Long-term surgical outcome of closed mitral commissurotomy.

Seven hundred and fifty-four patients who underwent closed mitral commissurotomy (CMC) between 1958 and 1993 (71% female, 29% male; mean age 39 years) for acquired mitral stenosis were reviewed postoperatively. Particular attention was given to those patients who later required mitral valve replacement (MVR). The total follow up experience was 9,607.9 years. Eighty-two patients (11%) needed a repeat CMC and 30% of these patients had subsequent MVR. In all, 146 patients (19, 3%) required MVR a mean of 17.0 years after commissurotomy (range one to 35 years). Preoperative factors associated with an unsatisfactory postoperative course and with later MVR included preoperative functional class, calcification of the mitral valve and subvalvular fusion. The adequacy of valvulotomy assessed at operation was also related to outcome. Postoperatively, poor functional improvement, congestive heart failure and the necessity for a repeat CMC were associated with late MVR. The indications for MVR were restenosis (59%), residual stenosis with or without mild mitral regurgitation (30%), and moderate to severe regurgitation (11%). Among survivors, 88% improved at least one functional class after MVR and the majority was free of congestive heart failure. It is concluded that CMC provides excellent long term clinical improvement in appropriately selected patients. The mean time interval of 17 years between CMC and late MVR reveals the efficacy of CMC to achieve satisfactory long term results.