From June 1987 to October 1991, 12 patients with congenital mitral valve stenosis underwent surgical correction. Their ages ranged from 2 to 74 months. Nine patients were less than 22 months of age. Five patients were in New York Heart Association functional class IV, and seven patients were in class III. In nine, parachute-type mitral stenosis was clearly definite. In three, a complex congenital valvular and subvalvular stenosis was found. Associated anomalies were present in every patient; five had undergone previous operations. Correction of the mitral stenosis was done through an apical left ventriculotomy. The removal of the mitral obstruction starts from below; the papillary muscle was split and the chordae were divided or fenestrated. The commissurotomies were performed from the ventricular aspect of the mitral valve. Associated anomalies were corrected simultaneously. The operative mortality rate was zero. There was one late death, which was unrelated to cardiovascular status. The echocardiographic serial postoperative studies (up to 52 months) showed no significant residual mitral stenosis and normal global and regional function of the left ventricle in all but one patient.