Isolated cleft of the mitral valve: distinctive features and surgical management.

Background Controversy remains as to whether isolated cleft of the mitral valve and cleft of the atrioventricular septal defect are different entities. Our objectives were to provide a precise description of isolated cleft of the mitral valve and to clarify its surgical management and outcome. Methods Patients with surgical repair of isolated cleft of the mitral valve were included. Results Ten patients (9 female) underwent repair at a mean age of 12.1 ± 10.5 years and mean weight of 32.1 ± 17.8 kg. Preoperative echocardiography showed mild or less than mild mitral regurgitation in 6 cases and moderate to severe regurgitation in 4. Intraoperative examination confirmed in all cases a cleft dividing the anterior leaflet of an otherwise normal mitral valve. Attachment of the cleft to the ventricular septum by accessory chordae was found in 3 cases whereas preoperative echocardiography found such attachments in 5. Direct suture of the cleft was performed in 9 cases, associated with repair of tricuspid valve straddling (n = 1), subaortic stenosis (n = 1), and ventricular septal defect (n = 1). One patient with thickened cleft's edges required an Alfieri-type repair. After a mean follow-up of 4.9 years (range, 1.3 to 11.9), all patients are asymptomatic without significant mitral regurgitation. Conclusions Echocardiographic description of isolated cleft of the mitral valve is not always as accurate as intraoperative analysis. This is a distinct morphologic entity from the cleft of the left-sided valve of atrioventricular septal defect, and seems associated with a strong female predominance, with various cardiac and extracardiac features. Surgical repair is successful with excellent midterm results.