Open mitral commissurotomy: long-term results with echocardiographic correlation.

Over 11 years, 91 patients with isolated mitral stenosis underwent open mitral commissurotomy. Twenty-nine were 50 or more years old; 15 had had prior commissurotomies. Four (4.4%) died perioperatively; 87 were followed for one to nine years (average: five years). Overall actuarial survival was 94% at 5 years. Sixty-nine patients (79%) were NYHA Functional Class (FC) I or II at latest follow-up. Arterial embolism occurred in five patients; 14 patients (16%) had a second valve operation. Patients who remain in FC I or II and who are free of embolism and reoperation are classified as complication-free. Actuarial analysis demonstrated 76% to be so classified at five years after operation. Actuarial curves show that age older than 40 years, sex, previous commissurotomy, and "radical" versus simple open mitral commissurotomy did not influence survival or the incidence of good results. Follow-up M-mode and 2D echocardiograms were obtained in 42 patients. The estimated mitral orifice accurately separated FC I patients (orifice equal to or larger than 2 cm2) from FC II and FC III patients (orifice smaller than 2 cm2), and showed that echocardiographic evidence of a 2 cm2 or larger mitral orifice correlates with a good result.