Chitosan/heparin sirolimus drug-eluting stent system improves anticoagulation and promotes early re-endothelialization in porcine coronary artery

Abstract

Objective To construct a sirolimus loaded drug-eluting stent(DES)using chitosan/heparin coating membrane and to explore its effect on anticoagulation and early re-endothelialization in porcine coronary artery.Methods Chitosan/heparin layer-by-layer self-assembly coating was applied to sirolimus DES,and the asymmetric applicator was used to allow for the stent blood surface to be chitosan/heparin coated and the stent vascular surface to be polylactic acid(PLA)-sirolimus.The experiment was divided into bare metal stent(BMS)group,chitosan/heparin stent group,sirolimus DES group and chitosan/heparin sirolimus DES group.The anticoagulation effect of chitosan/heparin sirolimus DES was tested by arteriovenous shunt model and high load thrombosis model.The effect of chitosan/heparin sirolimus DES on early reendothelialization was tested by 1-week long balloon injury to porcine coronary artery.Results No thrombus was found on the surfaces of chitosan/heparin sirolimus DES and chitosan/heparin stent in the arteriovenous shunt model,while the surfaces of BMS and sirolimus DES were covered with thrombus.No stent thrombosis was found in the high load thrombosis model test of chitosan/heparin sirolimus DES and chitosan/heparin stent within 6hours,and stent thrombosis was found in BMS at(59.0± 8.5)min and in sirolimus DES at(67.0±7.8)min(P0.01).The early re-endothelialization test showed endothelial coverage rates of chitosan/heparin sirolimus DES and chitosan/heparin stent after 7dimplantation were(82.7±16.4)% and(80.7±14.1)%, significantly higher than those of BMS and sirolimus DES([64.3±11]%and[59.8±8.4]%,respectively;P0.01).Conclusion Chitosan/heparin-coated-sirolimus DES has satisfactory anticoagulation property and it can accelerate early re-endothelialization.