Transjugular intrahepatic portosystemic shunt with silicone-covered wallstents: Results in a swine model

PURPOSE: To evaluate the use of impermeable silicone-covered Wallstents for trans jugular intrahepatic portosystemic shunt creation. MATERIALS AND METHODS: A transjugular intrahepatic portosystemic shunt was created in 14 young swine (weight, 20-32 kg) by using impermeable silicone-covered Wallstents. In eight animals, the silicone covering extended from the portal vein to the inferior vena cava. In two swine, the silicone covering ended short of the inferior vena cava, in two it ended short of the portal vein wall, and in two it ended short at each end. Follow-up transhepatic portal venography was performed weekly for 6 weeks or until the shunt was occluded. Animals were then sacrificed for gross and histologic evaluation. RESULTS: Only two of 14 shunts were patent after 3 weeks; both were stenosed with luminal narrowing of more than 50% in the middle of the shunt. By 6 weeks, all shunts were occluded. At histologic evaluation, a marked foreign-body reaction with superimposed thrombosis was demonstrated. CONCLUSION: In comparison with uncovered Wallstents, impermeable silicone-covered Wallstents are associated with decreased patency at transjugular intrahepatic portosystemic shunt creation. This is likely due to increased thrombogenicity and a foreign-body reaction.