Focal Pulsed Field Ablation for Pulmonary Vein Isolation and Linear Atrial Lesions: A Preclinical Assessment of Safety and Durability

- A novel ablation and mapping system can toggle between delivering biphasic pulsed field (PF) and radiofrequency (RF) energy from a 9mm lattice-tip catheter. We assessed the preclinical feasibility and safety of: i) focal PF-based thoracic vein (TV) isolation and linear ablation, ii) combined PF and RF focal ablation, and iii) PF delivered directly atop the esophagus. - Two cohorts of 6 swine were treated with pulsed fields at low-dose (PF ) and high-dose (PF ) and followed for 4 and 2 weeks, respectively, to isolate 25 TVs and create 5 right atrial (PF ), 6 mitral (PF ) and 6 roof lines (RF+PF ). Baseline and follow-up voltage mapping, venous potentials, ostial diameters and phrenic nerve viability were assessed. PF and RF lesions were delivered in 4 and 1 swine from the inferior vena cava onto a forcefully deviated esophagus. All tissues were submitted for histopathology. - 100% of TVs (25/25) were successfully isolated with 12.4±3.6 applications/vein with mean PF times of