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Closed mitral valvulotomy after the age of fifty.

This retrospective study is based upon a consecutive series of 90 patients with mitral stenosis who had their first closed mitral valvulotomy after the age of fifty. All patients were operated on during the period 1959--70 and were followed-up for at least 5 years until July 1, 1976. Calculated survival curves were compared with those of a group of 68 patients over fifty whose mitral stenosis was medically treated. The surgical mortality was 7.8%, largely due to the high mortality among patients in functional class IV. The late mortality rate after valvulotomy was significantly higher than in a matched population of the same age and sex, but significantly lower than in the medically treated patients. According to functional classification, the patients had improved markedly at the time of follow-up. High incidences of atrial fibrillation and late thromboembolic complications were noted. This study supports the view that closed mitral valvulotomy can be performed safely in patients over fifty with mitral stenosis without significant mitral regurgitation and heavy clacifications in functional classes II and III.