Changes in the distribution of hepatic arterial blood flow following TIPS with uncovered stent and stent-graft: An experimental study

Purpose: To evaluate changes in distribution of hepatic arterial blood flow in the liver following insertion of an uncovered stent and subsequently a stent-graft in the transjugular intrahepatic portosystemic shunt (TIPS) channel. Methods: The experiments were performed in eight healthy pigs under general anesthesia. In a pilot study in one pig, scintigraphic evaluation of arterial perfusion to the liver was done before and after inflation of a balloon in the right hepatic vein. In the other pigs, outflow from the right liver vein was checked repeatedly by contrast injection through a percutaneously inserted catheter. The arterial perfusion through the liver was examined by scintigraphy, following selective injection of macro-aggregate of ⁹⁹Tc^m-labeled human serum albumin ⁹⁹Tc^m-HSA) into the hepatic artery. This examination was done before and after creation of a TIPS with an uncovered stent and subsequently after insertion of a covered stent-graft into the cranial portion of the shunt channel. Results: In the pilot study changes in the arterial perfusion to the liver were easily detectable by scintigraphy. One pig died during the procedure and another pig was excluded due to dislodgement of the hepatic artery catheter. The inserted covered stent obstructed venous outflow from part of the right liver lobe. The ⁹⁹Tc^m-HSA activity in this part remained unchanged after TIPS creation with an uncovered stent. A reduction in activity was seen after insertion of a stent-graft (p = 0.06). Conclusion: The distribution of the hepatic arterial blood flow is affected by creation of a TIPS with a stent-graft, in the experimental pig model.