Percutaneous transvenous mitral commissurotomy: significance of echocardiographic assessment in prediction of immediate result.

BACKGROUND The current study aims to identify demographic, clinical characteristics, echocardiographic and/or mitral valve morphological parameters that may predict the successful result of percutaneous transvenous mitral commissurotomy (PTMC).  METHODS The medical records of 196 patients (48 males, mean age: 42.7 ± 11.5 years) who underwent PTMC were reviewed. Prior to PTMC, a combination of transthoracic and transesophageal echocardiography were used to investigate substantial mitral valve morphological subcomponents (thickening, mobility, calcification, and subvalvular thickness) and suitability for PTMC. The second transthoracic echocardiographic assessment was performed within six weeks after PTMC. Patients were divided into two categories of successful or unsuccessful according to PTMC results. Successful PTMC was defined as: final mitral valve area (MVA) ≥1.5 cm2 without a post-procedure mitral regurgitation (MR) grade >2. The significant predictor of the result was identified by comparing demographic data, initial echocardiographic assessments and mitral valve morphological scores within both groups.  RESULTS The mean MVA increased from 1.0 ± 0.2 cm2 to 1.7 ± 0.4 cm2, and mitral valve mean gradient (MVMG) decreased from 11.5 ± 5.2 to 5.2 ± 3.3 mmHg (P < 0.001 for both). Successful results were obtained in 139 (70.9%) patients compared to unsuccessful results in 57 (29.1%). Unsuccessful results were due to suboptimal secondary MVA < 1.5 cm2 in 50 (25.5%) patients and post-procedure MR grade >2 in 7 (3.6%). Multiple logistic regression analysis indicated that young age, lower size of the left atrium (LA), and smaller degree of mitral valve thickness were the predictors of successful result.  CONCLUSION Pre-procedure echocardiographic assessment appears to be helpful in predicting PTMC results. Successful PTMC is influenced by the patients' age, LA size, and mitral valve thickness.