Abstract 21415: Use of High Power Radiofrequency versus Low Power for Ablation of Atrial Fibrillation: Feasibility and Safety

Abstract

Introduction: Radiofrequency Catheter ablation (RFCA) has become an established strategy to treat symptomatic and drug refractory cases of Atrial Fibrillation (AF). Despite its safety, RFCA accompanies some serious complications such as esophageal thermal damage, that makes physicians more cautious while ablating the posterior structures and avoid using higher powers for RFCA. Hypothesis: We aim to investigate the safety of 50 watts RFCA compared with 35 watts, by the novel method of detecting any esophageal enhancement with Late Gadolinium Enhancement MRI (LGE-MRI). Methods: Records of 511 AF patients from 2012 to 2016 were collected; who underwent RFCA and had LGE-MRI post-ablation to detect any esophageal injury. The method of ablation for both groups includes Pulmonary Vein Isolation (PVI) and Posterior Wall Debulking (PWD). Patients were categorized into 2 groups: The High Power (HP) group who underwent ablation with 50 Watts catheters and the Low Power (LP) group, for whom the 35 Watts catheters were used. With regard to their respective esophageal enhancement, patients were classified as those who had no, mild, moderate, or significant esophageal enhancement. Results: There were 459 patients in HP group (301 men; mean age 70.4 ± 11.2) and 52 patients in LP group (32 male; mean age 64.1 ± 11.7). HP group was significantly older (p < 0.05) and persistent type of AF was more common among them (51.5% vs 25%, p < 0.05). The incidence of esophageal enhancement post-ablation was not significantly different among HP and LP groups (Figure 1) but the procedure time was significantly shorter for HP group (149.3 ± 64.8 minutes vs 308.4 ± 104, p < 0.001). None of our patients (in both groups) developed serious complications such as atrioesophageal fistula. Conclusions: Using high power radiofrequency catheter ablation for AF patients shows no correlation with esophageal enhancement post-PWD ablation, furthermore they can significantly reduce the procedure time.