Experimental research of covered stent implanted in canine hepatic artery

Objective: To evaluate the feasibility of success rate of implantation, post-procedure stenosis rate, apposition ability and endothelialization level, etc. for implantation with balloon-expandable covered stent in canine hepatic artery. Methods: 8 adult canines were implanted with balloon-expendable stents covered by expandable poly Teflon ester membrane (e-PTFEM). Follow-up DSA was performed immediately, 2, 4 and 12 wk after the procedure. The canines were sacrificed for histopathologic examination and statistical analysis with correlation of implantation manenvor and angiographic manifestations. Results: 8 cases were all implanted with the covered stents in proper hepatic artery/right hepatic artery successfully; showing good apposition ability and non-opacification of the separated branches. 2 cases showed intraluminal obvious stenosis( > 50%)of the stent at 2 weeks follow-up, so did 3 cases at 12 weeks follow-up, and the total stenosis rate was 37.5% and 5 cases manifested full endothelialization (3 different locations of the sample all manifested full endothelialization), 3 cased manifested partial endothelialization (at least 1 location of the sample didn't show full endothelialization), and the two terminal parts were easier to get endothelialization than the central part. Before and after the stent implantation, hepatic function of all cases didn't demonstrate any obvious changes. Conclusions: Balloon-expandable covered stent can be implanted in canine hepatic artery. successfully, with good apposition ability, full endothelialization, and no influence on hepatic function. (authors)