Thromboembolic events 7-11 years after catheter ablation of atrial fibrillation

Background: The results of catheter ablation of atrial fibrillation (AF) beyond 6 years remain unknown. The goal of this study is to assess the risk of thromboembolic events (TEs) and outcomes of AF ablation at long-term follow-up (FU).

Methods: All patients who had AF ablation from 2002 until 2005 in our center were contacted for a FU including a questionnaire, cardiac rhythm monitoring, and transthoracic echocardiography.

Results: Among the 264 eligible patients, 164 (62%) completed the study. The mean FU was 9.1 years (7.7-10.5). Seven patients had a TE during FU (event ratio 0.41 per 100 patient years [PY]) and their mean CHA2DS2-VASc score was 3.1 ± 1.3. Two patients died from stroke (0.14 per 100 PY) and five of the seven were considered in sinus rhythm (SR) and were off anticoagulation at the time of event. Prior to ablation, 13 patients had history of TE, and only one had a TE during FU. Overall, 14 deaths were documented (0.58 per 100 PY). Stable SR was present in 111 patients (68% of 164 patients) after 1.5 ± 0.6 procedures/patient. Univariate analysis showed that dyslipidemia (odds ratio [OR] = 2.95, P = 0.003), CHA2DS2-VASc ≥2 (OR = 3.22, P = 0.001), and amiodarone (OR = 5.64, P < 0.001) were predictors of long-term recurrence. Multivariate analysis showed that only CHA2DS2-VASc ≥2 (OR = 2.67, P = 0.023) and amiodarone (OR = 4.62, P = 0.001) were predictors.

Conclusions: Our study shows low TE rates 9 years after ablation of AF that are lower than published data for AF patients with anticoagulation only. AF patients with a CHA2DS2-VASc ≥2 should, however, be maintained on anticoagulation.