Transmural ablation of the normal porcine common bile duct with catheter-directed irreversible electroporation is feasible and does not affect duct patency

Background and aims: The aim of this study was to evaluate the feasibility and early safety of catheter-directed irreversible electroporation (IRE) of the normal common bile duct (CBD) in swine.

Methods: IRE (2000 V, 90 pulses, 100 μs pulse) was performed in the CBD of 6 Yorkshire pigs using a catheter electrode under endoscopic guidance. Ductal patency was assessed with immediate retrograde cholangiography and contrast-enhanced CT imaging at 1 or 7 days after treatment. Animals were killed at either 1 day (n = 4, 2 ablations/animal) or 7 days (n = 2, 1 ablation/animal) after treatment. The biliary tract was extracted en bloc and the length of the ablation along the CBD mucosa was measured. The depth of ablation was quantified using cross-sections of the treated CBD wall stained with hematoxylin and eosin. Single-sample hypothesis testing was performed to verify whether the depth of ablation in the CBD was a representative outcome of IRE treatment.

Results: IRE of the CBD did not result in perforation or obstruction of the organ at 1 or 7 days after treatment. The length of ablation along the CBD mucosa was 17.27 ± 5.55 mm on day 1 samples, and transmural ablation of the CBD wall was a representative outcome of the treatment (7/8 samples, P < .05). Day 1 samples demonstrated loss of epithelium, transmural necrosis, with preservation of lumen integrity. Day 7 samples demonstrated re-epithelialization, with diffuse transmural fibrosis of the CBD wall. These findings were absent from sham tissue samples.

Conclusions: Intraluminal catheter-directed IRE is feasible and safe for full-thickness ablation of the normal porcine CBD without affecting lumen patency up to 1 week after treatment.