PO-01-235 EPICARDIAL PULSED-FIELD ABLATION OF THE CARDIAC GANGLIONATED PLEXI: IMPACTS ON THE AUTONOMIC NERVOUS SYSTEM

Abstract

The autonomic nervous system (ANS) has been shown to play a role in the initiation and maintenance of atrial fibrillation (AF). While incidental ablation of the Ganglionated Plexi (GP) during AF ablation changes the ANS in a manner which correlates with procedural success, targeted ablation of GP has met with mixed results. In pre-clinical models, pulsed field (PF) energy delivered epicardially has demonstrated the capability to ablate GP without damage to surrounding myocardium. This is a first in human analysis to investigate the feasibility and safety of epicardial PF ablation (PFA) during cardiac surgery. In a single arm, prospective analysis, patients with or without a history of AF underwent epicardial PFA (OCED, AtriAN[RV1] Inc, Dublin) during planned coronary artery bypass grafting (CABG; see Figure). ANS tone was assessed via intraoperative pacing maneuvers to assess atrial effective refractoriness (AERP) and with Holter-assessment of heart rate variability (HRV) at baseline and 3 months post procedure. Most enrolled patients (23 of 24) received the full ablation protocol with no device-related adverse effects. Pacing demonstrated a 20.7±19.9% extension in AERP (P<0.001). Holter monitoring demonstrated an increase in mean heart rate (74.0±8.7 vs 80.6±12.3 BPM, P=0.01). While there was a trend towards a decrease in SDNN (188±31 vs 104±40, P=0.20), there were no significant changes in HRV. Post-operative AF (POAF) was noted in 7 (29%) of patients. This study demonstrates the safety and feasibility of epicardial PFA of the cardiac GP aimed at modulating the ANS during CABG. While changes in AERP suggest acute efficacy, assessment of the long-term effects and impact on the incidence of POAF is limited by the small sample size and single-arm nature of this analysis. Larger, randomized studies are needed to determine the long-term impact of epicardial PFA and its ability to mitigate POAF.