Influence of Rhythm Control on Functional Mitral and Tricuspid Regurgitation Severity and Clinical Outcome in Patients With Atrial Fibrillation: A Propensity-Matched Cohort Study.

Background and objectives: This study evaluated the efficacy of atrial fibrillation (AF) rhythm control therapy in improving functional mitral regurgitation (MR) and tricuspid regurgitation (TR) and its association with clinical outcomes.

Methods: Among 2,574 patients with AF screened from 2003 to 2023, 817 pairs of patients were selected through propensity matching to compare rhythm control therapy (antiarrhythmic drugs, catheter ablation, or electrical cardioversion) with no rhythm control. MR and TR severity were assessed at baseline and follow-up echocardiography conducted at least 3-month intervals. Clinical outcomes included all-cause mortality and heart failure-related hospitalizations.

Results: Rhythm control was associated with a reduction in moderate or greater MR (7.3% to 4.9%, p=0.008) and attenuation of TR progression (9.1% to 9.3%, p=0.796), contrary to the worsening trends in the no rhythm control group. Sinus restoration was more frequent in the rhythm control group compared to the no rhythm control group (60.2% vs. 48.1%, p<0.001). Patients maintaining sinus rhythm after rhythm control showed the greatest MR improvement (7.3% to 3.5%, p=0.002). Rhythm control was also associated with reverse cardiac remodeling, including reductions in left atrial volume index and improved left ventricular ejection fraction (both p<0.001). Clinical outcomes were more favorable in the rhythm control group, particularly among patients with improved regurgitation or restored sinus rhythm.

Conclusions: AF rhythm control therapy is associated with improved functional MR, attenuated TR progression, enhanced sinus rhythm maintenance, and favorable clinical outcomes. Echocardiography can provide valuable information for identifying the optimal timing of rhythm control intervention and assessing treatment response.