Late thromboembolic events after circumferential pulmonary vein ablation of atrial fibrillation

Catheter ablation can restore sinus rhythm in selected patients with atrial fibrillation (AF), but its preventive function for thromboembolic events (TE) is still underdetermined. We retrospectively studied 520 consecutive patients with AF who were referred for circumferential pulmonary vein ablation. The incidence of late TE was investigated, and the predictors of late TE were identified from analysis of the basic clinical variables of patients with late TE. Eight (1.5%) patients experienced late TE during 28 +/- 8 months follow-up. When TE occurred, most (6/8, 75%) patients were documented with recurrence episode. The recurrence of AF was more frequent in patients with late TE than patients without late TE (75.0% vs 30.5%, P = 0.007). Multivariate logistic regression analysis identified that all risk factors, including all clinical variants prior ablation and the CHADS(2) score, were not related to late TE but the presence of recurrence was the only predictor of late TE (odds ratio, 5.542; 95% confidence interval [1.416-45.013], P = 0.019). Our study demonstrates a strong relationship between the recurrence after ablation and TE post-operation and supports the proposal that free of recurrence is an indication for discontinuation of anticoagulation after ablation.