Background: It is important to assess the risk of collateral injury to the esophagus with novel AF ablation technologies.
Objective: To investigate the esophageal effect of PFA delivered using a novel expandable 9 mm spherical lattice-tip catheter (Sphere-9, Affera).
Methods: Under general anesthesia, percutaneousfemoral venous access was obtained in 5 swine. The esophagus was deflected adjacent to the inferior vena cava (IVC) using an esophageal deviation balloon (DV8; Manual Surgical Sciences Inc). Using a 12Fr deflectable sheath, lesions were delivered with the lattice catheter in the IVC at areas contacting the deviated esophagus. In the PFA cohort (4 of 5 swine), 10.3±1.7 discrete PFA applications were delivered with forceful contact. In 1 swine, five RF lesions were placed with the same catheter; as this was to serve as a positive control of esophageal damage, an excessive RFA dose was chosen (temperature-controlled irrigated RF, 75℃ for 5 sec/lesion). All swine were sacrificed after 12.2±1.3days.
Results: All swine completed the follow up period. The weight increased by 11.4±7.4% and 5.4% in the PFA and RF cohorts, respectively. On gross necropsy, PFA swine demonstrated no evidence of esophageal lesions (0 of 4, 0%) in contrast to the RF control animal, where an esophageal fistula was seen. The size of the mucosal aspect of the fistula was 13.7 x 8.9 mm; it was densely adherent to the lung and IVC. All tissue was submitted for histological examination.
Conclusion: In this novel in vivo model of esophageal fistula, pulsed field energy delivered by the lattice-tip catheter did not affect the esophagus, thus demonstrating the tissue specificity of this non-thermal ablative energy.