Arrhythmia non-inducibility as the procedural endpoint of pulsed field ablation for paroxysmal atrial fibrillation: results of a prospective randomized comparison with pulmonary vein isolation without
M Fiala, F Lehar, M Cernosek, J Jez, V Bulkova, M Funasako, L Rybka, P Lokaj, O Toman, P KalaAbstract
Introduction
In the era of radiofrequency ablation (RFA), extra pulmonary vein (PV) ablation adjunctive to PV isolation (PVI) and arrhythmia non-inducibility (NI) as the procedural endpoint failed to improve outcomes in paroxysmal atrial fibrillation (PAF) patients. The absence of benefit from extra-PV ablation in suitable patients may not have been a matter of principle, but rather a consequence of imperfect RF lesions.
Purpose
To assess whether pulsed field ablation (PFA) (Faapusle) of possible extra PV sources with the effort to achieve AF or atrial tachycardia (AT) non-inducibility as the procedural endpoint improves outcome in patients with PAF.
Methods
Between 1/2023 and 12/2024, 334 patients with de novo PFA for PAF (62±11 years, 70 females) were randomized to PVI + extra PV ablation in case of induced (n=146) or spontaneously continuing AF/AT after PVI (n=21) with the desired endpoint of AF/AT termination and final NI (Group 1; NI tested; n=167) vs. only PVI in case of SR after PVI (n=145) or extra PV ablation to restore sinus rhythm (SR) in case of spontaneously continuing AF/AT, but without further attempts to attain AF/AT non-inducibility (n=22) (Group 2; NI non-tested; n=167). Procedures were performed under general anaesthesia, and non-inducibility was tested with incremental/ramp pacing up to CL ≥200 ms.
Results
In Group 1, AF/AT was induced in 38 (26%) of the 146 patients with SR after PVI, with termination into SR in 37 (97%), and NI achieved in 33 (87%). In addition, AF/AT spontaneously continuing after PVI was terminated in 18/21 (86%) vs. 16/22 (73%) patients of Groups 1 vs. 2, respectively, with final NI achieved in 16/21 (76%) patients of Group 1. In Group 1 vs. Group 2, after follow-up of 23±7 months, freedom from AF/AT recurrence (≥30s) reached 141 (84%) vs. 125 (75%) (Log Rank p = 0.0309), which was driven mainly by the difference between the subgroups with spontaneously continuing AF/AT after PVI - 18 (86% vs. 12 (55%) (Log Rank p=0.0273), although there was also trend to difference between the subgroups with SR after PVI - 123 (84%) vs. 113 (78%) (Log Rank P = 0.1742) (Figures).
Conclusions
In the group of PAF patients assigned to non-inducibility testing, AF/AT was induced after PVI in 26% of cases, with another 13% of patients having AF/AT spontaneously continuing after PVI. Additional PFA to restore SR and to achieve AF/AT non-inducibility was associated with improved clinical outcome.PFA non-inducibilityAF/AT after PVI