Management of patients with acute coronary syndromes: what is the clinical role of direct thrombin inhibitors?

Despite important pharmacokinetic and biological advantages of direct thrombin inhibitors over heparin, early randomised trials failed to demonstrate a clear net clinical benefit of these agents compared with heparin because of a higher bleeding risk, particularly with hirudin, and only modest efficacy gains. More recently, however, a systematic review of the direct thrombin inhibitor trials based on individual patient data as well as the results of the 17 000-patient Hirulog Early Reperfusion or Occlusion (HERO)-2 trial have confirmed the superiority of both hirudin and bivalirudin over unfractionated heparin in patients with acute coronary syndromes and undergoing percutaneous coronary intervention. Ongoing trials should further clarify the role of bivalirudin in patients undergoing percutaneous coronary intervention in the context of glycoprotein IIb/IIIa inhibitor use, while additional studies are required to define the role of direct thrombin inhibitors used in conjunction with other newer antithrombotic and/or thrombolytic strategies in patients with acute coronary syndromes.