Mitral Regurgitation after Percutaneous Balloon Mitral Valvotomy in Patients with Rheumatic Mitral Stenosis: A Single-Center Study

BACKGROUND: Percutaneous balloon mitral valvotomy (BMV) is the gold standard treatment for rheumatic mitral stenosis (MS) in that it causes significant changes in mitral valve area (MVA) and improves leaflet mobility. Development of or increase in mitral regurgitation (MR) is common after BMV. This study evaluated MR severity and its changes after BMV in Iranian patients. METHODS: We prospectively evaluated consecutive patients with severe rheumatic MS undergoing BMV using the Inoue balloon technique between February 2010 and January 2013 in Madani Heart Center, Tabriz, Iran. New York Heart Association (NYHA) functional class and echocardiographic and catheterization data, including MVA, mitral valve mean and peak gradient (MVPG and MVMG), left atrial (LA) pressure, pulmonary artery systolic pressure (PAPs), and MR severity before and after BMV, were evaluated. RESULTS: Totally, 105 patients (80% female) at a mean age of 45.81 ± 13.37 years were enrolled. NYHA class was significantly improved after BMV: 55.2% of the patients were in NYHA functional class III before BMV compared to 36.2% after the procedure (p value < 0.001). MVA significantly increased (mean area = 0.64 ± 0.29 cm(2) before BMV vs. 1.90 ± 0.22 cm(2) after BMV; p value < 0.001) and PAPs, LA pressure, MVPG, and MVMG significantly decreased. MR severity did not change in 82 (78.1%) patients, but it increased in 18 (17.1%) and decreased in 5 (4.8%) patients. Patients with increased MR had a significantly higher calcification score (2.03 ± 0.53 vs.1.50 ± 0.51; p value < 0.001) and lower MVA before BMV (0.81 ± 0.23 vs.0.94 ± 0.18; p value = 0.010). There were no major complications. CONCLUSION: In our study, BMV had excellent immediate hemodynamic and clinical results inasmuch as MR severity increased only in some patients and, interestingly, decreased in a few. Our results, underscore BMV efficacy in severe MS. The echocardiographic calcification score was useful for identifying patients likely to have MR development or MR increase after BMV.