Ultra-microhistological study of nonthermal irreversible electroporation on the esophagus

Abstract

Esophageal ulceration and even fistula are severe complications of pulmonary vein isolation using traditional thermal ablation. Nonthermal irreversible electroporation (NTIRE) is a new technique for pulmonary vein isolation in patients with atrial fibrillation. NTIRE has been shown to be a safe method for pulsed electroporation near the esophagus. NTIRE preserves the structural framework of the esophagus and allows for rapid recovery of the whole layers of the esophagus. The purpose of this study was to elucidate the ultrastructural changes and cytological mechanisms of cell regeneration and tissue repair after esophageal electroporation. The parameter combination of 2000 V/cm multiplied by 90-pulse output was directly applied to the esophagus in 60 New Zealand rabbits, and ultrastructure analysis of the esophagus was implemented subsequently. NTIRE predominantly triggered apoptosis of esophageal cells shortly after electroporation. Since the tissue structural framework was preserved, esophageal cells could regenerate through self-replication within 4 weeks. Complete anatomical repair can eventually be achieved through structural remodeling, and no lumen stenosis, ulcer, or fistula was observed in the ablated segment. Monophasic, bipolar NTIRE pulses delivered using plate electrodes in an esophageal model demonstrates no irreversible ultra-micropathological changes to the esophagus after 4 weeks.