The use of glycoprotein IIb/IIIa inhibitor therapy in acute ST-segment elevation myocardial infarction: current practice and future trends

Abstract

The goal of therapy in acute myocardial infarction is complete and timely restoration of coronary blood flow. Current strategies for reperfusion fail to achieve ideal results and resolution of ischemia in all patients. The platelet plays a pivotal role in the pathophysiology of an acute myocardial infarction, and antiplatelet therapy has been shown to improve clinical outcomes. The final common pathway for platelet activation and aggregation in acute myocardial infarction is the activation of the glycoprotein (GP) IIb/IIIa receptor. Newer reperfusion strategies target the GP IIb/IIIa receptor, thereby preventing the prothrombotic effects of platelets in an acute myocardial infarction. In the past decade, several strategies targeting the use of GP IIb/IIIa inhibitors have been evaluated. GP IIb/IIIa inhibitors have been shown to improve angiographic Thrombolysis in Myocardial Infarction (TIMI) 3 flow rates when used as reperfusion therapy given with heparin and aspirin as compared with heparin and aspirin alone. When GP IIb/IIIa inhibitors are used with full-dose fibrinolytics, early studies have suggested a trend toward more rapid and more complete reperfusion in an acute myocardial infarction. Later trials have examined the use of GP IIb/IIIa inhibitors in conjunction with reduced-dose fibrinolytics. Results from TIMI 14 and Global Use of Strategies to Open occluded arteries-IV pilot trials support the use of combination therapy with reduced- dose fibrinolytics and the GP IIb/IIIa inhibitor abciximab. Given the promising role of GP IIb/IIIa inhibitor therapy in acute myocardial infarction, investigators questioned the need for concomitant antithrombin therapy. However, data from several investigations suggest that antithrombin therapy is required when GP IIb/IIIa inhibitors are used with fibrinolytics, although it appears that the dose of heparin may be reduced. Finally, recent investigations have addressed the safety and efficacy of facilitated early percutaneous intervention. In this strategy, patients presenting with an acute myocardial infarction are treated with reduced-dose fibrinolytics and GP IIb/IIIa inhibitors and are taken to the interventional cardiac catheterization laboratory within the first 60 minutes of therapy.