LAUSR

Abstract Funding Acknowledgements Type of funding sources: None. Background Atrial fibrillation (AF) represents the most common cardiac arrhythmia in adults worldwide. Catheter ablation (CA) of AF provides higher efficacy with comparable safety as antiarrhythmic drug therapy. Recently, high-power short-duration (HPSD) approach has emerged as an alternative to standard-power standard-duration settings, showing reduction in ablation times and increasing patient tolerability, with similar outcomes in terms of safety and efficacy. Although the advantages of general anesthesia (GA) are well established for standard-power standard-duration settings, there are currently no studies comparing GA to mild conscious sedation (MCS) for HPSD approach CA for AF. The aim of this study was to show whether GA improves procedural outcomes compared to MCS in AF CA using HPSD approach. Methods We included patients with paroxysmal or persistent AF who underwent HPSD CA using a contact-force sensing catheter (50W, ablation index 450 on the anterior wall and 320 on the posterior wall) either under GA or MCS. Procedural characteristics and success rates were compared between the two groups, as well as mid-term outcomes. Procedural safety was evaluated by intra- and post-procedural complications. Procedural efficiency was evaluated by total procedural time, number of radiofrequency applications, fluoroscopy time and dose. Acute success was defined as confirmation of entrance block in all pulmonary veins and mid-term success as freedom of AF at 6-months follow-up visits and re-do procedures. Results A total number of 131 patients were included in the study, 47 which underwent HPSD CA for AF under GA (group 1, mean age 60.2±10.2), and 84 under MCS (group 2, mean age 58.6±10.6). CA was performed for paroxysmal AF in 34 patients in group 1 (72.3 %) and 68 patients in group 2 (80.9 %), and for persistent AF in the remaining patients. We found lower mean total procedure time in the GA group (105.7±26.4 vs. 164.4± 41.9 min, p<0.0001), as well as lower radiation exposure (1310.0±1083.2 vs. 3060.5± 2254.8 μGy, p<0.0001 and 4.9± 2.8 vs 9.4± 7.5 min, p<0.0001) and lower number of radiofrequency applications (70.4± 20.4 vs. 106.0± 30.2, p<0.01). At the 6-months follow-up AF recurrence rate was lower in GA group (21.2% vs. 33.3%), however without reaching statistical significance (p=0.14). There was one moderate pericardial effusion in the MCS group which remitted with pharmacological treatment. Conclusion This is the first study comparing GA to MCS for AF CA using HPSD approach. Our findings demonstrate that GA improves procedural efficiency and suggest lower AF mid-term recurrence when HPSD AF CA is performed under GA, compared to MCS.