Relationship between valve calcifcation and long-term results of percutaneous mitral commissurotomy for rheumatic mitral stenosis

Abstract

Background-Indications of percutaneous mitral commissurotomy (PMC) remain debated in calcifc mitral stenosis. We analyzed long-term results of PMC for calcifc mitral stenosis and the factors associated with late functional results. Methods and Results-We compared the characteristics and outcome of 314 patients undergoing PMC for calcifc mitral stenosis with 710 patients with noncalcifed valves followed up to 20 years. Calcifcation was defned by fuoroscopy, and its extent was graded from 1 to 4. Good immediate results (valve area ≥1.5 cm2 with mitral regurgitation ≤2/4) were obtained in 251 patients (80%) with calcifed valves and 661 (93%) with noncalcifed valves (P<0.001). The hazard ratio for good functional results (survival without cardiovascular death, without mitral reintervention, and in New York Heart Association class I or II) was 2.5 (95% confdence interval [2.1-2.9]; P<0.0001) in patients with calcifed valves (12±3% at 20 years) relative to the noncalcifed group (38±2% at 20 years). In the 251 patients with calcifed valves who had good immediate results, 15-year rates of good functional results were 35±4% for minor (grade 1) calcifcation, 24±6% for grade 2, and 10±6% for severe (grades 3-4) calcifcation. Factors associated with poor late functional results on multivariable analysis were calcifcation extent, older age, higher New York Heart Association class, atrial fbrillation, and higher mean gradient after PMC. Conclusions-Although late results of PMC are less satisfying in calcifc mitral stenosis, long-term functional outcome depends on calcifcation extent, patient characteristics, and immediate results of PMC. These fndings support the use of PMC as frst-line treatment in selected patients with calcifc mitral stenosis. © 2014 American Heart Association, Inc.