Abstract:

BACKGROUND: Endothelialization is the aim of preventing restenosis in intravascular stent and transjugular intrahepatic portosystemic shunt (TIPS) stent. It has been suggested that promoting the recovery of function and integrality of endothelial cells is a new strategy for preventing restenosis after the operations.
OBJECTIVE: To investigate the efficacy of endothelialization of the shunts in TIPS by stents covered with small intestinal submucosa (SIS).
METHODS: TIPSS porcine models were established, and the porcine were randomly divided into two groups. In the experimental group monofilament braided nitinol stents covered with SIS were implanted into the shunts. In the control group monofilament braided nitinol naked stents were used. After direct portal phlebography at 2 and 4 week spostoperatively, the shunt and the surrounding hepatic tissues were harvested for macroscopical and microscopical observation by scanning election microscope (SEM).
RESULTS AND CONCLUSION: According to the portal venography 2 weeks after TIPS, 3 and 1 shunts were respectively occluded in control and experimental groups; 4 weeks after TIPS, 4 and 6 shunts were occluded in control and experimental groups, respectively, and the remainders of the shunts exhibited restenosis in different degrees. The restenosis rate was statistically greater in control group than the experimental group (P < 0.05). According to the microscopical observation and SEM, compared to the control group, more endothelialization occurred in the shunts of experimental group. Morphous and size of the endotheliocyte in the experimental group was well-distributed and arranging approach the direction of blood flow. Results show that SIS is a feasible biological material which can speed up the endothelialization of the shunts of TIPS, but the stents covered with SIS cannot improve the patency rate of the shunts efficiently.