Open mitral commissurotomy: fourteen- to eighteen-year follow-up clinical study.

From May 1974 to December 1978, 159 patients with mitral stenosis underwent open mitral commissurotomy at our institution. Follow-up data were complete in 96.8%, with a mean follow-up of 13.7 years (range, 14 to 18 years). Preoperatively, most patients (n = 94) were in functional class III or IV. Valve calcification was found in 18 patients (11.3%), left atrial thrombosis was found in 21 (13.2%), and the subvalvular apparatus was affected in 105 (66%). When a residual insufficiency was detected during the operation, a mitral annuloplasty was performed (n = 43). There was one hospital death (0.6%) and 15 late deaths (9.5%). Actuarial survival at 15-year and 18-year follow-up is 89.4% +/- 3% and 75.2% +/- 10.8%. Fifteen patients (9.7%) had a thromboembolic episode 1 to 189 months after operation (mean, 104.3 months). Eleven patients (7%) required reoperation 3 to 183 months after operation (mean, 110.1 months). Freedom from reoperation at 18-year follow-up was 91.9% +/- 2.7%. Event-free actuarial survival at 15-year and 18-year follow-up was 73.4% +/- 4.2% and 54.3% +/- 10.5%. Most patients (n = 131) are in class I or II. Open mitral commissurotomy represents a safe surgical alternative for treating mitral stenosis, allowing a complete removal of atrial thrombosis if present. This long-term follow-up clinical study encourages us to persist in this successful surgical repair of mitral stenosis.