Data sources and participants
The AF Frontier Ablation Registry (UMIN Clinical Trials Registry: UMIN000026849) is a multicenter cohort study whose study design has previously been described in detail.9 Briefly, the study included 3530 consecutive patients who underwent catheter ablation for AF at any of the 24 cardiovascular centers in Japan between August 2011 and July 2017. The clinical data, such as patient characteristics (e.g., age, sex, AF type, comorbidities, blood test results, echocardiographic characteristics, and drugs), catheter ablation findings, and follow-up data were retrieved from each hospital’s medical records. The follow-up data included information as to whether the AF had relapsed after catheter ablation, whether oral anticoagulants (OACs) or antiarrhythmic drugs (AADs) had been discontinued, and whether adverse events such as ischemic stroke, hemorrhagic stroke, transient ischemic attack (TIA), heart failure, acute coronary syndrome, or all-cause death had occurred. The dates of AF recurrence and occurrence of these adverse events were also recorded.
In this analysis, we included patients from the AF Frontier Ablation Registry who underwent a first catheter ablation for AF and completed the follow-up more than 3 months after the procedure. To avoid the effects of multiple ablation sessions, we excluded patients who underwent catheter ablation of AF more than once.
The patients consented to the use of their anonymized clinical data for research purposes through the opt-out program. The study protocol was approved by the institutional review boards of all 24 hospitals where the patients were treated.