DOES PULSED FIELD ABLATION OF THE POSTERIOR LEFT ATRIUM WITH THE PENTASPLINE CATHETER RESULT IN TRANSMURAL NECROSIS?

Background: PFA to create irreversible electroporation is rapidly being adopted as a new standard for AF ablation. Because of the esophageal sparing associated with PFA, LA posterior wall (LAPW) ablation is increasingly being performed during AF procedures, but less is known about the depth of the lesion.
Objective: To study whether endocardial PFA of the LAPW with the pentaspline catheter results in transmural ablation.
Methods: This prospective single-center study enrolled pts with persistent AF planned for first-time PFA using the pentaspline catheter (Farawave; Boston Scientific Inc). Pericardial access was first achieved (using a novel pericardial needle [PeriCross; Circa Scientific Inc] as part of a concurrent clinical trial). After baseline epi- and endo-cardial voltage maping (Pentaray/Carto; JNJ MedTech Inc), PFA was performed in usual fashion for PVI (flower & basket), followed by overlapping LAPW lesions in flower pose (2 applications per position). Post-PFA, epi- and endo-caridal voltage mapping was repeated. Procedures were performed with deep sedation.
Results: The 18-patient cohort (age 64.8 ±9.3 yrs, 13M / 5F, BMI 27.6±6.9, EF 62.2±9.5%) included 16 pts with persistent AF and 2 pts with long-standing persistent AF. The mean procedure time was 106.4 min (range 60-227) and fluoroscopy time was 4.2 min (range 1.5-8.7). Among a mean of 59.5 (range 22 – 94) PF applications, a total of 21 (16-26) were applied to the LAPW. All PVs were isolated, and in 18 of 18 pts (100%), the LAPW was electrically isolated on both the endocardial and epicardial surfaces. There were no complications.
Conclusion: In our study of AF patients undergoing endocardial PFA of the PVs and LAPW with the pentaspline catheter, high-density electroanatomical voltage mapping of the endocardium and epicardium revealed trnasmural ablation of the LAPW.