| Summary: | The development of novel biodegradable vascular grafts of a small diameter (<6 mm) is an unmet clinical need for patients requiring arterial replacement. Here we performed a pre-clinical study of new small-caliber biodegradable vascular grafts using a sheep model of carotid artery implantation. The 4 mm diameter vascular grafts were manufactured using a mix of polyhydroxybutyrate/valerate and polycaprolactone supplemented with growth factors VEGF, bFGF and SDF-1α (PHBV/PCL-GFmix) and additionally modified by a polymer hydrogel coating with incorporation of drugs heparin and iloprost (PHBV/PCL-GFmix<sup>Hep/Ilo</sup>). Animals with carotid artery autograft implantation and those implanted with clinically used GORE-TEX<sup>®</sup> grafts were used as control groups. We observed that 24 h following surgery, animals with carotid artery autograft implantation showed 87.5% patency, while all the PHBV/PCL-GFmix and GORE-TEX<sup>®</sup> grafts displayed thrombosis. PHBV/PCL-GFmix<sup>Hep/Ilo</sup> grafts demonstrated 62.5% patency 24 h following surgery and it had remained at 50% 1 year post-operation. All the PHBV/PCL grafts completely degraded less than 1 year following surgery and were replaced by de novo vasculature without evidence of calcification. On the other hand, GORE-TEX<sup>®</sup> grafts displayed substantial amounts of calcium deposits throughout graft tissues. Thus, here we report a potential clinical usefulness of PHBV/PCL grafts upon their additional modification by growth factors and drugs to promote endothelialization and reduce thrombogenicity.
|
|---|