Efficacy and Bleeding Complications Among Patients Randomized to Enoxaparin or Unfractionated Heparin for Antithrombin Therapy in Non–ST-Segment Elevation Acute Coronary Syndromes

UNSTABLE ANGINA AND NON– ST-segment elevation myocardial infarction (UA/ NSTEMI) acute coronary syndromes (ACS) are the most prominent and fastest growing manifestations of coronary heart disease and are the leading causes of death and cardiovascular morbidity in developed countries. While the use of antithrombin therapy has become a guidelinesrecommended standard of care in the treatment of ACS, the choice of agent remains a source of debate. Currently, the most commonly used therapies are unfractionated heparin and low-molecular-weight heparin; in the last decade, enoxaparin has emerged as the most commonly used form of lowmolecular-weight heparin. Author Affiliations and Financial Disclosures are listed at the end of this article. Corresponding Author: Kenneth W. Mahaffey, MD, Division of Cardiology, Department of Medicine, Duke Clinical Research Institute, 2400 Pratt St, Durham, NC 27715 ([email protected]). Context Antithrombin therapy has become a guidelines-recommended standard of care in the treatment of acute coronary syndromes (ACS), but recent trials comparing use of enoxaparin and unfractionated heparin in ACS have yielded less robust efficacy and safety results than have earlier trials of these antithrombin therapies.