Acute outcome of percutaneous Inoue-balloon mitral commissurotomy

This study examines the acute results and the potential impact, if any, of 16 clinical, echocardiographic, hemodynamic and balloon-related variables on the acute outcomes of Inoue-balloon percutaneous transvenous mitral commissurotomy (PTMC). Of 107 patients, PTMC was successfully completed in 105 (98%) without cardioembolism or death, and resulted in an increase in mitral valve area from 0.8 +/- 0.2 cm2 to 1.7 +/- 0.4 cm2 (p = 0.0001) as assessed echocardiographically. Optimal results defined as a valve area improvement of > or = 50% and/or a final valve area of > or = 1.5 cm2 without significant mitral regurgitation (> or = 2 grade increase in mitral regurgitation or a final regurgitation > or = 3+) was obtained in 96 patients (91%). Significant mitral regurgitation was observed in six patients. On univariate analysis, patients with suboptimal results were older (52 +/- 7 vs. 44 +/- 10 years, p = 0.037) and were likely to have the procedure performed during the learning phase (first 33 vs.. subsequent 72 patients, p = 0.007) than those with optimal results, and patients with resultant significant mitral regurgitation had more severe pre-existing mitral regurgitation compared with those without (1.4 +/- 0.5 vs. 0.7 +/- 0.7, p = 0.0098). However, there were no independent predictors of either acute outcome identified in multivariate analysis. We therefore conclude that although Inoue-balloon PTMC is a safe and highly effective procedure with a low risk of creating severe mitral regurgitation, the acute outcomes cannot be accurately predicted.