The Porcine Hemodialysis Access Model

Adenovirus-Mediated Expression of β-Adrenergic Receptor Kinase C-Terminus Reduces Intimal Hyperplasia and Luminal Stenosis of Arteriovenous Polytetrafluoroethylene Grafts in Pigs

“…As previously reported, 23,25 the majority of intimal hyperplasia in the pig model occurred at the graft/vein anastomosis, whereas minimal neointimal lesions were observed in the upstream and downstream vein segments. It has been suggested that neointimal lesions in the upstream and downstream vein may occur more frequently if the PTFE graft is maintained for longer than 28 days.…”

“…More importantly, the histological lesions of venous neointimal hyperplasia in pigs are very similar to those in human PTFE dialysis grafts. 23,25 In the present study, we observed extensive formation of neointima composed of smooth muscle cells, myofibroblasts, inflammatory cells, and microvessels at the graft/vein anastomosis. Moreover, there was neointimal overgrowth into the graft lumen.…”

“…23,25 The size and histological structure of the pig vessels are similar to those of humans. More importantly, the histological lesions of venous neointimal hyperplasia in pigs are very similar to those in human PTFE dialysis grafts.…”

“…It has been suggested that neointimal lesions in the upstream and downstream vein may occur more frequently if the PTFE graft is maintained for longer than 28 days. 23,25 In addition, the animals did not have uremia and were not subjected to dialysis, which was different from patients who undergo dialysis. Despite these differences, the marked similarities between pig and human neointimal lesions indicate that this pig model is clinically relevant to human PTFE graft failure.…”

“…The percentage of stenosis was calculated as the minimal luminal diameter of the graft at the anastomosis site divided by the luminal diameter of the most adjacent point of the normal vein segment (downstream of the anastomosis and proximal to the heart) that showed no angiographic narrowing. 23 …”