Atrioventricular Dissociation During Pulsed Field Ablation Is Spatially Associated With Local Ganglionated Plexus Function

Abstract

Introduction Objectives: Pulsed field ablation (PFA) produces myocardial electroporation, sparing non-cardiac tissues, including autonomic structures. However, transient atrioventricular dissociation (AVD) can be observed during PFA delivery. Whether this represents direct neural stimulation of ganglionated plexi (GP) has not been established in humans. The objective was to determine whether transient AVD during endocardial PFA co-localises with functional left atrial (LA) GP sites. Method(s): Consecutive patients with persistent AF undergoing PFA with a pentaspline catheter were prospectively enrolled in the Personalised Ablation Strategies for AF study (NCT05633303). Systematic LA GP mapping was using high-frequency stimulation (HFS) (50 Hz, 100 V) in AF was performed with an irrigated-tip catheter to identify atrioventricular dissociation GP (AVD-GP) sites (defined as RR prolongation > 50% or asystole.) PFA applications were annotated on an integrated mapping system by vein, application order, and catheter configuration. Result(s): 531 PFA applications were delivered (384 (72.3%) ostial applications) across 10 patients (38 +/- 3 ostial applications per patient). 310 (58.4%) applications were delivered with the catheter in a flower configuration, and 221 (41.6%) in a basket configuration. Transient AVD occurred during 10 postal PFA applications in 4/10 (40%) patients, localised to 4/40 (10%) PV ostial segments, most commonly the left upper PV (3/4 (75%)). 11 PV ostial sites demonstrated overlying AVD-GPs on baseline HFS. PFA more frequently elicited transient AVD when applied to segments underlying AVD-GPs compared with segments without AVD-GPs (8/109 (7.3%) vs 2/275 (0.7%), p < 0.001). Overall, 3/11 (27.3%) ostial segments with AVD-GPs demonstrated transient AVD during PFA, which was reproducible on sequential overlapping applications in 2/3 segments. Transient AVD was observed during the first PFA application in each segment where it occurred. All AVD episodes resolved spontaneously without complication. Conclusion(s): Transient AVD during endocardial PFA occurs predominantly on application to PV-ostial segments containing functional AVD-GPs, supporting a GP-mediated autonomic mechanism. These findings suggest that PFA can acutely stimulate autonomic structures and may provide real-time, periprocedural localisation of overlying GPs.