ACUTE CARDIAC CARE zyxwvu 07494704/01 $15.00 + .OO ANTITHROMBOTIC AND THROMBOLYTIC THERAPY IN ACUTE CARDIAC CARE Rohit Sundrani, MD, and Lloyd W. Klein, MD The acute coronary syndromes (including unstable angina and non-ST-elevation myocardial infarction) and ST-elevation myocardial infarction17are related pathogenetically, because each represents a differ- ent stage of plaque rupture and thrombosis.M, zyx 45 These entities involve the coagulation cascade at different levels and intensities. Hence, anti- thrombotic therapy plays a major role in the management of acute coronary syndromes. In most patients presenting with acute coronary syndromes, the thrombus is only partially occlusive. Antithrombotic agents maintain vessel patency by preventing the progression of a nonocclusive thrombus to an occlusive thrombus and by inhibiting the generation of new thrombi. In contrast, the infarct-related artery in most patients with ST- segment elevation is occluded completely by thrombus. Therefore, the first goal in these patients is to achieve rapid reperfusion by mechanical dissolution of thrombus or administration of thrombolytic therapy. Sec- ond, it is important to maintain patency of the infarct-related artery to prevent recurrent thrombosis leading to reocclusion and recurrent ische- mia. This maintenance is accomplished by anticoagulant and antiplate- let therapy. Recent multicenter clinical trials have led to the introduction of new antithrombotic agents in the management of acute coronary syndromes. These include platelet glycoprotein Ilb/IIIa (GP IIb/IIIa) receptor inhibi- tors, low molecular weight heparins (LMwHs), and direct thrombin in- From the Rush Heart Institute, Rush-Presbyterian-St. Luke's Medical Center, Chicago, Illi- nois CRITICAL CARE CLINICS VOLUME zyxwvuts 17 * zyxwvutsrqp NUMBER zyxwvutsrq 2 * APRIL 2001 379