Unfractionated heparin given during cardiopulmonary bypass is remarkably immunogenic, as 25% to 50% of postcardiac surgery patients develop heparin-dependent antibodies during the next 5 to 10 days. Sometimes, these antibodies strongly activate platelets and coagulation, thereby causing the prothrombotic disorder, heparin-induced thrombocytopenia. The risk of heparin-induced thrombocytopenia is...

Laboratory monitoring is widely recommended to measure the anticoagulant effect of unfractionated heparin and to adjust the dose to maintain levels in the target therapeutic range. The most widely used laboratory assay for monitoring unfractionated heparin therapy is the activated partial thromboplastin time (aPTT). A fixed therapeutic range for the aPTT of 1.5 to 2.5 times the control value ha...

BACKGROUND Unfractionated heparin is often used as adjunctive therapy with fibrinolysis in patients with ST-elevation myocardial infarction. We compared a low-molecular-weight heparin, enoxaparin, with unfractionated heparin for this purpose. METHODS We randomly assigned 20,506 patients with ST-elevation myocardial infarction who were scheduled to undergo fibrinolysis to receive enoxaparin th...

Osteoporosis is a well-recognized complication of long-term heparin use. However, the mechanisms by which heparin can influence bone metabolism are unclear. We report here that unfractionated heparin stimulates the process of bone resorption and that the low molecular weight heparins (LMWHs), enoxaparin, fragmin, logiparin, and ardeparin produce significantly less calcium loss than unfractionat...

HEPARIN, A GLYCOSAMINOGLYCAN OF VARYING POLYsaccharide units and molecular weights, has been shown to reduce ischemic events beyond that of aspirin alone in the setting of an acute coronary syndrome (ACS). This benefit translated into a class I indication for unfractionated heparin in the 2000 American College of Cardiology/American Heart Association (ACC/ AHA) treatment guidelines for non–ST-s...

OBJECTIVE To evaluate the efficacy and safety of two subcutaneous prophylactic regimens for postoperative deep vein thrombosis after total hip replacement. DESIGN Prospective open randomised multicentre trial. SETTING 28 European departments of orthopaedic surgery. INTERVENTION All patients had bilateral phlebography 10 days after surgery. 31 patients receiving low molecular weight hepari...

CONTEXT When unfractionated heparin is used to treat acute venous thromboembolism, it is usually administered by intravenous infusion with coagulation monitoring, which requires hospitalization. However, subcutaneous administration of fixed-dose, weight-adjusted, unfractionated heparin may be suitable for inpatient and outpatient treatment of venous thromboembolism. OBJECTIVE To determine if ...

Current guidelines recommend using bivalirudin as an alternative to unfractionated heparin in patients with heparin-induced thrombocytopenia undergoing percutaneous coronary intervention (PCI). Pulmonary vein isolation (PVI) is a well-established treatment strategy for patients with drug-refractory atrial fibrillation (AF) and requires systemic anticoagulation to avoid thromboembolic events, ge...

Osteoporosis is a well-recognized complication of long-term heparin use. However, the mechanisms by which heparin can influence bone metabolism are unclear. We report here that unfractionated heparin stimulates the process of bone resorption and that the low molecular weight heparins (LMWHs), enoxaparin, fragmin, logiparin, and ardeparin produce significantly less calcium loss than unfractionat...

BACKGROUND The clinical benefits of heparin reach beyond its anticoagulative properties. Recently, it has been described that leukocytes adhere on immobilized heparin mediated by the integrin Mac-1 (CD11b/CD18, alphaMbeta2, or CR3). Because inhibition of this versatile adhesion molecule could explain various aspects of the beneficial clinical effects of heparin, we evaluated whether soluble hep...