New anticoagulant options for ST-elevation myocardial infarction and unstable angina pectoris/non-ST-elevation myocardial infarction.

In addition to antiplatelet therapy with aspirin, anticoagulation therapy with unfractionated heparin decreases the risk of myocardial infarction and death in patients with acute coronary syndromes. However, unfractionated heparin has pharmacologic limitations that limit efficacy and safety. Enoxaparin, fondaparinux, and bivalirudin are new anticoagulant therapy options with either superior efficacy or better safety than unfractionated heparin. Compared with unfractionated heparin, enoxaparin and fondaparinux are easier to administer, do not require monitoring, and facilitate longer treatment duration. Bivalirudin offers advantages for patients undergoing early percutaneous revascularization. Careful attention to dosing and excellent vascular access site management after cardiac catheterization are required to decrease the risk of bleeding and blood transfusion, which have been associated with increased mortality risk.