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 w as obtained from healthy volunteers and exposed for 30 minutes to tubu lar 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 me dian (range) fibrinogen levels (expressed as a percentage of that in u nexposed blood samples) vr ere: standard dacron 3.5% (0-5.4%); PTFE 95 .5% (0-121.1%); and heparin-bound dacron 79.8% (3.8-109.6%). Fibrinoge n levels in the standard dacron group were significantly less than tha t of the PTFE and heparin-bound dacron groups (P < 0.05). No significa nt difference was found between the fibrinogen levels of the PTFE and heparin-bound dacron groups (P = 0.35). These findings suggest that he parin binding significantly reduces fibrinogen consumption and hence m ay reduce graft thrombogenicity.