Feasibility of catheter-directed intraluminal irreversible electroporation of porcine ureter and acute outcomes in response to increasing energy delivery.

PURPOSE: To evaluate the feasibility of focal intraluminal irreversible electroporation (IRE) in the ureter with a novel electrode catheter and to study the treatment effects in response to increasing pulse strength.

MATERIALS AND

METHODS

Five IRE treatment settings were each evaluated twice for the ablation of normal ureter in 5 Yorkshire pigs (n = 1-4 ablations per animal; total of 10 ablations) with the use of a prototype device under ultrasound and fluoroscopic guidance. Animals received unilateral or bilateral treatment, limited to a maximum of 2 ablations in any 1 ureter. Treatment was delivered with increasing pulse strength (from 1,000 V to 3,000 V in increments of 500 V) while keeping the pulse duration (100 μs) and number of pulses (n = 90) constant. Ureter patency was assessed with antegrade ureteropyelography immediately following treatment. Animals were euthanized within 4 hours after treatment, and treated urinary tract was harvested for histopathologic analysis with hematoxylin and eosin and Masson trichrome stains.

RESULTS

IRE was successfully performed in all animals, without evidence of ureteral perforation. Hematoxylin and eosin analysis of IRE treatments demonstrated full-thickness ablation at higher field strengths (mucosa to the adventitia). Masson trichrome stains showed preservation of connective tissue at all field strengths.

CONCLUSIONS

Intraluminal catheter-directed IRE ablation is feasible and produces full-thickness ablation of normal ureters. There was no evidence of lumen perforation even at the maximum voltages evaluated.