[Reaction between blood and heparin immobilized on synthetic polymers]

The influence of heparin covalent immobilization on its biological functions was studied. In-vivo experiments with prosthetic vascular devices made from polyethyleneterephthalate modified with heparin demonstrated that after 6 months of implantation to dogs the prostheses maintain their functions without thrombus formation. Thromboelastography and coagulograms showed that the decrease in the overall coagulant activity of the blood and changes in the most parameters of the coagulation system take place as a result of blood contact with heparin-containing polymers. In the animal body the changes observed were found to be rapidly compensated for. On studying the interaction of immobilized heparin with plasma proteins it was discovered that fibrinogen, thrombin and fibrinolysin are actively bound by immobilized heparin, with the resulting products being active in lysis of non-stabilized fibrin.