Predictors of clinical events or restenosis during follow-up after percutaneous mitral balloon valvotomy

Abstract

Aims. The purpose of this study is to define predictors of events or restenosis during follow-up after percutaneous mitral balloon valvotomy. Methods and Results. Percutaneous mitral balloon valvotomy was attempted in 137 patients with severe mitral valve stenosis. In 127 patients follow-up was complete with a mean of 4.2 ± 2.6 years. Events during follow-up were defined as death, mitral valve surgery or repeat percutaneous mitral balloon valvotomy. Restenosis was defined as a decrease in mitral valve area from ≥ 1.5 cm2 following percutaneous mitral balloon valvotomy to < 1.5 cm2. There was 80 ± 4% event-free survival 4 years after percutaneous mitral balloon valvotomy. Multivariate analysis showed chronic atrial fibrillation at baseline (P = 0.39, relative risk (RR) = 2.5) and a high residual maximal gradient after percutaneous mitral balloon valvotomy (P = 0.004, RR = 2.0 per 5 mmHg) to be independent predictors of an event during follow-up. The restenosis rate was 28.3% after 4 years. Chronic atrial fibrillation at baseline (P = 0.0338, RR = 2.2), a small mitral valve area after percutaneous mitral balloon valvotomy (P = 0.0003, RR = 0.8/0.1 cm2) and a high residual maximal transmitral gradient (P = 0.0252. RR = 1.6/5 mmHg) were all independent predictors of restenosis. Conclusion. Patients with chronic atrial fibrillation and a high maximal transmitral gradient after percutaneous mitral balloon valvotomy have a higher risk for events during follow-up. Restenosis is related to the presence of chronic atrial fibrillation at baseline and a suboptimal percutaneous mitral balloon valvotomy result.