Effect of catheter ablation on clinical outcomes in patients with atrial fibrillation and significant functional mitral regurgitation

In patients with atrial fibrillation (AF) and functional mitral regurgitation (MR), catheter ablation reduces the severity of MR and improves cardiac remodeling. However, its effects on prognosis are uncertain.

This retrospective study included 151 consecutive patients with AF and functional MR, 82 (54.3%) of whom were treated by catheter ablation (Ablation group) and 69 (45.7%) with drug therapy without ablation (Non-ablation group). Forty-three pairs of these patients were propensity matched on the basis of age, CHA₂DS₂-VASc scores, and left ventricular ejection fraction. The primary outcome evaluated was severity of MR, cardiac remodeling and the combined incidence of subsequent heart failure-related hospitalization and strokes/transient ischemic attacks.

Patients in the Ablation group showed a significant decrease in the severity of MR (p < 0.001), a significant decrease in the left atrial diameter (p = 0.010), and significant improvement in the left ventricular ejection fraction (p = 0.015). However, patients in the Non-ablation group showed only a significant decrease in the severity of MR (p = 0.004). The annual incidence of the studied events was 4.9% in the Ablation group and 16.7% in the Non-ablation group, the incidence being significantly lower in the ablation than Non-ablation group (p = 0.026) according to Kaplan–Meier curve analyses. According to multivariate Cox regression analysis, catheter ablation therapy (hazard ratio [HR] 0.27, 95% confidence interval [CI] 0.09–0.84; p = 0.024) and heart failure at baseline (HR 3.84, 95% CI 1.07–13.74; p = 0.038) were independent predictors of the incidence of the studied events.

Among patients with AF and functional MR, catheter ablation was associated with a significantly lower combined risk of heart failure-related hospitalization and stroke than in a matched cohort of patients receiving drug therapy alone.