Comparative Effectiveness of Early Rhythm Control Versus Rate Control for Cardiovascular Outcomes in Patients With Atrial Fibrillation.

Background Rhythm control is associated with better cardiovascular outcomes than usual care among patients with recently diagnosed atrial fibrillation (AF). This study investigated the effects of rhythm control compared with rate control on the incidence of stroke, heart failure, myocardial infarction, and cardiovascular death stratified by timing of treatment initiation. Methods and Results We conducted a retrospective population-based cohort study including 22 635 patients with AF newly treated with rhythm control (antiarrhythmic drugs or ablation) or rate control in 2011 to 2015 from the Korean National Health Insurance Service database. Propensity overlap weighting was used. Compared with rate control, rhythm control initiated within 1 year of AF diagnosis decreased the risk of stroke. The point estimates for rhythm control initiated at selected time points after AF diagnosis are as follows: 6 months (hazard ratio [HR], 0.76; 95% CI, 0.66-0.87), 1 year (HR, 0.78; 95% CI, 0.66-0.93), and 5 years (HR, 1.00; 95% CI, 0.45-2.24). The initiation of rhythm control within 6 months of AF diagnosis reduced the risk of hospitalization for heart failure: 6 months (HR, 0.84; 95% CI, 0.74-0.95), 1 year (HR, 0.96; 95% CI, 0.82-1.13), and 5 years (HR, 2.88; 95% CI, 1.34-6.17). The risks of myocardial infarction and cardiovascular death did not differ between rhythm and rate control regardless of treatment timing. Conclusions Early initiation of rhythm control was associated with a lower risk of stroke and heart failure-related admission than rate control in patients with recently diagnosed AF. The effects were attenuated as initiating the rhythm control treatment later.