Parenteral Anticoagulant Agents in PCI

Unfractionated heparin (UFH) has been the mainstay of anticoagulation in ischemic coronary disease for over a quarter of a century. This chapter examines the data on the use of available anticoagulants in the setting of percutaneous coronary intervention (PCI) for the different clinical presentations of coronary artery disease (CAD), and makes summary recommendations for best clinical practice. Heparin functions as an indirect thrombin inhibitor, exerting its effects through the endogenous serine protease antithrombin (AT) III. Thrombocytopenia is often associated with thrombotic and rarely with hemorrhagic complications. Low molecular weight heparin is produced through the enzymatic or chemical degradation of UFH. Direct thrombin inhibitors (DTI) are small molecules that can bind and inactivate both circulating and clot-bound thrombin. Argatroban is a small, monovalent DTI that binds reversibly to thrombin. Factor Xa inhibitors are the most refined and lowest molecular weight heparin. They contain a pentasaccharide sequence that specifically binds factor Xa.