Update on Glycoprotein IIb/IIIa Blockade in Endovascular Interventions

Platelet aggregation plays a central role in the ischemic complications of percutaneous coronary interventions (PCI) and the acute coronary syndromes (ACS). Although aspirin and heparin have been effective at decreasing adverse events in these settings, the perceived need for more potent inhibition of platelet aggregation has led to targeting of the platelet surface membrane glycoprotein IIb/IIIa (GP IIb/IIIa) receptor. Several agents have been developed; four: abciximab, tirofiban, eptifibatide, and lamifiban have been tested in clinical trials. Overall, the positive findings of these studies have supported the hypothesis that enhanced platelet blockade leads to improved clinical outcomes in the settings of PCI and ACS. In this article, an overview of the various GP IIb/IIIa receptor inhibitors is presented. The clinical trials of these agents as adjunctive therapy for patients undergoing PCI and in treatment of acute myocardial infarction are reviewed. Practical considerations relating to clinical efficacy, drug safety, and economic issues are discussed.     

GP IIb/IIIa inhibitors during primary percutaneous coronary intervention for STEMI: New trial and registry data

Primary percutaneous coronary intervention (PCI) with adjunctive glycoprotein (GP) IIb/IIIa receptor inhibitor therapy administered in the cardiac catheterization laboratory is the optimal reperfusion strategy for patients with ST-elevation myocardial infarction. Most available data regarding these agents are from trials comparing abciximab to placebo alone. Noninferiority trials comparing small-molecule GP IIb/IIIa receptor inhibitors, such as tirofiban and eptifibatide with abciximab, have used markers for myocardial reperfusion as primary end points but are underpowered to detect significant differences in hard clinical outcomes. Such a trial would need to enroll a very large number of patients and thus make it practically impossible to perform. Registry data reveal that most patients undergoing primary PCI are treated with small-molecule GP IIb/IIIa receptor inhibitors in clinical practice, and no observed difference is observed in safety and efficacy when compared with patients treated with abciximab therapy.     

Bleeding risk of platelet glycoprotein IIb/IIIa receptor antagonists in broad-based practice (results from the Society for Cardiac Angiography and Interventions Registry)

Randomized trials of platelet glycoprotein (GP) IIb/IIIa receptor inhibitors in patients who have undergone percutaneous coronary intervention (PCI) have shown a modest increase in bleeding risk associated with GP IIb/IIIa inhibitor use. Because clinical trials often enroll highly selected patient populations and are performed in high-volume experienced centers, these results may not apply to a nonclinical trial population, thus altering the risk-benefit ratio of the drugs. Given the widespread use of these agents, we sought to determine bleeding risks in a broad-based population of patients who underwent PCI. We performed a retrospective cohort study of GP IIb/IIIa inhibitors and bleeding in 18,821 procedures from June 1, 1996 to December 31, 1998 using the Society for Cardiac Angiography and Interventions Registry. The primary outcome was bleeding events, defined as clinically significant hematoma formation or hemorrhage. Bleeding risk was 1.9% in the 2,525 patients who received GP IIb/IIIa inhibitors compared with 1.0% in the 16,296 who did not (unadjusted odds ratio [OR] 1.87, 95% confidence interval [CI] 1.35 to 2.59, p <0.001). After adjustment for multiple clinical and procedural variables, the effect was attenuated, with at most a twofold bleeding risk associated with GP IIb/IIIa inhibitor use (adjusted OR 1.39, 95% CI 0.96 to 2.03, p = 0.083). The small increase in absolute risk of bleeding from GP IIb/IIIa inhibitor use in this study is similar to the risk observed in clinical trials. Assuming these agents are as effective as shown in these trials, the risk-benefit ratio of GP IIb/IIIa inhibitors in broad-based PCI practice should be favorable.     

Glycoprotein IIb/IIIa inhibition in the setting of acute ST-segment elevation myocardial infarction

Glycoprotein (GP) IIb/IIIa inhibitors have been extensively studied in the setting of percutaneous coronary intervention (PCI) and in the management of non-ST-segment elevation acute coronary syndromes. However, the use of GP IIb/IIIa inhibitors is less well established in the setting of acute ST-segment elevation myocardial infarction (MI). Multiple nonrandomized studies suggest that combination therapy with GP IIb/IIIa inhibitors and thrombolytic agents leads to increased rates of TIMI 3 flow. However, two clinical trials involving over 22,000 patients demonstrated that combination therapy is associated with only modest reductions in major adverse cardiac events, does not reduce mortality, and is associated with an increase in bleeding. In the setting of primary PCI, four clinical trials involving over 3,000 patients demonstrated that GP IIb/IIIa inhibition results in a significant decrease in the need for urgent target vessel revascularization but not in reductions of death or recurrent MI. Thus, GP IIb/IIIa inhibition may provide only limited benefits in the setting of acute ST-segment elevation MI.     

A propensity analysis of the impact of platelet glycoprotein IIb/IIIa inhibitor therapy on in-hospital outcomes after percutaneous coronary intervention

It is unknown whether the benefits of parenteral platelet glycoprotein (GP) IIb/IIIa inhibitors as an adjunct to percutaneous coronary intervention (PCI) demonstrated in randomized clinical trials extend to patients treated outside the setting of clinical trials. A contemporary registry of 10,847 consecutive PCI procedures was analyzed to determine the effect of GP IIb/IIIa inhibitor treatment on in-hospital major adverse coronary events ([MACEs] composite of death, urgent coronary artery bypass surgery, periprocedural myocardial infarction, abrupt closure, and stent thrombosis). In this registry, GP IIb/IIIa inhibitors were administered to 20.1% of patients. These patients were younger, more often men, and less often hypertensive than untreated patients. GP IIb/IIIa inhibitor-treated patients were more likely to present with acute myocardial infarction or unstable angina. Stents were placed in 79% of patients treated with GP IIb/IIIa inhibitors. MACEs occurred in 7.8% of GP IIb/IIIa inhibitor-treated patients compared with 3.8% of untreated patients (p <0.001). After multivariable adjustment for the propensity of GP IIb/IIIa inhibitor treatment as well as other possible confounders and interactions known to influence MACEs, GP IIb/IIIa inhibitor treatment was associated with a 57% increase in the risk of a MACE (odds ratio 1.57, 95% confidence interval 1.22 to 2.03; p = 0.0004). In a data set consisting of patients with a high degree of acuity predominantly treated with stent placement, GP IIb/IIIa inhibitor treatment is associated with an increase in thrombotic complications of PCI.     

Timing of glycoprotein IIb/IIIa inhibitor use and outcomes among patients with non-ST-segment elevation myocardial infarction undergoing percutaneous coronary intervention (results from CRUSADE)

Although glycoprotein (GP) IIb/IIIa inhibitors are recommended for patients with unstable angina and non-ST-segment elevation myocardial infarction who undergo percutaneous coronary intervention (PCI), the American College of Cardiology/American Heart Association guidelines do not specify optimal timing for their initiation. We compared patient characteristics and clinical outcomes in 30,830 patients with non-ST-segment elevation myocardial infarction included in the CRUSADE initiative (January 2001 to December 2004) who underwent PCI with upstream (>1 hour before PCI) or periprocedural use of GP IIb/IIIa inhibitors. GP IIb/IIIa inhibitors were administered upstream in 43% of patients versus periprocedurally in 57%. Time from arrival to PCI was longer for patients who received GP IIb/IIIa inhibitors upstream (median 25.6 hours) compared with periprocedurally (18.2 hours). Unadjusted incidence of in-hospital death or reinfarction was lower with upstream GP IIb/IIIa inhibitor use (3.8% vs 4.3%, p = 0.046), but after adjusting for patient and hospital characteristics, this difference was not statistically significant. Treatment with upstream GP IIb/IIIa inhibitors was associated with a lower incidence of unadjusted death or reinfarction in patients who underwent PCI <12 hours from hospital arrival. In conclusion, in this observational analysis, overall ischemic outcomes were similar between the 2 groups, but clinical trials are needed to solve the controversy over optional timing of GP IIb/IIIa inhibitor use.     

Use of Glycoprotein IIb/IIIa Inhibition Plus Fibrinolysis in Acute Myocardial Infarction

Pharmacological reperfusion therapy for acute myocardial infarction with intravenous fibrinolytic agents improves survival yet fails to achieve early and complete coronary blood flow in nearly half of treated patients. In principle, glycoprotein (GP) IIb/IIIa inhibitors, potent antiplatelet agents, might improve the efficacy and clinical outcomes associated with fibrinolysis. Preclinical research suggests more rapid and effective reperfusion with combined platelet GP IIb/IIIa inhibition and fibrinolysis. Early clinical studies confirm improved early patency and more rapid electrocardiographic resolution, but increased bleeding complications, with the addition of GP IIb/IIIa antagonists to conventional fibrinolysis. Future studies may combine reduced-dose fibrinolytic therapy with GP IIb/IIIa inhibition to optimize efficacy and safety.     

Synthetic inhibitors of platelet glycoprotein IIb/IIIa in clinical development

Activation of the platelet glycoprotein (GP IIb/IIIa) receptor on the platelet surface is the final pathway of platelet aggregation, regardless of the initiating stimulus. Inhibitors of GP IIb/IIIa receptors include monoclonal antibodies (abciximab) against this receptor and peptidic and nonpeptidic synthetic specific receptor blockers. Abciximab exchanges between and binds to platelets for as long as 2 weeks, whereas synthetic GP IIb/IIIa inhibitors inhibit ex vivo platelet aggregation for only a few hours after the end of infusion, but some have the advantage of also being orally active. In the secondary prevention of atherothrombosis, large-scale trials were successfully conducted with aspirin, dipyridamole, ticlopidine, and clopidogrel. In the first large-scale trials with GP IIb/IIIa inhibitors, abciximab was investigated. In aggregate, synthetic GP IIb/IIIa inhibitors, combined with aspirin and heparin, were shown to reduce ischemic events in patients with high- and low-risk coronary intervention, stents, unstable angina, and non-Q-wave infarction. With short-term use of synthetic GP IIb/IIIa inhibitors, there is no suppression of clinical evident restenosis 6 months after the end of treatment. With the doses currently used, bleeding occurs more often with the synthetic GP IIb/IIIa inhibitors (used for 3 days) than with abciximab (used for 12 hours), but there are no direct comparisons between these drugs.     

Small peptide GP IIb/IIIa receptor inhibitors as upstream therapy in non-ST-segment elevation acute coronary syndromes: results of the PURSUIT, PRISM, PRISM-PLUS, TACTICS, and PARAGON trials.

The primary pathophysiologic mechanism underlying all non-ST-segment elevation acute coronary syndromes (NSTE ACS) is the formation of platelet-rich coronary thrombi in response to spontaneous or intervention-induced endothelial damage with exposure of subendothelial substrates. Antagonists of the glycoprotein (GP) IIb/IIIa receptor ameliorate this process by blocking the final common pathway for platelet aggregation. Based upon collective data in over 24,000 patients, clinical trials have demonstrated that treatment of NSTE ACS patients with GP IIb/IIIa agents results in an approximate 12% relative risk reduction in the incidence of death or myocardial infarction at 30 days. The magnitude of this clinical benefit is increased in patients who are troponin-positive and who are referred for early percutaneous intervention. Potential benefits of GP IIb/IIIa inhibitor use must be weighed against an increased risk of bleeding. Ongoing controversies exist concerning the relative efficacy of different GP IIb/IIIa antagonists, the accurate use of platelet function tests to define safe and efficacious drug dosing, the adjunctive use of additional anti-thrombotic agents, and the optimal timing of upstream therapy before diagnostic cardiac catheterization and revascularization.     

Prospective Use of Glycoprotein IIb/IIIa Receptor Blockers in the Emergency Department Setting

Platelets play a pivotal role in the pathophysiology of acute coronary syndromes (ACS) and thus are logical therapeutic targets for treatment of this disease process. Platelet glycoprotein (GP) IIb/IIIa receptor antagonists, which interrupt the final common pathway of platelet aggregation, have been proved to reduce the 30-day incidence of death, acute myocardial infarction (MI), and urgent revascularization in both high-risk and low-risk patients undergoing percutaneous intervention procedures. Three-year follow-up has indicated that these benefits appear durable. Recent large-scale randomized trials have demonstrated the value of GP IIb/IIIa receptor inhibitors in reducing the risk of death and MI in patients with unstable angina or those with MI with non–Q-wave abnormalities who are receiving pharmacologic management. In addition, emerging evidence suggests a future role for GP IIb/IIIa receptor inhibitors as an adjunct to low-dose fibrinolytic therapy in patients with acute MI. As the list of indications for GP IIb/IIIa receptor antagonists expands to encompass the full spectrum of ACS, there is increasing interest in the potential use of these agents in the emergency department setting. The integration of GP IIb/IIIa receptor inhibitors into ED protocols will ultimately depend largely on whether these drugs prove to be safe and effective regardless of the direction of ST-segment deviation, and irrespective of whether definitive therapy will be invasive or conservative. [Gibler WB, Wilcox RG, Bode C, Castaigne AD, Delooz H, Elich D, Fox KAA, Kereiakes DJ, Rupprecht H, Topol EJ: Prospective use of glycoprotein IIb/IIIa receptor blockers in the emergency department setting. Ann Emerg Med December 1998;32:712-722.]     

Glycoprotein IIb/IIIa antagonists and low-molecular weight heparin in acute coronary syndromes.

The glycoprotein (GP) IIb/IIIa antagonists and the low-molecular weight heparins are the newest additions to the armamentarium of antiplatelet drugs for the treatment of acute coronary syndromes. They are extremely potent inhibitors of platelet aggregation and thrombin generation, respectively. There are currently three GP IIb/IIIa inhibitors (abciximab, eptifibatide, and tirofiban) and two low-molecular weight heparins (dalteparin and enoxaparin) approved for use with acute coronary syndromes. Data continue to accumulate outlining the specific roles for these drugs in the treatment of patients with acute coronary syndromes. Clinical trials in patients with acute coronary syndromes have demonstrated that the GP IIb/IIIa antagonists and low-molecular weight heparins offer significant benefit with acceptable safety profiles. Future issues that need to be addressed include refinement of indications for administration and patient selection, comparison between existing agents, evaluation of newer agents, and optimization of dosing to maximize benefit and safety in the use of these powerful new classes of drugs.     

Alveolar hemorrhage: an underdiagnosed complication of treatment with glycoprotein IIb/IIIa inhibitors

OBJECTIVE: Alveolar hemorrhage (AH) is a rare complication of treatment with GP IIb/IIIa inhibitors. Hemoptysis, a constant sign, lacks in specificity, and may occur in confounding syndromes such as pulmonary edema, pulmonary infarction, and pneumonia. Nonspecific symptoms and signs often delay the diagnosis, thereby allowing serious or even fatal disease progression. Here, we performed a large-scale retrospective analysis to define the incidence and risk factors of AH in the setting of GP IIb/IIIa inhibitors therapy. BACKGROUND: Randomized controlled trials demonstrate that treatment with glycoprotein IIb/IIIa (GP IIb/IIIa) inhibitors may improve the outcome of acute myocardial infarction (AMI) and angioplastic procedures. However, this treatment may rarely lead to severe hemorrhagic complications, in particular AH. Unfortunately, the incidence and risk factors of AH remain poorly defined. METHODS: We reviewed for the period extending from August 1998 to January 2005 consecutive histories of AMI patients receiving coronary arteriography and treatment with either eptifibatide or abciximab. Concomitantly admitted AMI patients not treated with GP IIb/IIIa inhibitors were reviewed and served as a control group. The diagnosis of AH required the demonstration of typical symptoms and signs including dyspnea, hemoptysis, arterial hypoxemia, pulmonary radiographic changes, and, when available, bronchoscopic signs for AH. Potential covariates including pulmonary disease, pulmonary hypertension, smoking, and use of other anticoagulant or antiplatelet agents were evaluated. RESULTS: Six of 1,810 patients (0.33%) receiving eptifibatide and five of 3,648 patients (0.14%) receiving abciximab exhibited typical symptoms and signs of AH. Contrarily, only one of 4,136 patients (0.025%) receiving no GP IIb/IIIa inhibitors presented with similar symptoms and signs. There was no fatal outcome, though two patients required blood transfusions. Statistically significant differences were found between control patients and patients receiving eptifibatide alone (P = 0.004). There was also a significant difference between untreated patients and those receiving eptifibatide and abciximab (P = 0.017). No differences were found between eptifibatide and abciximab-treated patients (P = 0.19) or between abciximab and untreated control patients (P = 0.105). CONCLUSIONS: AH is a rare complication of treatment with GP IIb/IIIa inhibitors. Its incidence ranged from 0.14% in patients treated with abciximab to 0.33% in those receiving eptifibatide. Compared to a control group, patients treated with GP IIb/IIIa inhibitors had a statistically increased risk for AH.     

Antiplatelet Strategies: Evaluating Their Current Role in the Setting of Acute Coronary Syndromes

Numerous clinical trials have established the value of antiplatelet therapies for acute coronary syndromes (ACS). Aspirin (ASA), thienopyridines (i.e., clopidogrel and ticlopidine) and GP IIb/IIIa antagonists comprise the major classes of antiplatelet therapies demonstrated to be of benefit in the treatment of ACS and for the prevention of thrombotic complications of percutaneous coronary intervention (PCI). Clopidogrel is beneficial when administered before and after PCI, and is more effective when combined with either ASA or GP IIb/IIIa inhibitors in preventing post‐PCI complications, coronary subacute stent thrombosis, and thrombotic events in general. It is currently unclear whether a higher loading dose of clopidogrel (600 mg) is better than the standard loading dose (300 mg), how long therapy should continue, and which maintenance dose is optimal. The role of the GP IIb/IIIa antagonists in ACS is less clear due to conflicting data from several studies with different patient populations. Currently, it appears that the use of GP IIb/IIIa antagonists might be most beneficial in high‐risk ACS patients scheduled to undergo PCI, who demonstrate non‐ST‐segment elevation myocardial infarction and elevated troponin levels. Copyright © 2008 Wiley Periodicals, Inc.     

Effectiveness of glycoprotein IIb/IIIa inhibitor use during primary coronary angioplasty: results of propensity analysis using the New York State Percutaneous Coronary Intervention Reporting System

Patients undergoing primary angioplasty in clinical practice experience a higher risk for adverse events than those enrolled in clinical trials. Whether glycoprotein (GP) IIb/IIIa inhibitor use during primary angioplasty is both safe and effective in real life is unknown. Therefore, we examined the pattern of GP IIb/IIIa use and its effectiveness in a large population-based cohort of 7,321 patients who underwent primary angioplasty in New York State. Propensity analysis was used to account for the nonrandomized use of GP IIb/IIIa inhibitors. Overall, 78.5% of patients who underwent primary angioplasty received GP IIb/IIIa inhibitors. In-hospital mortality was significantly lower with GP IIb/IIIa use (3% vs 6.2%, p <0.0001) after adjustment for both propensity score (odds ratio 0.57, 95% confidence interval 0.44 to 0.74, p <0.0001) and the combination of propensity score and clinical characteristics (odds ratio 0.63, 95% confidence interval 0.45 to 0.88, p = 0.006). Patients with older age and higher Mayo Clinic Risk Score (MCRS) received GP IIb/IIIa inhibitors less often. However, stratified analysis of patients with low to moderate risk (MCRS <12) versus high risk (>or=12) demonstrated that GP IIb/IIIa use lowered risk of mortality both in low- to moderate-risk (1.39% vs 3.23%, p <0.0001) and high-risk patients (16.15% vs 22.41%, p = 0.03). In conclusion, adjunct GP IIb/IIIa inhibitor use during primary angioplasty is effective and associated with improved in-hospital survival rates.     

Effect of Glycoprotein IIb/IIIa Inhibitors on the Individual Components of Composite Endpoints Used in Clinical Trials of Unstable Angina and Non–Q-Wave Myocardial Infarction

Inhibitors of the platelet glycoprotein (GP) IIb/IIIa receptor complex have recently been approved for the treatment of patients with unstable angina and non–Q-wave myocardial infarction (MI). We performed a meta-analysis to ascertain the effect of these agents on the individual endpoints of death, myocardial infarction, refractory ischemia, and major bleeding after 30 days of follow-up. Five randomized, placebo-controlled trials involving 17,255 patients were identified. The odds ratios for each of the endpoints in each trial were calculated and combined using a fixed-effects model. There was no significant reduction in death (OR, 0.87; 95% CI, 0.73–1.03; P = 0.1), myocardial infarction (OR, 0.91; 95% CI, 0.82–1.004; P = 0.06), or refractory ischemia (OR, 0.92; 95% CI, 0.78–1.1; P = 0.36) in patients treated with GP IIb/IIIa inhibitors. There was a significant increase in major bleeding following treatment with GP IIb/IIIa inhibitors (OR, 1.2; 95% CI, 1.06–1.4; P = 0.005). When used to treat unstable angina and non–Q-wave MI, this new class of agents appears to be associated with minimal clinical benefit and an increase in major bleeding complications.     

Anti-thrombotic, anti-platelet and fibrinolytic therapy: current management of acute myocardial infarction

Significant advances in the treatment of patients with acute myocardial infarction (MI) have been obtained in recent times. In particular, thrombolytic therapy has been shown to preserve ventricular function and improve survival in patients with acute MI. Therapies now include third-generation thrombolytic agents, percutaneous transluminal coronary angioplasty (PTCA) and intracoronary stenting, and new anti-thrombotic therapies including anti-platelet treatment with glycoprotein (GP) IIb/IIIa inhibition and direct anti-thrombin agents. This review will focus on the use of GP IIb/IIIa antagonists and thrombin inhibitors as adjunctive therapies to thrombolytic treatment of patients with acute MI.     

Glycoprotein IIb/IIIa receptor inhibitor-thrombolytic combination therapy for acute myocardial infarction

Over the past two decades, we have witnessed a large decrease in the death and complication rate of patients experiencing acute myocardial infarction (MI), due to our ability to restore blood flow to infarct-related arteries. Therapies include strategies to inhibit platelet function and induce fibrinolysis, and mechanical reperfusion with percutaneous intervention. Despite decreases in morbidity and mortality with thrombolytic therapy, reperfusion rates remain less than optimal. With standard fibrinolytic therapy in combination with aspirin, it is thought that thrombolyticinduced platelet activation may be an important reason for failure to induce perfusion, or maintain reperfusion in the infarct-related artery. In the past 10 years we have moved from platelet inhibition with aspirin to newer, more potent platelet inhibitors such as glycoprotein (GP) IIb/IIIa antagonists. Recent trials have evaluated the efficacy and safety of combining thrombolytic drugs with GP IIb/IIIa receptor antagonists. Future trends may use combination therapy as a part of a mechanical strategy, using these medications to induce early reperfusion as the patient is prepared for percutaneous intervention. This review summarizes recently published trials using combination thrombolytic and GP IIb/ IIIa receptor inhibitor therapy in the treatment of acute MI.     

Direct thrombin inhibitors in acute coronary syndrome patients undergoing percutaneous coronary intervention: special effects in selected patients?

Coronary thrombosis is a pivotal event in the pathogenesis ofacute coronary syndromes (ACS) as well as in the incidence ofthrombotic complications resulting from percutaneous coronaryinterventions (PCIs).¹ Platelet adhesion and aggregation atthe site of spontaneous or provoked plaque rupture is an importantcontributor of such intracoronary thrombus formation. As activationof the platelet glycoprotein (GP) IIb/IIIa receptor is the finalcommon pathway in the process leading to platelet aggregation,inhibitors of the platelet GP IIb/IIIa are potent agents toprevent progression to myocardial infarction (MI) and death.In a recent meta-analysis of six phase III randomized trials,which enrolled 31 402 ACS patients without ST-elevationwho were not scheduled for early PCI, GP IIb/IIIa inhibitorswere associated     

Platelet Glycoprotein IIb/IIIa Integrin Blockade in Coronary Artery Disease: Current State of the Art

Platelets have been shown to play an important role in the pathogenesis of atherosclerosis, acute coronary syndromes, and ischemic complications after percutaneous coronary intervention. Fibrinogen binding via platelet surface glycoprotein (GP) IIb/IIIa receptors constitutes the "final pathway" in platelet aggregation leading to thrombus formation. The GP IIb/IIIa receptor inhibitors, a new class of antiplatelet agents that have emerged in recent years, show great promise in reducing complications of coronary angioplasty and acute coronary syndromes. This review will examine the biology of platelet GP IIb/IIIa receptors, the various classes of GP IIb/IIIa receptor antagonists, the results of the latest clinical trials, and their implications in current clinical practice.     

Thrombolysis and adjunctive therapies in acute myocardial infarction

Thrombolysis and percutaneous transluminal angioplasty represent the cornerstone of the pharmacologic treatment of and the interventional approach to patients with myocardial infarction (MI). They are very effective. However, they are hampered by some critical limitations. Therefore, alternatives to standard thrombolytic therapy have been developed. Platelet glycoprotein (GP) IIb/IIIa blockade is under investigation and seems very attractive. This review will focus on the use of GP IIb/IIIa antagonists and thrombin inhibitors as adjunctive therapies to the thrombolytic treatment of patients with acute MI.