Monitoring heparin in patients with a lupus anticoagulant: detection of heparin resistance.

摘要

Antiphospholipid syndrome (APS) is the association of anti-phospholipid antibodies with arterial and/or venous thrombo-embolism and/or pregnancy morbidity [1]. The antibody is detected either by detecting lupus anticoagulant (LA) or using enzyme-linked immunosorbent assay assays to detect anticard-iolipin and beta2-gylcoprotein antibodies, present on at least two occasions more than 12 weeks apart [1]. LA is the antiphosp-holiprd antibody that has been most closely associated with a thrombotic tendency [2]. Currently, many patients with previous thrombosis and antiphospholipid antibodies require long-term oral anticoagulation [3]; however, both unfractionated heparin (UFH) and low molecular weight heparin (LMWH) are used widely in these patients to cover perioperative thrombosis, for immediate treatment of an acute thrombotic event, to manage pregnancies with previous thrombosis and/or fetal loss, or during interventional cardiovascular procedures. We had noted that patients with LA undergoing cardiac surgery, where large doses of heparin are required to prevent clotting in the cardiopulmonary bypass circuit, had heterogeneous activated clotting time (ACT) results.