Direct versus indirect thrombin inhibition in percutaneous coronary intervention.

Heparin has been used to prevent intravascular thrombosis and clotting on the surface of equipment used during percutaneous coronary interventions (PCI) since Andreas Gruentzig performed the first angioplasty. In fact, the development of coronary angioplasty and of coronary artery bypass surgery would probably not have been possible without heparin. However, with the availability of low molecular weight heparin (LMWH) and the approval of bivalirudin, a direct thrombin inhibitor for use during PCI, the question is more and more frequently asked whether heparin should be replaced in PCI. The purpose of this paper is to critically review the evidence for the use of heparins (indirect thrombin inhibitors) and direct thrombin inhibitors during PCI.