Heparin remains the most commonly used
anticoagulant in the treatment of patients with acute vascular syndromes, including
myocardial infarction,
unstable angina and
ischaemic stroke. However,
heparin therapy is not always associated with a significant improvement of clinical outcomes, is linked with enhanced
bleeding risk and can occasionally provoke the development of
heparin-induced thrombocytopaenia, the most devastating complication of conventional
therapy with unfractioned
heparin. Understanding the key role of
thrombin in clot formation and platelet activation has stimulated the development of a new class of drugs -
direct thrombin inhibitors. The
direct thrombin inhibitor argatroban has been known for decades. Similar to the unfractioned
heparin,
argatroban requires
intravenous administration and activated partial prothrombin time-dependent dose adjustment; however, this pharmacological agent has a relatively short half-life that broadens its safety margins, as well as its low antigenic potential due to the small molecular weight of the compound. The efficacy of
argatroban has been demonstrated among patients with
acute coronary syndromes and
stroke. However, this
drug is currently approved by the FDA only for the treatment of patients with
heparin-induced thrombocytopaenia. Indeed, in such patients,
argatroban significantly improves clinical outcomes, and is associated with reduced mortality. Further clinical studies are needed to present more clinical evidence necessary to broad the indication spectrum of this agent.