Independent Clinical and Echocardiographic Predictors of Restenosis After Percutaneous Mitral Balloon Commissurotomy in a Large, Consecutive Cohort Followed for 24 Years.

OBJECTIVE: To enlighten preprocedural risk factors of mitral valve restenosis in a large, single-center cohort of patients submitted to percutaneous mitral balloon commissurotomy (PMBC) for the treatment of mitral stenosis (MS) secondary to rheumatic heart disease.

METHODS: This is a database analysis of a single-center, high-volume tertiary institution involving all consecutive PMBC procedures performed in the mitral valve (MV). Restenosis was diagnosed when MV area was <1.5 cm² and/or loss of 50% or more of the immediate procedural result aligned with the return/worsened symptoms of heart failure. The primary endpoint was to determine the preprocedural independent predictors of restenosis after PMBC.

RESULTS: Among a total of 1921 PMBC procedures, 1794 consecutive patients without previous intervention were treated between 1987 and 2010. Throughout 24 years of follow-up, MV restenosis was observed in 483 cases (26%). Mean age was 36 years and most (87%) were female. Median follow-up duration was 9.03 years (interquartile range, 0.33-23.38). Restenosis population, however, presented a significantly lower age at the procedure time as well as a higher Wilkins-Block score. At multivariate analysis, independent preprocedure predictors of restenosis were left atrium diameter (hazard risk [HR], 1.03; 95% confidence interval [CI], 1.02-1.05; P<.04), preprocedure maximum gradient (HR, 1.02; 95% CI, 1.00-1.03; P=.04), and higher Wilkins-Block score (>8) (HR, 1.38; 95% CI, 1.14-1.67; P<.01).

CONCLUSIONS: At long-term follow-up, MV restenosis was observed in a quarter of the population undergoing PMBC. Preprocedure echocardiographic findings, including left atrial diameter, maximum MV gradient, and Wilkins-Block score were found to be the only independent predictors.