effective method for the treatment of patients with symptomatic mitral stenosis. An increase in mitral regurgitation can occur in '45% of patients undergoing PMV. Severe mitral regurgitation can be caused by rupture of chordae or of a papillary muscle. Noncommissural tearing of the mitral leaflet is also an important mechanism of severe regurgitation after PMV. A 35-year-old woman presented with exertional dyspnea that had been present for 3 months. Physical examination revealed a chronically ill-looking appearance with malar flush and accentuated first heart sound, opening snap, and diastolic rumble at the apex. The ECG revealed normal sinus rhythm with left atrial enlargement. Transthoracic echocardiography revealed severe mitral stenosis with trivial mitral regurgitation. The echo score according to Wilkins et al was '8 (mobility, 2; thickening, 2; subvalvular, 2; and calcification, 2). Balloon mitral valvotomy was performed with a 28-mm Inoue balloon catheter. The effective balloon dilating area was '6.52 m. After 1 dilatation, the patient complained of chest tightness and dyspnea, with a markedly elevated v wave in the left atrial pressure tracing. Transesophageal echocardiography revealed severe eccentric mitral regurgitation toward the anterior wall of the left atrium, with suspicious tearing of the posterior mitral leaflet. These findings were confirmed at subsequent mitral valve replacement surgery with a prosthetic valve. The patient subsequently recovered and was uneventfully discharged days later.