PHOSPHORYLCHOLINE COATING OF EPTFE REDUCES PLATELET DEPOSITION AND NEOINTIMAL HYPERPLASIA IN ARTERIOVENOUS GRAFTS

In an attempt to reduce platelet deposition and inhibit neointimal hyp erplasia, we evaluated the effect of coating expanded polytetrafluoroe thylene (ePTFE) grafts with phosphorylcholine (PC), a lipid found in a nimal cell membranes, in a dog model of femoral arteriovenous (AV) gra fts. Eight mongrel dogs underwent placement of a PC-coated femoral AV graft on one side and an untreated control graft on the contralateral side, Platelet deposition was measured by autologous (111)Indium-label ing and scintillation camera imaging analysis, Platelet deposition on the PC-coated grafts at 30 and 90 min. was 9.32 +/- 4.35 x 10(9) and 1 0.00 +/- 4.38 x 10(9), respectively, as compared with 10.26 +/- 4.36 x 10(9) and 11.64 +/- 5.08 x 10(9) platelet deposition on control graft s (P < 0.05). All grafts were patent at 4 weeks. There was a significa nt reduction of neointimal area at both arterial (0.07 +/- 0.05 mm(2)) and venous (0.18 +/- 0.09 mm(2)) anastomoses in the treated grafts as compared with arterial (0.15 +/- 0.05 mm(2)) and venous (0.43 +/- 0.2 2 mm(2)) anastomoses in the control grafts (P < 0.05). In addition, ne ointimal cell proliferation assayed by bromodeoxyuridine (BrdU) incorp oration was reduced in both arterial (2.05 +/- 0.81%) and venous (3.25 +/- 0.17%) anastomoses of treated grafts compared with arterial (3.12 +/- 1.23%) and venous (5.36 +/- 1.18%) anastomoses of control grafts (P < 0.05). These data demonstrated that PC coating of ePTFE grafts si gnificantly reduced platelet deposition, anastomotic neointimal hyperp lasia, and neointimal cell proliferation in a dog model of AV grafts, This may represent a new strategy for prolonging hemodialysis graft pa tency. (C) 1998 Academic Press.