Purpose: The aim of this study was to evaluate the potential for intravenous vasopressin to reduce the risk of nontarget gastrointestinal embolization during transcatheter liver-directed cancer therapies in a porcine model.
Materials and methods: An angiographic catheter was used to select the celiac or common hepatic artery under fluoroscopic guidance in six anesthetized pigs. After angiography of the hepatic and splanchnic territories was performed, technetium-99m macroaggregated albumin ((99m)Tc-MAA) was injected through the catheter. Serial arteriograms were obtained before, every 5 minutes during, and after peripheral intravenous vasopressin infusion at 0.4 U/min for a minimum of 20 minutes. After 10 minutes of infusion, indium-111 ((111)In)-MAA was injected through the arterial catheter. Quantitative comparisons of liver and gastrointestinal activity using dual-isotope single-photon emission computed tomography (SPECT)/CT imaging were performed.
Results: Catheter angiography demonstrated reduced blood flow to the splanchnic vasculature while maintaining blood flow through the hepatic arteries during vasopressin infusion. Angiographic findings correlated with the relative distribution of (99m)Tc-MAA (before the vasopressin infusion) and (111)In-MAA (after the vasopressin infusion) on SPECT/CT. The increased ratio of liver to gastrointestinal tract activity during the vasopressin infusion was statistically significant (6.2:11.4, respectively; P = .018).
Conclusions: Intravenous vasopressin reduces arterial blood flow to the splanchnic vasculature while preserving hepatic arterial blood flow in a healthy porcine model. Intraprocedural vasopressin administration has the potential to benefit liver-directed cancer therapies by enhancing tumor targeting as well as preventing the unintended delivery of bland embolic, chemoembolic, or radioembolic agents into the gastrointestinal vascular territories.
Copyright © 2012 SIR. Published by Elsevier Inc. All rights reserved.