Treatment of experimental saccular aneurysms of carotid arteries with three kinds of covered stents in canine models / 介入放射学杂志

ABSTRACT

Objective To assess the effectiveness and safety and biocompatibility of balloon-expanding stainless steel stents (SSS) covered with polyurethane membrane (PUM), expanding poly teflon ester membrane(ePTFEM)and biomembrane (BM) in the treatment of experimental saccular aneurysms of carotid arteries in canine models.Methods 36 experimental saccular aneurysms of carotid arteries in 20 canines were created successfully by sugery. Experimental aneurysms were treated with covered stents including twelve PUM-SSS, twelve ePTFEM-SSS and twelve BM-SSS for each twelve canines repectively. They were placed endovascularly in the common carotid arteries covering the orifice of aneurysms. Follow up angiography was performed immediately after the procedure and 2, 4 and 12 weeks afterwards under the control of conventional anticoagulation. The animals were then sacrificed for histopathologic and statistical investigation. Results 36 stents were placed successfully in the target arteries. The complete patency rates of PUM-SSS, ePTFEM-SSS and BM-SSS were 25.0%, 41.7% and 91.7% respectively. Histological analysis indicated that all treated aneurysmal pouches were filled with thrombus. Stent wires were found to be located deep within the vessel wall and encased by extension of the tunica intima. Endothelialization of BM-SSS groups already began at the 2nd week which was earlier than that of PUM-SSS and ePTFEM-SSS. Various degrees of degenerative cells were seen under the transmission electron microscopy without surface erosion of stents. Conclusion Placement of covered stent endovascularly is expedient, safe, and effective. BM-SSS provides the best mechanical behavior, physiochemical stability, anticoagulative ability and biocompatibility.