The vascular prosthesis without pseudointima prepared by antithrombogenic phospholipid polymer

On the luminal surface of the common synthetic vascular prostheses, blood coagulation can occur and a thrombus membrane is formed when blood flow passes through it. The thrombus membrane should be organized according to the wound healing process and it becomes a pseudointima which could serve as a blood conduit. However, the small-diameter vascular prosthesis may be quickly occluded by the initial thrombus. Therefore, no clinically applicable small-diameter prostheses have been developed to date. 2-Methacryloyloxyethyl phosphorylcholine (MPC) polymers resemble the structure of an outer cell membrane similar to the fluid mosaic model and demonstrate excellent antithrombogenicity. The purpose of this study is to develop a clinically applicable small-diameter prosthesis based on the new concept of the MPC polymer. We prepared vascular prostheses (2 mm ID) from polymer blend composed of segmented polyurethane and the MPC polymer. The prostheses were placed in rabbit carotid arteries. The luminal surface retrieved at eight weeks after implantation was clear without thrombus and pseudointima. We now realize that the vascular prosthesis having the MPC polymer can be applied as a small-diameter prosthesis because it functions without thrombus and pseudointima formation.