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.