Catheter Ablation -> Atrial Fibrillation & Atrial Flutter: -> Ablation Techniques D-AB07 - Alternate Techniques in Energy Sources (ID 6) Abstract Plus

D-AB07-05 - Preclinical Comparison Of Esophageal Effects Of Pulsed Field Ablation Vs Radiofrequency Ablation Using A Circular Multipolar Ablation Catheter System (ID 746)


Background: Pulsed field ablation (PFA) is expected to result in less collateral injury due to its unique preferential effect on myocardium.
Objective: To compare the effect of biphasic PF vs RF ablation in a novel esophageal injury model.
Methods: Under general anesthesia, in 9 healthy swine, the esophagus was deflected towards the IVC using an esophageal deviation device (DV8, MSS Inc) under fluoroscopic guidance. A circular multielectrode catheter (Biosense Webster) was deployed through a deflectable sheath in the IVC at sites adjacent to the esophagus. Biphasic PFA (900V over ≤ 4 heartbeats/lesion) was performed in 7 swine and RFA (20W, for 30 sec/lesion) in 2 swine from all electrodes adjacent to the esophagus with the same catheter but with different generator. Discrete esophageal sites (3-5) were targeted, with 6-8 PF lesions/site or 1 lesion/site in RF group. Ablation was also performed in atria (2 PF lesions/site or 20W/30second for RF) to confirm ablative efficacy at these doses. Animals were sacrificed at 3 weeks.
Results: All swine completed follow up, with no abnormal in-life observations. At necropsy, no swine (0/7 , 0%) in PFA group had evidence of lesions. In contrast, esophageal lesions were evident in 1 of 2 (50%) RFA swine: the lesion was visible on the outer surface (area =1.93 cm2) with no mucosal involvement (partial thickness of esophageal wall). Both PFA and RFA resulted in comparable endocardial lesions (gross measurement only) at ablation sites in both atria.
Conclusion: This study indicates that despite supra-clinical (3-4 X) doses, biphasic PFA as delivered using a circular multielectrode ablation catheter results in no visible damage to the esophagus in comparison to RFA.