Pulsed field ablation versus very high-power short-duration radiofrequency ablation in persistent atrial fibrillation: a single-centre experience

Abstract

Abstract Background Pulsed Field ablation (PFA) has recently emerged as a treatment strategy for patients with atrial fibrillation (AF) and early studies showed promising procedural data and durable pulmonary vein isolation (PVI). However, Very High-Power Short-Duration ablation (VHPSD) has previously reported good efficiency and mid-term outcomes, and only a few works compared these two procedures, especially in patients with persistent AF. Objective Our aim is to compare these different modalities of transcatheter ablation in patients with persistent AF, focusing mainly on some procedural aspects, safety and efficacy. Methods We performed a retrospective observational study enrolling all consecutive patients with persistent AF from September 2021 to May 2023 undergoing transcatheter ablation with PFA or VHPSD. In the first group, PVI was achieved by 2kV pulses with eight applications to each vein using both catheter configurations, while isolation of the posterior wall of the left atrium was achieved by applications through the only "flower" configuration; additional lesions were then added at the operator's discretion. In the second group, PVI was achieved by delivering 90W radiofrequency pulses for 4 seconds in the posterior portions of the left atrium and 50W pulses in the anterior region of the pulmonary veins; additional lesions were occasionally applied. All patients received general anaesthesia or deep sedation with fentanyl and dexmedetomidine. Results A total of 79 patients were included, n = 24 (30%) in the PFA group and N = 55 (70%) in the VHPSD one: early persistent AF (n= 2 [8,3%]; N = 7 [12,7%]), persistent AF (n= 17 [70,8%]; N = 36 [65,5%]), long-standing persistent AF (n= 5 [20,8%]; N = 12 [21,8%]). The two populations showed similar clinical features: CHA2DS2-VASc (median value 3 [0-6] in PFA vs 2 [0-6] in VHPSD, p = 0,10), indexed left atrial volume (mean value 42,6 ml/m² in PFA vs 42,4 ml/m² in VHPSD, p = 0,07) and EF (mean value 55,4% in PFA vs 54,8% in VHPSD, p = 0,33). PVI was successfully achieved in all patients. Nevertheless, the PFA group was associated with shorter procedural duration (92,1 ± 36,9 vs 134,2 ± 36,1 minutes, p = 0,00001) but longer fluoroscopy time (25,5 ± 9,3 vs 17,4 ± 11,5 minutes, p = 0,001); it also showed a lower rate of minor complications (n = 1 [4,2%] vs N = 3 [5,5%], p = 0,057), even though serious complications were not observed in either group. After a median follow-up of 14 (9-26) months, n = 19 [79.2%] in the PFA and N = 43 [78.2%] in the VHPSD population were free of any atrial arrhythmia (p = 0,92). Conclusion PFA allows faster procedures, representing a major advantage for the operator and the patient, who is at lower risk of peri-procedural complications. On the other hand, VHPSD correlates with shorter fluoroscopy times, reducing exposure to ionizing radiation. Finally, the two procedures show similar mid-term efficacy in terms of recurrence-free time.