104 Safety and eighteen month efficacy of pulsed field ablation in a UK cohort

Introduction Pulsed field ablation (PFA) is a novel technique used in the treatment of atrial fibrillation (AF). This is an alternative to radiofrequency/cryoablation, which are the current mainstays of ablation treatment. The Farapulse (BSCI) PFA system was first introduced into the UK in 2022 at Royal Papworth Hospital. Our objective is to describe the safety and efficacy of PFA in the first 2 years after introduction at a UK tertiary electrophysiology centre. Methods Patients undergoing PFA for AF at a single UK centre in the first eighteen months with confirmed follow-up data were included in a prospective registry. Recurrences of AF after a 90-day blanking period were defined as >30s documented AF. Patients were followed up routinely within 3 months via ECG, or by Holter monitor if they experienced symptoms. Results 123 patients (age 64 ± 10 years, Male 71%, CHA2DS2VASc score 1.8 ± 1.4, BMI 30 ± 6, Left ventricular ejection fraction < 45% = 14%), were treated using the Farapulse system between June 2022 and December 2023 by 4 operators. 18 cases were redo procedures (15%). 71 (58%) patients had paroxysmal AF (PAF) and 52 (42%) had persistent AF (PeAF), with 10 (8% of total) undergoing posterior wall isolation in addition to pulmonary vein isolation. All procedures were undertaken under GA and 12 (10%) with TOE guidance. 27 cases (22%) used 3D anatomic mapping. Procedure duration was 111 ± 30 min. All pulmonary veins and posterior walls were successfully isolated acutely. Two patients failed to maintain sinus rhythm at the end of the procedure. However, they spontaneously reverted to sinus rhythm during the blanking period. The risk profile for the Farapulse procedure is compiled below, showing 5 patients (4.1%) experienced serious adverse events: 2 patients suffered strokes, 2 patients experienced pericardial effusions which were managed with no further sequelae, 1 patient required intervention following a vascular access problem. There were 10 patients (8.1%) who suffered minor vascular access complications (haematomas) which did not require intervention. No adverse complications specific to the Farapulse technology occurred. At the end of the 18-month observation period, freedom from PAF was reported to be 82%, and freedom from peAF was 62% (p = 0.03 between the two groups). Conclusion 18-month follow-up data shows that the Farapulse ablation procedure has a good safety profile (4.1% serious adverse event rate), with promising medium-term efficacy (82% freedom from AF for PAF, 62% for peAF). We await 5 year survival data which will allow for better comparison between PFA and other ablation methods. Conflict of Interest None