Abstract 14293: Silent Thromboembolic Lesions Following Catheter Ablation for Atrial Fibrillation Using Radiofrequency Energy: Results From a Sub-study of the "compare" Randomized Trial
Introduction: Silent thromboembolic lesion (STL) has been reported in 14% of the cases following catheter ablation of atrial fibrillation with radiofrequency energy (RF) and with warfarin discontinuation before AF ablation procedures.
We sought to determine whether the anticoagulation management plays a role in the occurrence of STL in a randomized multicenter study.
Methods: This was an open-label, randomized, parallel-group, multicenter study assessing the role of continuous warfarin therapy in preventing periprocedural thromboembolic and hemorrhagic events after radio frequency catheter ablation. Patients with CHADS2 score ≥ 1 were included in the study. Patients were randomly assigned to the off-warfarin or on-warfarin arm. In a subset of the enrolled patients, pre and post ablation dMRI was performed to assess the prevalence of STL. All statistical tests were two-sided and a P-value <0.05 was considered statistically significant.
Results: The main study enrolled 1584 patients while 96 underwent dMRI. 48 pts were assigned to group 1 (discontinue warfarin) and other 48 pts to group 2 (continuous warfarin (group 2). The two groups did not differ in their baseline characteristics. At post-procedure MRI, SLT was detected in 8 (16.7%) patients in group I and 1 (2.1%) patients in group II (p= 0.031). The patient in group II (continuous warfarin) had a small single lesion (2.5 mm). In group I (discontinue warfarin), the lesions vary widely in length: 4-24 mm diameter. After adjusting for clinical covariates, warfarin discontinuation was the strongest predictor of post-procedure SLT [OR 9.4 (95% CI 1.2 to 78) p=0.03]. In addition cardioversion was not associated with SLT [OR 2.4 (95% CI 0.37 to 24) p=0.46].
Conclusions: This is the first randomized multicenter study showing that performing catheter ablation of atrial fibrillation without warfarin discontinuation statistically reduces the occurrence of silent thromboembolic lesion.
- © 2013 by American Heart Association, Inc.