Immediate and late clinical outcomes of balloon mitral valvotomy based on immediate postballoon mitral valvotomy mitral valve area & percentage gain in mitral valve area—A tertiary centre study

The aim of the study was to compare the immediate and late clinical outcomes of balloon mitral valvotomy (BMV), based on the immediate post-BMV valve area and percentage gain in mitral valve area (MVA). Clinical data of 818 consecutive patients who underwent BMV in our institute from 2000 to 2008 were analyzed retrospectively. They were categorized into three groups based on the postprocedural MVA and percentage gain in valve area—(1) 50% gain with final MVA <1.5 cm2, group 1 (fair result); (2) final MVA of ≥1.5 cm2, group 2 (good result); and (3) <50% gain with final MVA <1.5 cm2, group 3 (suboptimal result). The baseline characteristics of the three patient groups were clearly distinct. Those who had <50% gain with final MVA <1.5 cm2 were older and had higher incidence of atrial fibrillation (17 [22.4%]), heart failure (32 [42.1%]), pulmonary artery hypertension (45 [59.2%]), and significantly deformed valves (39 [51.3%]) at baseline. At a mean follow-up period of 5.64 ± 3.84 years, incidence of redo BMV (23 [4.6%]) and mitral valve replacement (17 [3.4%]) was higher in them than those with immediate MVA ≥1.5 cm2. Among those with MVA <1.5 cm2, events on follow-up were similar irrespective of the percentage gain in MVA. Immediate postprocedural MVA of ≥1.5 cm2, and not percentage gain, predicts better long-term clinical outcomes after BMV. Patients who had less than 50% gain with final MVA <1.5 cm2 represent high-risk population with advanced mitral valve disease and comorbidities.