Preoperative clinical predictors of long term survival in mitral stenosis: analysis of 200 cases followed for up to 27 years after closed mitral valvotomy.

Two hundred patients aged 17-40 years undergoing closed mitral valvotomy during 1955-60 were studied by actuarial survival analysis. The period of follow up was 22-27 years. The following preoperative features were found to be independent predictors of long term survival: sinus rhythm (p less than 0.05); pulmonary arterial pressure below systemic pressure (p less than 0.01); absence of congestive cardiac failure (p less than 0.01) and pure mitral stenosis (p less than 0.01). A better long term survival was found for mitral valvotomy with a Tubb's dilator than finger splitting or Brock's method. The presence of calcification at the time of valvotomy adversely affected survival (p less than 0.01). Anticoagulation improved survival (p less than 0.01). It is concluded that closed mitral valvotomy gives good results if performed before the onset of established atrial fibrillation and congestive cardiac failure and that all patients should have anticoagulation. These results have important implications for selection of patients in countries with limited facilities for open heart surgery.