Summary
Heparin is known to affect platelet function in vitro, but little is known about the
effect of heparin on the interaction of platelets with polymer surfaces in general,
and vascular graft materials in particular. For this reason, the effect of heparin
vs. citrate anticoagulation on the interaction of platelets with the vascular graft
materials expanded polytetrafluoroethylene (ePTFE), Dacron Bionit (DB) and preclotted
Dacron Bionit (DB/PC) was studied in a recirculating, in vitro perfusion system. Platelet activation, as shown by a decrease in platelet count,
an increase in platelet release and a decrease in platelet aggregation, was observed
for all vascular graft materials tested using heparin and was greater for Dacron and
preclotted Dacron than for ePTFE. Significant differences between heparin and citrate
anticoagulation were seen for platelet release, platelet aggregation and the relative
ranking of material platelet-reactivity. However, the trends and time course of platelet
activation were similar with both heparin and citrate for the materials tested.
Key words
Platelet activation - Vascular grafts - Effect of anticoagulation - In vitro perfusion
system