Journal of Invasive Cardiology

In patients with ST-segment elevation acute myocardial infarction (AMI), several studies have examined the role of glycoprotein (GP) IIb/IIIa receptor inhibition as adjunctive pharmacotherapy for percutaneous coronary intervention (PCI) and as part of a combined fibrinolytic/antiplatelet regimen. In the ReoPro and Primary PTCA Organization and Randomized Trial (RAPPORT), the use of abciximab as adjunctive therapy during primary angioplasty for AMI reduced the composite endpoint of death, recurrent MI and urgent revascularization at 30 days by approximately 50% compared with controls (5.8% versus 11.2%, respectively; p = 0.03).¹ Then, the Intracoronary Stenting and Antithrombotic Regimen (ISAR-2) trial demonstrated a similar reduction with abciximab in the composite endpoint of death, recurrent MI and urgent revascularization at 30 days in patients undergoing primary stenting (5.0% versus 10.5%, respectively; p = 0.038).² The Abciximab Before Direct Angioplasty and Stenting in Myocardial Infarction Regarding Acute and Long-term Follow-up (ADMIRAL) trial, which also examined abciximab as an adjunct to stenting, demonstrated a 59% reduction at 30 days in the composite endpoint of death, recurrent MI or urgent target vessel revascularization (TVR) with abciximab compared with placebo in a high-risk population of patients (6.0% versus 14.6%, respectively; p = 0.01).³

Furthermore, the Stent Versus Thrombolysis for Occluded Coronary Arteries in Patients with Acute Myocardial Infarction (STOP-AMI) investigators demonstrated that stenting with abciximab was associated with improved recovery of microvascular function, reduced infarct size, better preservation of left ventricular (LV) function and a significant survival benefit compared to fibrinolysis with alteplase.⁴

Three small angiographic studies have assessed the effect of abciximab alone on restoring infarct vessel patency during AMI. In the Glycoprotein Receptor Antagonist Patency Evaluation (GRAPE) trial,⁵ a Thrombolysis in Myocardial Infarction (TIMI) 3 flow rate of 18% was achieved with abciximab at a mean of 45 minutes. Similar improvements in TIMI flow were observed in the abciximab-only arms of the Strategies for Patency Enhancement in the Emergency Department (SPEED) trial (TIMI 3 flow in 27% of patients at 60–90 minutes) and TIMI-14 (TIMI 3 flow in 32% of patients at 90 minutes) trials.^6,7

The initial experience with GP IIb/IIIa antagonists suggests the potential for improved vessel patency when these agents are combined with full-dose fibrinolytic therapy. Abciximab, given soon after full-dose alteplase in the Thrombolysis and Angioplasty in Myocardial Infarction (TAMI-8) study, was associated with a pre-discharge infarct patency rate of 92% compared with 56% in controls, bleeding rates comparable to those in control patients and a reduction in recurrent ischemia.⁸