Clinical impact of early recurrence of atrial fibrillation after catheter ablation on subsequent ischemic stroke: STOP-OAC study

Background / Introduction

Regarding oral anticoagulation therapy after catheter ablation for atrial fibrillation (AF), the European Society of Cardiology guidelines recommend continuing oral anticoagulation after AF ablation according to the patient’s CHA2DS2-VA score (Class I). The Japanese Circulation Society guidelines provide a Class IIa recommendation that oral anticoagulation should generally be continued in patients with a CHADS2 score ≥2.

Early recurrence of atrial fibrillation (ERAF) after AF ablation is well recognized as a risk factor for late recurrence. However, no studies have specifically evaluated the association between ERAF and the incidence of post-ablation ischemic stroke.

Purpose

This study aimed to elucidate the association between ERAF and subsequent ischemic stroke events.

Methods

We retrospectively analyzed 1,596 patients with a CHADS2 score ≥2 who underwent their first catheter ablation for atrial fibrillation between April 2021 and March 2024, using a multicenter database from eight institutions in Japan.

Patients were categorized into two groups: the ERAF+ group, defined as those who experienced recurrence of atrial tachyarrhythmia within three months after ablation, and the ERAF− group, defined as those without recurrence during the same blanking period.

The cumulative incidence of ischemic stroke was estimated using Kaplan–Meier survival analysis and compared between the two groups using the log-rank test. Multivariable Cox proportional hazards regression analysis was performed to evaluate the association of ERAF and established predictors of AF recurrence with subsequent ischemic stroke events.

Results

Among 1,596 patients, 290 (18.2%) developed ERAF. The ERAF+ group demonstrated a significantly higher rate of late AF recurrence at 6 months (38.6% vs. 12.1%, p < 0.001) and a significantly lower rate of oral anticoagulation discontinuation (24.2% vs. 31.3%, p = 0.017) compared with the ERAF− group.

In addition, the ERAF+ group had a significantly higher incidence of ischemic stroke (p = 0.012), whereas no significant difference was observed in bleeding events (p = 0.152).

Univariable analysis showed that ERAF was the only variable significantly associated with ischemic stroke. Furthermore, multivariable analysis identified ERAF as an independent predictor of post-ablation ischemic stroke events. These findings suggest a potential association between early arrhythmia recurrence after ablation and an increased thromboembolic risk.

Conclusions

Among patients with a CHADS2 score ≥2 undergoing catheter ablation for atrial fibrillation, those who experienced ERAF had a significantly higher incidence of ischemic stroke. ERAF was identified as an independent risk factor for post-ablation ischemic stroke. These findings suggest that continued oral anticoagulation may be warranted in patients with ERAF.ischemic stroke Log-rankanalysis