Abstract
Antithrombotic activity of low molecular weight heparins (LMWH) in subcutaneous application creates antithrombotic environment by several mechanisms:binds significantly to antithrombin,thus inhibits factor Xa more selectively;increases fibrinolysis;decreases a plasminogen activator inhibitor;increases tissue factor inhibitor,thus inhibits tissue factor and extrinsic coagulation system.LMWH are standardized according to the inhibition act. of factor Xa.However,preparations with higher anti Xa activity dont have demonstrably greater antithrombotic effect.In comparison to an unfractionated heparin it is used with an advantage in transplant medicine,in a treatment and prevention of vascular occlusions in tumours,in patients with thromboembolisms in cerebral area,in a prophylaxis and treatment of deep vein thrombosis in patients with ischaemic heart disease.LMWH expressly blocks a receptor of smooth muscle fibres thus interferes with their proliferation,which is used in patients following cor. angioplasty.