Initial evaluation of a novel, prototype, forward-viewing echoendoscope in a porcine arterial bleeding model (with video).

Abstract

BACKGROUND: Real-time visualization of submucosal arterial flow at the base of an ulcer might improve endoscopic hemostasis by permitting more accurate assessment of the artery, precise targeting of therapy, and confirmation of vessel ablation. OBJECTIVE: To evaluate the utility of a novel, forward-viewing echoendoscope in identifying bleeding submucosal arteries, guiding hemostatic therapy, and confirming cessation of flow through treated vessels. DESIGN: In 7 pigs, a previously described porcine model for peptic ulcer hemorrhage was created by isolating the gastroepiploic and/or short gastric artery and tunneling it into the subserosal space at laparotomy. SETTING: Animal research facility. INTERVENTION: The prototype endoscope was used to image submucosal arterial flow. EUS guidance was then used to deliver endoscopic hemostatic therapy and assess treatment adequacy. MAIN OUTCOME MEASUREMENTS: Identification of the target submucosal artery and successful delivery of EUS-guided endoscopic therapy, evidenced by cessation of Doppler flow through the target vessel. RESULTS: Tunneled arteries were visualized endosonographically in all 7 cases. EUS-guided submucosal injection of epinephrine was successful in 2 of 2 cases. EUS-guided delivery of thermal hemostatic therapy was successful in 2 of 4 cases. Absence of flow through treated vessels was confirmed in cases in which EUS-guided therapy was successfully delivered. LIMITATIONS: Acute animal model. CONCLUSION: Proof of principle experiments in a porcine peptic ulcer hemorrhage model suggest that real-time sonographic imaging of submucosal arteries is feasible with a forward-viewing echoendoscope, and guided hemostatic therapy can be delivered.