Author/Editor     Niyyati, Mahtab; Petersen, Bryan D; Pavčnik, Dušan; Uchida, Barry T; Timmermans, Hans A; Hiraki, Takao; Wu, Reng-Hong; Brountzos, Elias; Keller, Frederick S; Rösch, Josef
Title     A flexible stent with small intestinal submucosa covering for direct intrahepatic portocaval shunt: experimental pilot study in swine
Type     članek
Source     Cardiovasc Intervent Radiol
Vol. and No.     Letnik 28, št. 2
Publication year     2005
Volume     str. 215-20
Language     eng
Abstract     The suitability of the flexible sandwich Zilver stent-graft (SZSG) with a biologically active tissue layer (small intestinal submucosa) for creation of the intravascular ultrasound (IVUS)-guided direct intrahepatic portocaval shunt (DIPS) was explored in six young swine in a search for a flexible system to replace the rigid polytetrafluoroethylene (PTFE) stent originally used by this group with limited success. The portal vein was punctured from the inferior vena cava through the caudate lobe of the liver using IVUS guidance. After balloon dilation of the puncture tract, DIPS was successfully created in all animals with use of an SZSG 9 mm in diameter and 6 cm or 8 cm long. Only one DIPS remained well patent at 14 days when the animal had to be killed because of encephalopathy. DIPS in the other five animals were found to be either severely stenosed (3 animals) or occluded (2 animals) at 4 weeks due to accelerated formation of neointimal hyperplasia (NIH) in the liver parenchymal portion of the shunt and superimposed thrombosis. The lack of high pressure in the portal system contributed to early endograft closure. The flexible stent and the covering fail badly. The reason for this could be due to either component. More work is required to find a reliable flexible system with long-term patency. Exploration of the IVUS-guided direct extrahepatic portocaval shunt is suggested.
Descriptors     BIOPROSTHESIS
STENTS
ANIMALS
BALLOON DILATATION
DISEASE MODELS, ANIMAL
ENDOSONOGRAPHY
EQUIPMENT DESIGN
GRAFT OCCLUSION, VASCULAR
HYPERPLASIA
PILOT PROJECTS
PLIABILITY
PORTAL VEIN
PORTASYSTEMIC SHUNT, TRANSJUGULAR INTRAHEPATIC
SWINE
THROMBOSIS
TIME FACTORS
TUNICA INTIMA
ULTRASONOGRAPHY, INTERVENTIONAL
VASCULAR PATENCY
VENA CAVA, INFERIOR