Late results of percutaneous mitral commissurotomy in a series of 1024 patients. Analysis of late clinical deterioration: frequency, anatomic findings, and predictive factors.

BACKGROUND The optimal use of percutaneous mitral commissurotomy (PMC) in a wide range of patients requires accurate evaluation of late results and identification of their predictors. METHODS AND RESULTS Late results of PMC were assessed in 1024 patients whose mean age was 49+/-14 years. Echocardiography showed that 141 patients (14%) had pliable valves and mild subvalvular disease, 569 (55%) had extensive subvalvular disease, and 314 (31%) had calcified valves. A single balloon was used in 26 patients, a double balloon in 390, and the Inoue Balloon in 608. Good immediate results were defined as valve area >/=1.5 cm2 without regurgitation >2/4 (Sellers' grade) and were obtained in 912 patients. Median duration of follow-up was 49 months. The 10-year actuarial rate of good functional results (survival with no cardiovascular death and no need for surgery or repeat dilatation and in New York Heart Association [NYHA] class I or II) was 56+/-4% in the entire population. Follow-up echocardiography was available in 90% of the patients who experienced poor functional results after good immediate results and showed restenosis in 97% of these. In multivariate analysis, the predictors of poor functional results were old age (P=0.0008), unfavorable valve anatomy (P=0.003), high NYHA class (P<0.0001), atrial fibrillation (P<0.0001), low valve area after PMC (P=0.001), high gradient after PMC (P<0.0001), and grade 2 mitral regurgitation after PMC (P=0.04). CONCLUSIONS PMC can be performed with good late results in a variety of patient subsets. Prediction of late events is multifactorial. Knowledge of these predictors can improve patient selection and follow-up.