A Case of Venous Neointimal Hyperplasia in the Mid-portion of a Polytetrafluoroethylene Dialysis Graft: Case Report

Arteriovenous grafts are used in end-stage renal disease patients who are not candidates for autologous arterioveinous fistula creation due to lower patency rates. Graft neointimal hyperplasia at the anastomotic site leads to graft thrombosis and failure. There are two theories when it comes to the initiating factors that lead to venous intimal hyperplasia at the graft vein anastomosis site. The widely accepted theory is that low shear stress caused by turbulence and compliance mismatch alters smooth muscle cells leading to venous hyperplasia at the anastomotic site. The alternative theory is that of Roy-Chaudhury et al who state that polytetrafluoroethylene (PFTE) graft functions as a foreign body and repeated punctures during dialysis attracts activated macrophages to the site of the lesion. These activated macrophages then produce cytokines, which cause smooth muscle cell proliferation and lead to venous intimal hyperplasia at the anastomotic sites2. We present a case of neointimal hyperplasia within the mid-portion of an AVG leading to graft thrombosis.