# Incidence and predictors of adverse outcomes in patients with rheumatic mitral stenosis following percutaneous balloon mitral valvuloplasty: a study from a tertiary center in Thailand

## TL;DR

This study finds that about 2% of patients with rheumatic mitral stenosis experience adverse outcomes each year after balloon valvuloplasty, with age and heart conditions as key risk factors.

## Contribution

The study identifies novel predictors of adverse outcomes after PBMV in a Thai population with rheumatic mitral stenosis.

## Key findings

- 19.5% of patients experienced adverse outcomes during a median 5.9-year follow-up.
- Age, tricuspid regurgitation, and post-PBMV valve area and regurgitation were independent predictors of adverse outcomes.

## Abstract

Rheumatic mitral stenosis (MS) remains a common and concerning health problem in Asia. Percutaneous balloon mitral valvuloplasty (PBMV) is the standard treatment for patients with symptomatic severe MS and favorable valve morphology. However, studies on the incidence and predictors of adverse cardiac outcomes following PBMV in Asia have been limited. This study aims to evaluate the incidence and predictors of adverse outcomes in patients with rheumatic MS following PBMV.

A retrospective cohort study was conducted on patients with symptomatic severe MS who underwent successful PBMV between 2002 and 2020 at a tertiary academic institute in Thailand. Patients were followed up to assess adverse outcomes, defined as a composite of cardiac death, heart failure hospitalization, repeat PBMV, or mitral valve surgery. Univariable and multivariable analyses were performed to identify predictors of adverse outcomes. A p-value of < 0.05 was considered statistically significant.

A total of 379 patients were included in the study (mean age 43 ± 11 years, 80% female). During a median follow-up of 5.9 years (IQR 1.7–11.7), 74 patients (19.5%) experienced adverse outcomes, with an annualized event rate of 2.7%. Multivariable analysis showed that age (hazard ratio [HR] 1.03, 95% confidence interval [CI] 1.008–1.05, p = 0.006), significant tricuspid regurgitation (HR 2.17, 95% CI 1.33–3.56, p = 0.002), immediate post-PBMV mitral valve area (HR 0.39, 95% CI 0.25–0.64, p = 0.01), and immediate post-PBMV mitral regurgitation (HR 1.91, 95% CI 1.18–3.07, p = 0.008) were independent predictors of adverse outcomes.

In patients with symptomatic severe rheumatic MS, the incidence of adverse outcomes following PBMV was 2.7% per year. Age, significant tricuspid regurgitation, immediate post-PBMV mitral valve area, and immediate post-PBMV mitral regurgitation were identified as independent predictors of these adverse outcomes.