Endoscopic truncal vagotomy, a technical feasibility study. These are our disclosures. Surgical vagotomy involves bilateral transection of the vagus nerve trunks at the gastroesophageal junction. Surgery continues to be the standard of care in patients with refractory hyperacidity syndromes and patients with contraindications to prolonged anti-secretory medical therapy. Endoscopic truncal vagotomy may represent a novel minimally invasive approach that replicates the acid-suppressive effects of traditional surgical vagotomy. The study was conducted at a United States Department of Agriculture licensed facility under an active protocol that was approved by our institutional IRB. A large Yorkshire pig that weighed 170 pounds was used. The animal was sedated and placed on a ventilator and vitals were monitored throughout. After completion of the procedure, the animal was euthanized. Using weight-based doses of sonium phenobarbital, a necropsy was performed. Using a linear echoendoscope, the esophagus and mediastinal structures were evaluated. Two linear cord-like structures were identified in the anterior and posterior lower esophagus. The endosonographic appearance was compatible with that of a medium to large-sized nerve, i.e., a hyperechoic outer layer with a hyperechoic reticular center. After identifying the anterior and posterior vagus nerves, we used a 22-gauge FNA needle to inject 2 cc's of India ink immediately adjacent to the cord-like structures both in the anterior and posterior mediastinum. Following this, using a standard gastroscope fitted with a clear cap, a submucosal injection of methylene blue and saline was made along the anterior wall of the mid-lower esophagus. A triangle tip electrosurgical knife was then used to create a mucosotomy and the scope was advanced into the third or submucosal space and a 4-5 cm tunnel was created. We then proceeded with a full thickness myotomy 3-4 cm below the mucosotomy and the endoscope was cautiously advanced into the defect. Caution was exerted not to transect the adventitia. The adventitia was subsequently injected with a solution of methylene blue and saline and expanded just like the submucosa would. The scope was then advanced into the periasophageal adventitial space. Using electrocautery, the adventitial or fourth space was carefully dissected and the endoscope was advanced creating a tunnel. In order to identify the vagus nerve, we advanced the tunnel towards the previously placed tattoo. Here we identified a white non-pulsating cord-like structure compatible with the vagus nerve. The nerve was isolated cautiously using a triangle tip knife and transected with a scissor type electrosurgical knife. A piece of nerve tissue was eventually harvested for pathological confirmation. Following this, the scope was cautiously withdrawn from the tunnel. The mucosotomy was then completely closed with hemoclips and the same procedure steps were performed on the posterior esophageal wall and the posterior vagal trunk was successfully transected. On necropsy, both the anterior and posterior vagus nerves appeared to be completely transected and a leak test of the esophagus was negative. Of note, the India ink appeared to be immediately adjacent to both the anterior and posterior vagus nerves indicating reliable EUS identification. On necropsy, we identified that both the anterior and posterior truncal vagotomy was successfully performed. Both nerves appeared to be completely transected. Post-closure, the esophagus was intact and a post-procedure leak test was negative. The carbon ink tattoos were immediately adjacent to the nerves. In conclusion, this porcine study demonstrates technical feasibility of endoscopic truncal vagotomy. In humans, this novel technique may provide a minimally invasive option for managing acid-related disorders in high-risk surgical candidates. Future studies are needed to validate its long-term efficacy, safety, and impact on gastric physiology. Technique standardization and procedural refinements may position endoscopic truncal vagotomy as a valuable addition to the therapeutic armamentarium for acid suppression, particularly in high-risk surgical candidates. Thank you for your attention.

endoscopic truncal vagotomy

minimally invasive

acid-related disorders

electrosurgical tools

vagus nerves