[Antithrombin III control in patients with long-term anticoagulant therapy].

Antithrombin III and protein C are the major inhibitors of the plasma clotting system. Since adequate thromboembolism protection requires a cofactor AT III for heparin to provide full antithrombotic coverage, the preoperative AT III and protein C levels in the plasma of 105 patients treated with marcumar are measured. The understanding of the physiological role of these inhibitors of the plasma clotting system and of the causes for their decrease should directly lead to the indications for laboratory analysis.