Association Between Catheter Ablation for Nonparoxysmal Atrial Fibrillation and Functional Mitral Regurgitation in Patients With Heart Failure With Preserved Ejection Fraction.

Functional mitral regurgitation (FMR) often coexists with atrial fibrillation (AF) and may have a causal relation with AF persistence and exacerbation of heart failure (HF). The purpose of this study was to investigate the impact of FMR on AF catheter ablation (AFCA) outcomes and improvement in FMR after AFCA in patients with HF with preserved ejection fraction (HFpEF) and nonparoxysmal AF. Excluding patients with primary valve disease or post-mitral valve repair, 280 patients with HFpEF who underwent CA for nonparoxysmal AF were retrospectively included. All patients completed 1-year follow-up and were assessed for FMR, AF recurrence and HF parameters, including echocardiography. At baseline, FMR was present in 153 (54.6%) patients (mild, n = 112; moderate, n = 40; severe, n = 1), and these were decreased to 70 (25%) significantly 1 year after AFCA (mild, n = 64; moderate, n = 6), 119 patients (78%) had improvement in MR (a decrease of ≥1 level in the severity from baseline to 1 year on echocardiography). Overall, 274 patients (97.9%) had sinus rhythm at the 1-year examination, and recurrent AF-free survival did not differ in patients with and without MR improvement (83.2% vs 82.4%, p = 0.908). However, the MR improvement group had a significantly lower cardiothoracic ratio, left atrial diameter, E/e', and B-type natriuretic peptide levels after 1 year than those in the MR nonimprovement group. In conclusion, the majority of the HFpEF patients with nonparoxysmal AF had improvement of FMR after AFCA with the high maintenance of sinus rhythm, leading to a virtuous cycle of cardiac function.