Po-02-039 the effect of pulsed-field ablation field strength and number of applications in acute pulmonary vein isolation: a preclinical study

Pulsed-field ablation (PFA) is an emerging non-thermal tissue-selective ablative technology that can be used for pulmonary vein isolation (PVI). A single pulse of PFA can result in reversible electroporation. The PFA field strength and the number of applications required to transform reversible electroporation into irreversible require further investigation. This study evaluates the effect of PFA field strengths and the number of PFA applications on acute PVI. An 8-French purpose-designed adjustable loop 10-electrode catheter was used to deliver three different PFA field strengths to fifteen healthy swine pulmonary veins (mean weight= 37.8 ± 3.8kg). The procedures were performed under general anesthesia. The animals were divided into three groups, each group receiving low, intermediate, and high field strength of PFA: 1800 (n= 4), 2300 (n= 4), and 2800 Volts (n=7), respectively. Each field strength was applied 6, 8, and 11 times, respectively. The number of PFA applications were predefined. Acute success was determined by immediate bi-directional PVI. The right phrenic nerve integrity was tested pre and post-ablation. Successful acute PVI was achieved in 26 out of 27 veins (96.3%) without any evidence of PFA-related adverse events. The only vein not electrically isolated was in the intermediate voltage group (2300V) with a total number of 8 applications. In contrast, other veins that were ablated with the lowest and highest voltage and ablation repetitions demonstrated immediate electrical isolation. No phrenic nerve palsy was observed at the end of the procedures. PFA effectively achieves PVI with low voltage and adequate ablation repetitions. The highest voltage with the highest ablation repetitions was demonstrated to be safe.