Background: Pulsed field ablation (PFA) has recently been introduced as a novel ablation technology for atrial fibrillation (AF). However, data on chronic procedural outcome are sparse.

Objective: To investigate acute and chronic procedural success and safety in patients undergoing PFA for the treatment of AF.

Methods: Consecutive paroxysmal and persistent AF patients underwent PFA-based catheter ablation using a multi-spline catheter. PFA-based ablation procedures, including first and repeat ablation procedures, were performed with additional 3D electroanatomical mapping. Procedural parameters, acute success, safety and chronic outcome were assessed. Follow up was conducted by telephone interview, routine Holter-ECGs and control of implantable cardiac devices, if applicable.

Results: A total of 101 patients undergoing PFA from May 2021 until November 2022 in one German center were included in the study. Patients suffered from paroxysmal AF (n= 38; 38%), persistent AF (n=36; 36%) and consecutive atrial tachycardias (AT) due to previous catheter ablation (n=27; 26%). Mean age was 67 ± 14 years, median CHA2DS2-VASc Score was 2 (Q1-Q3: 1-3), mean left atrial diameter was 44 ± 9 mm and 83 of 101 (82%) patients had a normal left ventricular ejection fraction.

Of all PFA procedures, 61 (60%) were index ablation procedures and 40 (40%) were repeat procedures (including re-pulmonary vein isolation and/or left posterior wall isolation and/or conduction of roof, anterior and/or mitral isthmus lines). The median total procedure and left atrial (LA) PFA times were 98 (Q1-Q3: 61-121) and 34 (Q1-Q3: 24-47) minutes, respectively. Mean total fluoroscopy and LA PFA fluoroscopy times were 14 ± 7 and 9 ± 5 minutes. Successful PFA lesions were created in 100/101 patients (99%). In one patient, the use of radiofrequency ablation in the coronary sinus was needed to block the mitral isthmus line.

Total complication rate was 7.9% (8/101) including only one major complication (n=1 pericardial tamponade; 0,99%). Minor complications were found in 7 patients (1 coronary spasm without sequela, 2 minor groin AV fistulas, 1 cardiac decompensation, 1 transient intra-procedural AV-block, 1 aspiration, 1 macro hematuria). Preliminary follow up of 264 ± 138 days including 63 patients showed 83% freedom from arrhythmias (52/63 patients without recurrence).

Conclusion: In this initial experience, PFA applied in patients with atrial fibrillation demonstrates high chronic procedural success rates and a favorable safety profile.