Ultra-microhistological study of nonthermal irreversible electroporation on the esophagus

Background: 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.

Objective: The purpose of this study was to elucidate the ultrastructural changes and cytological mechanisms of cell regeneration and tissue repair after esophageal electroporation.

Methods: 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.

Results: 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.

Conclusion: Monophasic, bipolar NTIRE pulses delivered using plate electrodes in an esophageal model demonstrates no irreversible ultra-micropathological changes to the esophagus after 4 weeks.