Novel electrospun polyurethane grafts for vascular access in rats

Objectives: The purpose of this study is to develop a new and improved polyurethane (PU) graft using electrospinning and chemical modifications for hemodialysis patients, which will replace the current standard, polytetrafluoroethylene (PTFE) graft. The chemical modifications aim to improve hemocompatibility and reduce thrombogenicity and neointimal hyperplasia. Method: The study population was randomized and divided equally into four groups; one control group received a PTFE graft, and three treatment groups received three different types of polyurethane grafts. Two duplex measurements were performed directly on the graft on the same locations, followed by a histologic examination. Results: In the first few days after the implantation animals lost some weight, it took a week to recover to pre-surgical weight. Throughout the 28 days, there was no significant difference between animals in wound, activity, and the general appearance. PTFE and PU A groups have lower compliance or reduced graft diameter due to neointimal hyperplasia development on Doppler interrogation. The histological analysis showed limited neointimal hyperplasia development and no excessive inflammatory response to any of the grafts.