title: Reduced thrombogenic characteristics of expanded polytetrafluoroethylene and polyurethane arterial grafts after heparin bonding.
abstract: The effect of bonding of heparin, via a glutaraldehyde-stabilized ionic complex, on the early thrombogenicity of polyurethane (PU) and expanded polytetrafluoroethylene (PTFE) (Gore-tex) as well as covalent bonding of heparin on PTFE was studied in vivo. Grafts 6 cm long and 4 mm in diameter were placed in the carotid arteries of sheep and perfused for 4 hours at 25 ml/min in order to accelerate thrombus formation. The thrombogenicity was determined by calculation of the percent of the luminal surface free of thrombus and patency. In addition, 32P-labelled platelet accumulation was determined in some of the grafts. The stabilized ionic bonding of heparin significantly reduced the early thrombogenicity of PU but had little effect on PTFE grafts; but the thrombogenicity of the latter was markedly decreased following covalent bonding of heparin. A regional distribution of platelet accumulation was found with the distal anastomoses showing the highest platelet deposition. By choice of an appropriate method of heparinization, a significant reduction of the thrombogenicity of PU and PTFE grafts was achieved.
mesh_terms: D000818:Animals; D001807:Blood Vessel Prosthesis; D002339:Carotid Arteries / Q000601:surgery; D002341:Carotid Artery Thrombosis / Q000517:prevention & control; D005260:Female; D006493:Heparin / Q000627:therapeutic use*; D007553:Isotope Labeling; D008297:Male; D010761:Phosphorus Radioisotopes; D010976:Platelet Count; D011138:Polytetrafluoroethylene; D011140:Polyurethanes; D012756:Sheep; D013927:Thrombosis / Q000517:prevention & control*
chemical_list: D010761:Phosphorus Radioisotopes; D011140:Polyurethanes; D011138:Polytetrafluoroethylene; D006493:Heparin