Perivascular Endothelial Implants Inhibit Intimal Hyperplasia in a Model of Arteriovenous Fistulae: A Safety and Efficacy Study in the Pig

Vascular access complications are a major problem in hemodialysis patients. Native arteriovenous fistulae, historically the preferred mode of access, have a patency rate of only 60% at 1 year. The most common mode of failure is due to progressive stenosis at the anastomotic site. We have previously demonstrated that perivascular endothelial cell implants inhibit intimal thickening following acute balloon injury in pigs and now seek to determine if these implants provide a similar benefit in the chronic and more complex injury model of arteriovenous anastomoses. Side-to-side femoral artery-femoral vein anastomoses were created in 24 domestic swine and the toxicological, biological and immunological responses to allogeneic endothelial cell implants were investigated 3 days and 1 and 2 months postoperatively. The anastomoses were wrapped with polymer matrices containing confluent porcine aortic endothelial cells (PAE; n = 14) or control matrices without cells (n = 10). PAE implants significantly reduced intimal hyperplasia at the anastomotic sites compared to controls by 68% (p