Superhydrophobic modification fails to improve the performance of small diameter expanded polytetrafluoroethylene vascular grafts

To determine whether superhydrophobic modification of small diameter expand ed polytetrafluoroethylene (ePTFE) vascular grafts improves the performance of these grafts, we assessed neointima formation and platelet deposition i n standard and superhydrophobic modified ePTFE grafts. Standard and superhy drophobic vascular grafts were implanted in the carotid arteries of two rab bits and two pigs. Furthermore, standard and superhydrophobic vascular patc hes were implanted in the carotid arteries of seven pigs. After 4 weeks of implantation all patches were removed and histomorphometri c data were analyzed. The early thrombotic effect of superhydrophobic modif ication was examined by quantifying platelet glycoprotein receptor IIIa dep osition onto each type of vascular graft after 15 min of in vitro circulati on with human blood. All superhydrophobic and standard ePTFE vascular grafts occluded 15 min to I h after implantation in both rabbit and pie carotid arteries. All implant ed patches remained patent and were completely covered by endothelium. Supe rhydrophobic modification of ePTFE vascular grafts did not lead to less neo intima formation and resulted in significantly more platelet deposition tha n did standard ePTFE vascular grafts. Thus. superhydrophobic modification does not improve the performance of sma ll diameter ePTFE vascular grafts. (C) 2001 Elsevier Science Ltd. All right s reserved.