Impact of sinus rhythm maintenance using catheter ablation on clinical hard endpoints
A number of large propensity-matched registry-based cohort studies4-8 have shown that catheter ablation of AF is significantly associated with a lower incidence of stroke, heart failure, and death compared with medical therapy alone. However, most of those registry-based studies lacked information on AF recurrence after catheter ablation. The impact of sinus rhythm maintenance after catheter ablation on clinical outcomes has been investigated in only a few retrospective studies and our results were generally in accordance with these previous reports.
Lin et al.20 studied patients with AF whose CHA2DS2-VASc scores were ≥1 and who underwent catheter ablation in Taiwan. In that single-center study, freedom from AF after ablation was found to be a predictor of a lower incidence of major adverse cardiovascular events, including total vascular events (ischemic stroke, TIA, acute coronary artery events, and peripheral vascular events or pulmonary embolism) and death. Unfortunately, the number of study patients was somewhat small (118 in the nonrecurrence group and 56 in the recurrence group).
Hunter et al.21 tested 1273 patients with AF in a multicenter study in the UK and Australia and showed that freedom from AF after ablation was a predictor of stroke free survival. Ghanbari et al.22 studied 3058 patients with AF from a single-center registry in Michigan and found that sinus rhythm maintenance after catheter ablation of AF was independently associated with a lower risk of cardiac mortality, although the authors found no significant reduction in cerebrovascular events or mortality. These two studies are relatively old, and the recruited patients underwent catheter ablation before 2011, thereby predominantly using warfarin instead of DOACs. To identify the effect of sinus rhythm maintenance more clearly, patients taking DOACs might be more suitable than those taking warfarin given that DOACs are associated with fewer adverse events.23-26 All of the patients in our study underwent AF ablation after 2011, and DOACs were predominantly prescribed in 78.4% of the patients. Our study is the first to demonstrate the favorable effect of sinus rhythm maintenance after AF ablation on hard endpoints from a large multicenter cohort in the DOAC era. Interestingly, the reduction in the primary endpoint by sinus rhythm maintenance per se was considerable (HR 0.57) and was comparable to that of the AFFIRM study (HR 0.54).18, 19