Intermediate outcomes of rheumatic mitral stenosis post-balloon mitral valvotomy.

BACKGROUND: Balloon mitral valvotomy is a standard therapeutic modality for managing rheumatic mitral stenosis. Data on intermediate outcomes of this procedure are limited. Thus we investigated the intermediate outcome after balloon mitral valvotomy performed at a large tertiary center in India.

METHODS: Case records and follow-up data of 2330 patients who underwent valvotomy from June 1999 to December 2005 were retrieved from the hospital information system and analyzed.

RESULTS: The median age of the patients was 32 ± 11 years, 1363 were female including 36 who were pregnant, and 379 were in atrial fibrillation. Follow-up ranged from 1 to 14 years (mean 4.5 years, median 4.0 years). The procedural success rate was 93%. Atrial fibrillation, higher functional class, and worse valve morphology were independent predictors of a poor procedural outcome. Patients with sinus rhythm had better event-free survival (10.43 years, 95% confidence interval: 10.1-10.7) compared to those with atrial fibrillation (8.17 years, 95% confidence interval: 7.5-8.8). Patients who achieved a valve area >1.75 cm(2) had a better event-free survival (11.7 years, 95% confidence interval: 11.4-12.0) than those with a valve area of 1.5-1.74 cm(2) (9.3 years, 95% confidence interval: 9.0-9.7). On multivariate analysis, higher functional class, worse valve morphology, and new significant mitral regurgitation were predictors of a poor outcome. Achieved mitral valve area >1.75 cm(2) was an independent predictor of a good outcome.

CONCLUSION: Patients with sinus rhythm, less gross valve deformity, and a post-balloon mitral valvotomy area >1.75 cm(2) had better intermediate outcomes.