Rhythm control versus rate control in patients with atrial fibrillation and heart failure across the left ventricular ejection fraction spectrum

Background: Rhythm control and rate control are both employed commonly in patients with atrial fibrillation (AF) and heart failure (HF), but limited real-world data exist on them. We aimed to compare outcomes between these two strategies across the left ventricular ejection fraction (LVEF) spectrum. Materials and methods: This retrospective cohort study used data from the randomized MISOAC-AF trial, including from patients with AF and coexistent HF who were hospitalized and followed up after discharge. At baseline, the patients were classified into pharmaceutical (or electrical cardioversion) rhythm control strategy or rate control treatment (b-blocker, digoxin, calcium channel blockers) groups. The primary outcome was all-cause mortality. Kaplan-Meier curves and multivariable-adjusted Cox regression were utilized to compare the two strategies. Spline curve models were used to demonstrate the results across the LVEF stratified spectrum. Results: In total, 199 AF patients with HF were studied (mean age, 77 years). At discharge, 73 (36.7%) patients received rhythm control and 126 (63.3%) rate control treatment. After a median follow-up period of 31 months, 26 (35.6%) patients in the rhythm-control group died, as compared to 43 (33.3%) in the rate-control group (aHR: 1.29; 95% CI: 0.78-2.14; p = 0.31). The spline curves also revealed no difference in all-cause mortality favoring either strategy in any HF subtype across the nominally classified LVEF. Conclusion: The use of a pharmacological rhythm-control strategy was not associated with a survival advantage compared to the rate control strategy in recently hospitalized patients with AF and comorbid HF. More randomized trials and large studies are needed in the future to explore these results in each subgroup of HF patients.