In vitro endothelialization of PEtU/PDMS vascular prosthesis: from the raw to the endothelial cell lined graft using a new designed bioreactor

Treatment of obstructive atherosclerosis disease, which is a major cause of mortality in the western world, may involve replacement or by-passing of affected arteries using synthetic vascular grafts. Whereas synthetic vascular grafts have been used successfully to replace large-diameter blood vessels, the long-term patency of small-diameter vascular grafts (<= 6 mm) is still disappointing. The primary failure modes of synthetic small diameter grafts are thrombus formation in the short term, due to thrombogenicity of the blood contacting synthetic surface, and intimal hyperplasia in the longer term, mainly attributed to compliance mismatch between the elastic artery and the relatively inelastic prosthetic graft. One of the most promising approaches to improve the blood compatibility of these grafts is to cover the luminal surface with endothelial cells (ECs), whereas the compliance mismatch can be solved in part by using grafts with elastic properties similar to native arteries. The aim of this study was to find optimal conditions for the in vitro endothelialization of small-diameter vascular grafts realised with a new synthesized silicone based poly(ether)urethane material (PEtU/PDMS).