Procedural workflow and long-term outcomes of pulsed-field ablation as a repeat procedure in comparison with conventional radiofrequency ablation in patients with paroxysmal atrial fibrillation

Abstract Background Repeated procedures are often needed for long-term success of atrial fibrillation (AF) ablation. There are scarce data regarding electroporation by means of pulsed-field ablation (PFA) use for such procedure. Purpose We analyzed procedural workflow and long-term outcomes of the Farapulse PFA system as a repeat procedure in comparison with conventional radiofrequency (RF) ablation in patients with paroxysmal AF. Methods Consecutive patients undergoing repeat ablation for paroxysmal AF, enrolled in the ATHENA-CHARISMA registries with complete follow-up data, were included. RF ablation cases were matched to initial PFA cases based on age, sex, left ventricular ejection fraction (LVEF), and comorbidities. In the PFA group, pulmonary vein isolation (PVI) was conducted following a protocol with 8 applications per PV. For RF ablation, circular lesions were created at each PV antrum with 45-50W. Additional lesions were applied at the operator's discretion. Results A total of 253 patients were included: 175 (69%) underwent RF ablation, and 78 (31%) underwent PFA. Mean age was 61±11 years, mean LVEF was 58±6%, 26.9% (n=68) of the patients were female and 19% (n=48) had a history of AT/AFL. In the PFA group, extended lesion sets beyond PVI were more commonly applied (29.5% for PFA vs. 14.3% for RF, p=0.006), while use of a 3D mapping system was lower (41% for PFA vs. 100% for RF, p<0.0001). Skin-to-skin procedural time and time to achieve PVI were shorter in the PFA group (75[51-94] min vs. 120[74-150] min, p<0.0001, and 20[15-26] min vs. 29[10-60] min, p<0.0001, respectively), whereas fluoroscopy time was longer (17[12-24] min vs. 12[8-17] min, p<0.001). No differences were observed between groups in the total number of PFA/RF energy applications (32[32-42] vs. 33[13-55], p=0.0851). PVI was achieved in all patients. Over a median follow-up of 377[302-450] days, 40 patients (15.8%) experienced AF recurrence beyond the 90-day blanking period. Energy source (PFA vs. RF) was not associated with AF recurrence (hazard ratio=1.43, 95% CI: 0.73 to 2.77, p=0.296). No major complications, including death, renal failure, esophageal complications, PV stenosis, or persistent phrenic nerve injury, were reported. Conclusion Our analysis indicates that the PFA system, when used for repeat ablation of paroxysmal AF, offers improved procedural efficiency compared to conventional RF ablation, with long-term outcomes comparable to those observed with RF ablation.