A total of 286 patients with mitral stenosis or predominant mitral stenosis underwent open heart mitral commissurotomy at the San Camillo Hospital between May 1969 and May 1975; mitral annuloplasty was performed on 71 patients, subvalvular apparatus correction on 43. The operative mortality rate was 0,7% (no deaths among the last 220 patients). Early results, evaluated from intraoperative data, clinical course, acoustic and polygraphic postoperative findings, were good in 228 patients (80%), fairly good in 41 (14%), bad in 17 (6%).