Determinants of decrease in pulmonary hypertension following percutaneous transvenous mitral commissurotomy.

OBJECTIVE: To identify the determinants of decrease in pulmonary hypertension after percutaneous balloon mitral commissurotomy. STUDY DESIGN: Quasi experimental study. PLACE AND DURATION OF STUDY: National Institute of Cardiovascular Diseases, Karachi, from March to October 2007. METHODOLOGY: Adult patients with severe mitral stenosis and pliable valve having no significant mitral regurgitation, aortic valve disease, or left atrial thrombus were selected for Percutaneous Transvenous Mitral Commissurotomy (PTMC) by double balloon method. All patients underwent echocardiography of left and right heart catheterization before and after PTMC. Univariate and multivariate analysis was done to assess the relation of age, gender, left atrial size, right ventricular size, gradient across mitral valve, valve area, valve area per meter, 2 body surface area, and presence of Tricuspid Regurgitation (TR) on the decrease in pulmonary arterial pressure. RESULTS: Of the 100 cases included in the final analysis, 60% were female, 84% were in sinus rhythm and had a mean age of 27 years. There was a 48% decrease in mean left atrial and 29% decrease in right ventricular systolic pressure immediately postprocedure. The mitral valve area increased from 0.883 +/- 0.1261 cm(2), pre-ballooning to 1.7864+/-0.28445 cm(2) post-PTMC, a percent change of 102.41%. In multivariate analysis, mean left atrial pressure (p=0.00: CI=0.317 - 0.007), younger age (p=0.010: CI=-0.667 to -0.095) and right ventricular size (p=0.038: CI: 0.25-0.871) were independent predictors of decrease in systolic pulmonary arterial pressure post-PTMC. CONCLUSION: Younger age, mean and left atrial pressure and right ventricular size were independent predictors of decrease in pulmonary systolic pressure immediately post-PTMC.