Minimal invasive removal of a dislocated stent for flow reduction of a transjugular intrahepatic portosystemic shunt
Transjugular intrahepatic portosystemic shunt (TIPS) insertion is a minor invasive and preferred treatment option for portal hypertension which is refractory to medical therapy. By creating a transhepatic bypass and thus reducing pressure in the portal venous system, common indications for TIPS insertion are for variceal hemorrhage, recurrent ascites, acute portal vein thrombosis or Budd-Chiari syndrome, bridging before liver transplantation or severe liver insufficiency. After TIPS insertion a multitude of complications such as cardiac or liver failure as well as hepatic encephalopathy can occur if the newly created bypass leads to a functional exclusion of the liver from the portal venous circulation and the blood is directly diverted to the caval circulation. Here, the increased blood volume might lead to right heart failure. Hepatic failure might be induced by the significantly reduced intrahepatic portal venous blood flow, thus decreasing hepatic perfusion leading to hepatic damage by ischemic necrosis (Li et al. Turk J Gastroenterol 2019; 30: 702–707). Second, by accelerating the transfer of neuroendotoxins (especially ammoniac) directly into the inferior caval vein, hepatic encephalopathy might occur, especially in the first three months after TIPS insertion (Lotterer, Erich; Universitäts- und Landesbibliothek Halle 2004; ACNO: ulb.38 884 177X). In most patients, conservative treatment is possible. Hepatic encephalopathy can be treated by lowering blood’s ammoniac concentration. Here, a protein-restricted diet, cleaning the intestinal tract with lactulose or by branched-chain amino acids can be successful (Suhocki et al. Semin Intervent Radiol 2015; 32: 123–132). To avoid TIPS embolisation, which often entails severe consequences, e. g. liver failure or variceal hemorrhage, stent reduction can be considered as a viable alternative. Bare metal stents, which are nowadays commercially available with an hourglass configuration, often imply an unpredictable portal pressure reduction (Taylor et al. Tech Vasc Interv Radiol 2016; 19: 74–81). It is inserted into the original shunt, aimed at reducing the shunt flow and increasing the pressure gradient, thus potentially improving the patient’s clinical condition. Finally covered stents can be introduced, tailoring a central narrowing of it by different means. Two possible approaches would be placing a small stent parallel to the additional covered stent to cause this narrowing, or to underinflate the central part of the covered stent. However, the technical challenge is the appropriate deployment of the stent graft within the preexisting TIPS and complications are possible, but can be dealt with, just as described in this case report.
03 September 2020 (online)
© Georg Thieme Verlag KG
Stuttgart · New York