Thrombogenicity of heparin and non-heparin bound arterial prostheses: an in vitro evaluation

The effect on graft thrombogenicity of binding heparin to the luminal surface of prosthetic arterial grafts was investigated. Venous blood was obtained from healthy volunteers and exposed for 30 minutes to tubular segments of standard knitted dacron, polytetrafluoroethylene (PTFE) and a recently introduced heparin-bound knitted dacron graft. After this exposure the fibrinogen level of each sample was measured. The median (range) fibrinogen levels (expressed as a percentage of that in unexposed blood samples) were: standard dacron 3.5% (0-5.4%); PTFE 95.5% (0-121.1%); and heparin-bound dacron 79.8% (3.8-109.6%). Fibrinogen levels in the standard dacron group were significantly less than that of the PTFE and heparin-bound dacron groups (P < 0.05). No significant difference was found between the fibrinogen levels of the PTFE and heparin-bound dacron groups (P = 0.35). These findings suggest that heparin binding significantly reduces fibrinogen consumption and hence may reduce graft thrombogenicity.