Coatings for small diameter blood vessel prosthetic materials, blood contacting materials, and other implantable medical devices and prosthetics.
Atherosclerosis continues to be a cause of morbidity and mortality despite advances in preventive measures and pharmacological therapeutics. Nearly 700,000 vascular surgical procedures are performed each year in the U.S. along with several hundred thousand peripheral and coronary angioplasties. Prosthetic bypass grafts and, more recently, arterial stents and other endovascular prosthesis have been utilized in association with these reconstructive procedures. Although large diameter grafts (at least 6 mm in diameter) have been successfully developed from polymers such as polytetrafluoroethylene and polyethylene terephthalate, the fabrication of a durable small diameter prosthesis (less than 6 mm internal diameter) remains unsolved. Thrombus formation and restenosis currently limit usefulness of small diameter grafts, and these complications require that the patient endure discomfort, health risks, and further medical treatment. Furthermore, while prosthetic bypass grafting can be performed in the infrainguinal position with reasonable short term success, within 5 years 30-60% of these grafts fail. Likewise, restenosis and/or occlusion occur in as many as half of all patients within 6 months of stent placement, depending on the site and the extent of the disease.
The control of thrombus formation on molecularly engineered surfaces is critical in the development of improved small diameter arterial prostheses for use in cardiac, plastic, and vascular surgery, as well as in the successful implantation of artificial organs and metabolic support systems. Emory researchers have developed a coating for small diameter blood vessel prosthetic materials, blood contacting materials and other implantable medical devices and prosthetics so that the performance of the prosthetic and other devices are less prone to thromboses and less likely to induce an inflammatory response in the patient in which the prosthesis or device has been installed. The invention further provides stable antithrombogenic membrane mimetic surface assemblies in which thrombomodulin, a truncated thrombomodulin and/or endothelial protein C receptor has been incorporated into a lipid assembly.