Early abciximab administration before primary percutaneous coronary intervention improves infarct-related artery patency and left ventricular function in high-risk patients with anterior wall myocardial infarction: a randomized study

Prehospital treatment with zalunfiban (RUC-4) in patients with ST- elevation myocardial infarction undergoing primary percutaneous coronary intervention: Rationale and design of the CELEBRATE trial

BACKGROUND

Early and complete restoration of target vessel patency in ST-elevation myocardial infarction (STEMI) is associated with improved outcomes. Oral P2Y₁₂ inhibitors have failed to demonstrate either improved patency or reduced mortality when administered in the prehospital setting. Thus, there is a need for antiplatelet agents that achieve prompt and potent platelet inhibition, and that restore patency in the prehospital setting. Zalunfiban, a novel subcutaneously administered glycoprotein IIb/IIIa inhibitor designed for prehospital administration, has shown to achieve rapid, high-grade platelet inhibition that exceeds that of P2Y₁₂ inhibitors. Whether prehospital administration of zalunfiban can improve clinical outcome is unknown.

HYPOTHESIS

The present study is designed to assess the hypothesis that a single, prehospital injection of zalunfiban given in the ambulance, in addition to standard-of-care in patients with STEMI with intent to undergo primary percutaneous coronary intervention (PCI) will improve clinical outcome compared to standard-of-care with placebo.

STUDY DESIGN

The ongoing CELEBRATE trial (NCT04825743) is a phase 3, randomized, double-blinded, placebo-controlled, international trial. Patients with STEMI intended to undergo primary PCI will receive treatment with a single subcutaneous injection containing either zalunfiban dose 1 (0.110 mg/kg), zalunfiban dose 2 (0.130 mg/kg) or placebo, and the study drug will be administered in the ambulance before transportation to the hospital. A target of 2499 patients will be randomly assigned to one of the treatment groups in a 1:1:1 ratio, ie, to have approximately 833 evaluable patients per group. The primary efficacy outcome is a ranked 7-point scale on clinical outcomes. The primary safety outcome is severe or life-threatening bleeding according to the Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO) criteria.

SUMMARY

The CELEBRATE trial will assess whether a single prehospital subcutaneous injection of zalunfiban in addition to standard-of-care in patients with STEMI with intent to undergo primary PCI will result in improved clinical outcome.

Pre-Hospital Antiplatelet Therapy for STEMI Patients Undergoing Primary Percutaneous Coronary Intervention: What We Know and What Lies Ahead

Early recanalization of the infarct-related artery to achieve myocardial reperfusion is the primary therapeutic goal in patients with ST-elevation myocardial infarction (STEMI). To decrease the duration of ischaemia, continuous efforts have been made to improve pre-hospital treatment and to target the early period after symptom onset. In this period the platelet content of the fresh coronary thrombus is maximal and the thrombi are dynamic, and thus more susceptible to powerful antiplatelet agents. There have been substantial advances in antiplatelet therapy in the last three decades with several classes of oral and intravenous antiplatelet agents with different therapeutic targets, pharmacokinetics, and pharmacodynamic properties. New parenteral drugs achieve immediate inhibition of platelet aggregation, and fast and easy methods of administration may create the opportunity to bridge the initial gap in platelet inhibition observed with oral P2Y12 inhibitors. Moreover, potential future management of STEMI could directly involve patients in the process of care with self-administered antiplatelet agents designed to achieve rapid reperfusion. However, the potential anti-ischaemic benefits of potent antiplatelet agents will need to be balanced against their risk of increased bleeding. This study presents a comprehensive and updated review of pre-hospital antiplatelet therapy among STEMI patients undergoing primary percutaneous intervention and explores new therapies under development.

Application of Auxiliary VerifyNow Point-of-Care Assays to Assess the Pharmacodynamics of RUC-4, a Novel αIIbβ3 Receptor Antagonist

Introduction  Prehospital therapy of ST-elevation myocardial infarction (STEMI) with αIIbβ3 antagonists improves clinical outcomes, but they are difficult to use in prehospital settings. RUC-4 is a novel αIIbβ3 antagonist being developed for prehospital therapy of STEMI that rapidly achieves high-grade platelet inhibition after subcutaneous administration. Standard light transmission aggregometry (LTA) is difficult to perform during STEMI, so we applied VerifyNow (VN) assays to assess the pharmacodynamics of RUC-4 relative to aspirin and ticagrelor.

Methods  Blood from healthy volunteers was anticoagulated with phenylalanyl-prolyl-arginyl chloromethyl ketone (PPACK) or sodium citrate, treated in vitro with RUC-4, aspirin, and/or ticagrelor, and tested with the VN ADP + PGE ₁ , iso-TRAP, and base channel (high concentration iso-TRAP + PAR-4 agonist) assays. The results were correlated with both ADP (20 µM)-induced LTA and flow cytometry measurement of receptor occupancy and data from individuals treated in vivo with RUC-4.

Results  RUC-4 inhibited all three VN assays, aspirin did not affect the assays, and ticagrelor markedly inhibited the ADP + PGE ₁ assay, slightly inhibited the iso-TRAP assay, and did not inhibit the base channel assay. RUC-4's antiplatelet effects were potentiated in citrate compared with PPACK. Cut-off values were determined to correlate the results of the VN iso-TRAP and base channel assays with 80% inhibition of LTA.

Conclusion  The VN assays can differentiate the early potent anti-αIIbβ3 effects of RUC-4 from delayed effects of P2Y12 antagonists in the presence of aspirin. These pharmacodynamic assays can help guide the clinical development of RUC-4 and potentially be used to monitor RUC-4's effects in clinical practice.

First Human Use of RUC-4: A Nonactivating Second-Generation Small-Molecule Platelet Glycoprotein IIb/IIIa (Integrin αIIbβ3) Inhibitor Designed for Subcutaneous Point-of-Care Treatment of ST-Segment-Elevation Myocardial Infarction

Background Despite reductions in door-to-balloon times for primary coronary intervention, mortality from ST-segment-elevation myocardial infarction has plateaued. Early pre-primary coronary intervention treatment of ST-segment-elevation myocardial infarction with glycoprotein IIb/IIIa inhibitors improves pre-primary coronary intervention coronary flow, limits infarct size, and improves survival. We report the first human use of a novel glycoprotein IIb/IIIa inhibitor designed for subcutaneous first point-of-care ST-segment-elevation myocardial infarction treatment. Methods and Results Healthy volunteers and patients with stable coronary artery disease receiving aspirin received escalating doses of RUC-4 or placebo in a sentinel-dose, randomized, blinded fashion. Inhibition of platelet aggregation (IPA) to ADP (20 μmol/L), RUC-4 blood levels, laboratory evaluations, and clinical assessments were made through 24 hours and at 7 days. Doses were increased until reaching the biologically effective dose (the dose producing ≥80% IPA within 15 minutes, with return toward baseline within 4 hours). In healthy volunteers, 15 minutes after subcutaneous injection, mean±SD IPA was 6.9%+7.1% after placebo and 71.8%±15.0% at 0.05 mg/kg (n=6) and 84.7%±16.7% at 0.075 mg/kg (n=6) after RUC-4. IPA diminished over 90 to 120 minutes. In patients with coronary artery disease, 15 minutes after subcutaneous injection of placebo or 0.04 mg/kg (n=2), 0.05 mg/kg (n=6), and 0.075 mg/kg (n=18) of RUC-4, IPA was 14.6%±11.7%, 53.6%±17.0%, 76.9%±10.6%, and 88.9%±12.7%, respectively. RUC-4 blood levels correlated with IPA. Aspirin did not affect IPA or RUC-4 blood levels. Platelet counts were stable and no serious adverse events, bleeding, or injection site reactions were observed. Conclusions RUC-4 provides rapid, high-grade, limited-duration platelet inhibition following subcutaneous administration that appears to be safe and well tolerated. Registration URL: https://www.clini​caltr​ials.gov; Unique identifier: NTC03844191.

Protective approaches against myocardial ischemia reperfusion injury

Myocardial ischemia-reperfusion is the leading cause for the events of cardiovascular disease, and is considered as a major contributor to the morbidity and mortality associated with coronary occlusion. The myocardial damage caused by ischemia-reperfusion injury constitutes the primary pathological manifestation of coronary artery disease. It results from the interaction between the substances that accumulate during ischemia and those that are delivered on reperfusion. The level of this damage can range from a small insult resulting in limited myocardial damage to a large injury culminating in myocyte death. Importantly, major ischemia-reperfusion injury to the heart can result in permanent disability or death. Given the worldwide prevalence of coronary artery disease, developing a strategy to provide cardioprotection against ischemia-reperfusion-induced damage is of great importance. Currently, the treatment of reperfusion injury following ischemia is primarily supportive, since no specific target-oriented therapy has been validated thus far. Nevertheless, therapeutic approaches to protect against myocardial ischemia-reperfusion injury remain an active area of investigation given the detrimental effects of this phenomenon.

Antithrombotic therapy before, during and after emergency angioplasty for ST elevation myocardial infarction

The first three hours after symptom onset hold the maximum potential for myocardial reperfusion and salvage in ST-elevation myocardial infarction (STEMI) patients. During this period timely primary percutaneous coronary intervention (PPCI) or, when PPCI is not promptly feasible, pre-hospital administration of fibrinolyis or a glycoprotein IIb/IIIa-inhibitor (GPI) have been shown to restore coronary patency and reperfusion and even result in myocardial infarction (MI) abortion. On the other hand, oral antiplatelet therapy may not yet guarantee sufficient platelet inhibition. Patients presenting after this golden time have less, if any, benefit from an aggressive antithrombotic treatment prior to PPCI. Antithrombotic treatment during primary angioplasty should be tailored on the basis of the coronary thrombotic burden, vascular approach and the patient's risk of bleeding complications. A GPI-based approach may be favourable in patients presenting early with large MI and high thrombus burden, whereas a bivalirudin-based approach without GPI may be preferred in patients with higher bleeding risk. There are no data to support the use of GPI in bailout conditions. The powerful oral P2Y₁₂ inhibitors, prasugrel and ticagrelor, have been clearly shown to prevent stent thrombosis and recurrent ischaemic events after emergency percutaneous coronary intervention in STEMI patients. Open issues remaining are the treatment of patients with high bleeding risk, such as the elderly and those requiring anticoagulation, as well as the duration of dual antiplatelet therapy after STEMI.

RUC-4: a novel αIIbβ3 antagonist for prehospital therapy of myocardial infarction

OBJECTIVE

Treatment of myocardial infarction within the first 1 to 2 hours with a thrombolytic agent, percutaneous coronary intervention, or an αIIbβ3 antagonist decreases mortality and the later development of heart failure. We previously reported on a novel small molecule αIIbβ3 antagonist, RUC-2, that has a unique mechanism of action. We have now developed a more potent and more soluble congener of RUC-2, RUC-4, designed to be easily administered intramuscularly by autoinjector to facilitate its use in the prehospital setting. Here, we report the properties of RUC-4 and the antiplatelet and antithrombotic effects of RUC-2 and RUC-4 in animal models.

APPROACH AND RESULTS

RUC-4 was ≈ 20% more potent than RUC-2 in inhibiting human ADP-induced platelet aggregation and much more soluble in aqueous solutions (60-80 mg/mL). It shared RUC-2's specificity for αIIbβ3 versus αVβ3, did not prime the receptor to bind fibrinogen, or induce changes in β3 identified by a conformation-specific monoclonal antibody. Both RUC-2 and RUC-4 prevented FeCl3-induced thrombotic occlusion of the carotid artery in mice and decreased microvascular thrombi in response to laser injury produced by human platelets infused into transgenic mice containing a mutated von Willebrand factor that reacts with human but not mouse platelets. Intramuscular injection of RUC-4 in nonhuman primates at 1.9 and 3.85 mg/kg led to complete inhibition of platelet aggregation within 15 minutes, with dose-dependent return of platelet aggregation after 4.5 to 24 hours.

CONCLUSIONS

RUC-4 has favorable biochemical, pharmacokinetic, pharmacodynamic, antithrombotic, and solubility properties as a prehospital therapy of myocardial infarction, but the possibility of increased bleeding with therapeutic doses remains to be evaluated.

Pharmacologic Therapy for Reducing Myocardial Infarct Size in Clinical Trials

In patients with acute ST-segment elevation myocardial infarction, early, successful, and durable reperfusion therapy optimizes the likelihood of favorable outcomes. Fibrinolysis and primary percutaneous coronary intervention improve survival compared to no reperfusion therapy in large part by reducing infarct size (IS) and preserving left ventricular ejection fraction. There is direct correlation between IS and clinical outcomes. In this article, we will review some of the more promising pharmacological agents geared toward reduction in IS, discuss the major pathways that can lead to this desirable outcome, and evaluate the results of clinical trials performed with these and other compounds.

Early administration of abciximab reduces mortality in female patients with ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention (from the EUROTRANSFER Registry)

The present study assessed the impact of early administration of abciximab in female and male patients with ST-segment elevation myocardial infarction (STEMI) transferred for primary angioplasty (PPCI). Data were gathered for 1,650 consecutive patients with STEMI transferred for PPCI from hospital networks in seven countries in Europe from November 2005 to January 2007 (the EUROTRANSFER Registry population). Among 1,086 patients who received abciximab, there were 186 women and 541 men who received abciximab early (>30 min before PPCI), and 86 women and 273 men treated with late abciximab. Female patients were high-risk individuals, with advanced age and increased rate of ischemic events. Early abciximab administration was associated with enhanced patency of the infarct-related artery before PPCI, and improved epicardial flow after PPCI in both women and men. Early abciximab in women led to the decrease in ischemic events, including 30 day (adjusted OR 0.26, 95 % CI 0.10–0.69, p = 0.007) and 1 year (adjusted OR 0.37, 95 % CI 0.16–0.84, p = 0.017) mortality reduction. In contrast, the reduction in 30 day (adjusted OR 0.69, 95 % CI 0.35–1.39, p = 0.27) and 1 year (adjusted OR 0.68, 95 % CI 0.38–1.22, p = 0.19) mortality was not significant in men. The frequency of bleeding events was similar in the early abciximab group compared to the late abciximab group in both women and men. Early administration of abciximab improved patency of the infarct-related artery before and after PPCI, and led to improved survival in female patients with STEMI.

Current state of clinical translation of cardioprotective agents for acute myocardial infarction

There is continued interest in the concept of limiting myocardial infarct size with adjunctive agents administered along with reperfusion injury; however, there remains considerable controversy in the literature. The purpose of this article is to review the medical literature on clinical trials performed during the past 3 years that have attempted to reduce myocardial infarct size by administration of adjunctive therapies along with reperfusion therapy. A PubMed-driven literature search revealed a host of clinical trials focusing on the following prominent types of therapies: endogenous conditioning (postconditioning and remote ischemic conditioning); rapid cooling; pharmacological therapy (cyclosporine, abciximab, clopidogrel, tirofiban, erythropoietin, thrombus aspiration, adenosine, glucose-insulin-potassium, statins, antidiabetic agents, FX06, iron chelation, and ranolazine). Although there remains some controversy, quite a few of these studies showed that adjunctive therapy further reduced myocardial infarct size when coupled with reperfusion. Antiplatelet agents are emerging as some of the newest agents that seem to have cardioprotective capabilities. Postconditioning has become a bit more controversial in the clinical literature; remote conditioning, early and rapid cooling, adenosine, and ranolazine are intriguing therapies deserving of larger studies. Certain agents and maneuvers, such as erythropoietin, protein kinase C δ inhibitors, iron chelation, and intra-aortic balloon counterpulsation, perhaps should be retired. The correct adjunctive therapy administered along with reperfusion has the capability of further reducing myocardial injury during ST-segment-elevation myocardial infarction.

Platelet glycoprotein IIb/IIIa blockers during percutaneous coronary intervention and as the initial medical treatment of non-ST segment elevation acute coronary syndromes

BACKGROUND

During percutaneous coronary intervention (PCI), and in non-ST segment elevation acute coronary syndromes (NSTEACS), the risk of acute vessel occlusion by thrombosis is high. Glycoprotein IIb/IIIa blockers strongly inhibit platelet aggregation and may prevent mortality and myocardial infarction. This is an update of a Cochrane review first published in 2001, and previously updated in 2007 and 2010.

OBJECTIVES

To assess the efficacy and safety effects of glycoprotein IIb/IIIa blockers when administered during PCI, and as initial medical treatment in patients with NSTEACS.

SEARCH METHODS

We updated the searches of the Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (Issue 12, 2012), MEDLINE (OVID, 1946 to January Week 1 2013) and EMBASE (OVID, 1947 to Week 1 2013) on 11 January 2013.

SELECTION CRITERIA

Randomised controlled trials comparing intravenous IIb/IIIa blockers with placebo or usual care.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies for inclusion, assessed trial quality and extracted data. We collected major bleeding as adverse effect information from the trials. We used odds ratios (OR) and 95% confidence intervals (CI) for effect measures.

MAIN RESULTS

Sixty trials involving 66,689 patients were included. During PCI (48 trials with 33,513 participants) glycoprotein IIb/IIIa blockers decreased all-cause mortality at 30 days (OR 0.79, 95% CI 0.64 to 0.97) but not at six months (OR 0.90, 95% CI 0.77 to 1.05). All-cause death or myocardial infarction was decreased both at 30 days (OR 0.66, 95% CI 0.60 to 0.72) and at six months (OR 0.75, 95% CI 0.64 to 0.86), although severe bleeding was increased (OR 1.39, 95% CI 1.21 to 1.61; absolute risk increase (ARI) 8.0 per 1000). The efficacy results were homogeneous for every endpoint according to the clinical condition of the patients, but were less marked for patients pre-treated with clopidogrel, especially in patients without acute coronary syndromes.As initial medical treatment of NSTEACS (12 trials with 33,176 participants), IIb/IIIa blockers did not decrease mortality at 30 days (OR 0.90, 95% CI 0.79 to 1.02) or at six months (OR 1.00, 95% CI 0.87 to 1.15), but slightly decreased death or myocardial infarction at 30 days (OR 0.91, 95% CI 0.85 to 0.98) and at six months (OR 0.88, 95% CI 0.81 to 0.96), although severe bleeding was increased (OR 1.29, 95% CI 1.14 to 1.45; ARI 1.4 per 1000).

AUTHORS' CONCLUSIONS

When administered during PCI, intravenous glycoprotein IIb/IIIa blockers reduce the risk of all-cause death at 30 days but not at six months, and reduce the risk of death or myocardial infarction at 30 days and at six months, at a price of an increase in the risk of severe bleeding. The efficacy effects are homogeneous but are less marked in patients pre-treated with clopidogrel where they seem to be effective only in patients with acute coronary syndromes. When administered as initial medical treatment in patients with NSTEACS, these agents do not reduce mortality although they slightly reduce the risk of death or myocardial infarction.

Platelet glycoprotein IIb/IIIa blockers during percutaneous coronary intervention and as the initial medical treatment of non-ST segment elevation acute coronary syndromes

BACKGROUND

During percutaneous coronary intervention (PCI), and in non-ST segment elevation acute coronary syndromes (NSTEACS), the risk of acute vessel occlusion by thrombosis is high. Glycoprotein IIb/IIIa blockers strongly inhibit platelet aggregation and may prevent mortality and myocardial infarction. This is an update of a Cochrane review first published in 2001, and previously updated in 2007 and 2010.

OBJECTIVES

To assess the efficacy and safety effects of glycoprotein IIb/IIIa blockers when administered during PCI, and as initial medical treatment in patients with NSTEACS.

SEARCH METHODS

We updated the searches of the Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (Issue 12, 2012), MEDLINE (OVID, 1946 to January Week 1 2013) and EMBASE (OVID, 1947 to Week 1 2013) on 11 January 2013.

SELECTION CRITERIA

Randomised controlled trials comparing intravenous IIb/IIIa blockers with placebo or usual care.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies for inclusion, assessed trial quality and extracted data. We collected major bleeding as adverse effect information from the trials. We used odds ratios (OR) and 95% confidence intervals (CI) for effect measures.

MAIN RESULTS

Sixty trials involving 66,689 patients were included. During PCI (48 trials with 33,513 participants) glycoprotein IIb/IIIa blockers decreased all-cause mortality at 30 days (OR 0.79, 95% CI 0.64 to 0.97) but not at six months (OR 0.90, 95% CI 0.77 to 1.05). All-cause death or myocardial infarction was decreased both at 30 days (OR 0.66, 95% CI 0.60 to 0.72) and at six months (OR 0.75, 95% CI 0.64 to 0.86), although severe bleeding was increased (OR 1.39, 95% CI 1.21 to 1.61; absolute risk increase (ARI) 8.0 per 1000). The efficacy results were homogeneous for every endpoint according to the clinical condition of the patients, but were less marked for patients pre-treated with clopidogrel, especially in patients without acute coronary syndromes.As initial medical treatment of NSTEACS (12 trials with 33,176 participants), IIb/IIIa blockers did not decrease mortality at 30 days (OR 0.90, 95% CI 0.79 to 1.02) or at six months (OR 1.00, 95% CI 0.87 to 1.15), but slightly decreased death or myocardial infarction at 30 days (OR 0.91, 95% CI 0.85 to 0.98) and at six months (OR 0.88, 95% CI 0.81 to 0.96), although severe bleeding was increased (OR 1.29, 95% CI 1.14 to 1.45; ARI 1.4 per 1000).

AUTHORS' CONCLUSIONS

When administered during PCI, intravenous glycoprotein IIb/IIIa blockers reduce the risk of all-cause death at 30 days but not at six months, and reduce the risk of death or myocardial infarction at 30 days and at six months, at a price of an increase in the risk of severe bleeding. The efficacy effects are homogeneous but are less marked in patients pre-treated with clopidogrel where they seem to be effective only in patients with acute coronary syndromes. When administered as initial medical treatment in patients with NSTEACS, these agents do not reduce mortality although they slightly reduce the risk of death or myocardial infarction.

From pharmacologically assisted early transfer to a universal primary angioplasty service: the experience of the Małopolska region

The current article summarises more than 12 years' experience in the treatment of ST-segment elevation myocardial infarction in the Małopolska region (southern part of Poland). Data on the development phase of the STEMI treatment network, as well as the current status of interventional treatment of acute coronary syndromes in that region of Poland are provided.

Efficacy of clotinab in acute myocardial infarction trial-ST elevation myocardial infarction (ECLAT-STEMI)

BACKGROUND

This study investigated the efficacy and the safety of the upstream glycoprotein (Gp) IIb/IIIa inhibitor (clotinab; ISU ABXIS, Seoul, Republic of Korea) under 600-mg clopidogrel pretreatment compared with provisional use in ST-elevation myocardial infarction (STEMI).

METHODS AND RESULTS

A total of 786 STEMI patients were randomized to upstream use in the emergency room (ER) (n = 392) or provisional use during percutaneous coronary intervention (PCI) (n = 394). All patients were prescribed 600-mg clopidogrel in the ER. The primary endpoint was the 30-day incidence of composite events including death, nonfatal myocardial infarction, target vessel revascularization, and stroke. There was no significant difference in the events that occurred in 40 patients (10.2%) in the upstream arm and 55 patients (14.0%) in the provisional arm during the 30 days (odds ratio 0.70, 95% confidence interval 0.45-1.08). Major bleeding was higher in the upstream arm (1.5% vs. 0%, P = 0.02). However, there was a significant reduction in 30-day composite events in the upstream arm in the high-risk population (Killip class ≥II or GRACE score >140).

CONCLUSIONS

The upstream use of clotinab under a 600-mg clopidogrel loading may not significantly reduce cardiac events following primary PCI but may improve the clinical outcome in high-risk patients.

Early glycoprotein IIb-IIIa inhibitors in primary angioplasty-abciximab long-term results (EGYPT-ALT) cooperation: individual patient's data meta-analysis

BACKGROUND

Even although time to treatment has been shown to be a determinant of mortality in primary angioplasty, the potential benefits are still unclear from early pharmacological reperfusion by glycoprotein (Gp) IIb-IIIa inhibitors. Therefore, the aim of this meta-analysis was to combine individual data from all randomized trials conducted on upstream as compared with late peri-procedural abciximab administration in primary angioplasty.

METHODS

The literature was scanned using formal searches of electronic databases (MEDLINE and EMBASE) from January 1990 to December 2010. All randomized trials on upstream abciximab administration in primary angioplasty were examined. No language restrictions were enforced.

RESULTS

We included a total of seven randomized trials enrolling 722 patients, who were randomized to early (n = 357, 49.4%) or late (n = 365, 50.6%) peri-procedural abciximab administration. No difference in baseline characteristics was observed between the two groups. Follow-up data were collected at a median (25th-75th percentiles) of 1095 days (720-1967). Early abciximab was associated with a significant reduction in mortality (primary endpoint) [20% vs. 24.6%; hazard ratio (HR) 95% confidence interval (CI) = 0.65 (0.42-0.98) P = 0.02, P(het) = 0.6]. Furthermore, early abciximab administration was associated with a significant improvement in pre-procedural thrombolysis in myocardial infarction (TIMI) 3 flow (21.6% vs. 10.1%, P < 0.0001), post-procedural TIMI 3 flow (90% vs. 84.8%, P = 0.04), an improvement in myocardial perfusion as evaluated by post-procedural myocardial blush grade (MBG) 3 (52.0% vs. 43.2%, P = 0.03) and ST-segment resolution (58.4% vs. 43.5%, P < 0.0001) and significantly less distal embolization (10.1% vs. 16.2%, P = 0.02). No difference was observed in terms of major bleeding complications between early and late abciximab administration (3.3% vs. 2.3%, P = 0.4).

CONCLUSIONS

This meta-analysis shows that early upstream administration of abciximab in patients undergoing primary angioplasty for ST-segment elevation myocardial infarction (STEMI) is associated with significant benefits in terms of pre-procedural epicardial re-canalization and ST-segment resolution, which translates in to significant mortality benefits at long-term follow-up.

Glycoprotein IIb-IIIa inhibitors

Platelets play a pivotal role in the pathogenesis of coronary artery disease and myocardial infarction. Therefore, great interests have been focused in the last decades on improvement in antiplatelet therapies, that currently are regarded as main pillars in the prevention and treatment of coronary artery disease, with special attention to glycoprotein IIb-IIIa (GP IIb-IIIa) receptors, that mediates the final stage of platelet activation. GP IIb-IIIa inhibitors, especially abciximab, have been shown to improve clinical outcome in patients undergoing primary angioplasty for STEMI. Upstream administration cannot routinely recommended, but may potentially be considered among high-risk patients within the first 4 h from symptoms onset. In case of periprocedural administration of antithrombotic therapy, Bivalirudin should be considered, especially in patients at high risk for bleeding complications. Among high-risk patients with acute coronary syndromes, an early invasive strategy with selective downstream administration of GP IIb-IIIa inhibitors is the strategy of choice, whereas bivalirudin should be considered in patients at high risk for bleeding complications. Among patients with unstable angina GP IIb-IIIa inhibitors should be considered only in case of evidence of intracoronary thrombus or in case of thrombotic complications (as provisional use). Further, randomized trials are certainly needed in the era of new oral antiplatelet therapies, and with strategies to prevent bleeding complications such as larger use of radial approach, mechanical closure devices, bivalirudin, or postprocedural protamine administration to promote early sheat removal.

Platelet glycoprotein IIb/IIIa blockers during percutaneous coronary intervention and as the initial medical treatment of non-ST segment elevation acute coronary syndromes

BACKGROUND

During percutaneous coronary intervention (PCI), and in non-ST segment elevation acute coronary syndromes (NSTEACS), the risk of acute vessel occlusion by thrombosis is high. IIb/IIIa blockers strongly inhibit platelet aggregation and may prevent mortality and myocardial infarction (MI). This is an update of a Cochrane review first published in 2001, and previously updated in 2007.

OBJECTIVES

To assess the effects and safety of IIb/IIIa blockers when administered during PCI, and as initial medical treatment in patients with NSTEACS.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (Issue 3, 2009), MEDLINE (1966 to October 2009), and EMBASE (1980 to October 2009).

SELECTION CRITERIA

Randomised controlled trials comparing intravenous IIb/IIIa blockers with placebo or usual care.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies for inclusion, assessed trial quality and extracted data. We collected major bleeding as adverse effect information from the trials. Odds ratios (OR) and 95% confidence intervals (CI) were used for effect measures.

MAIN RESULTS

Forty-eight trials involving 62,417 patients were included. During PCI, IIb/IIIa blockers decreased mortality at 30 days (OR 0.76, 95% CI 0.62 to 0.95) and at six months (OR 0.84, 95% CI 0.71 to 1.00). Death or MI was decreased both at 30 days (OR 0.65, 95% CI 0.60 to 0.72), and at 6 months (OR 0.70, 95% CI 0.61 to 0.81), although severe bleeding was increased (OR 1.38, 95% CI 1.20 to 1.59; absolute risk increase (ARI) 8.0 per 1000). The efficacy results were homogeneous for every endpoint according to the clinical condition of the patients, but were less marked for patients pre-treated with clopidogrel, especially in patients without ACS.As initial medical treatment of NSTEACS, IIb/IIIa blockers did not decrease mortality at 30 days (OR 0.91, 95% CI 0.80 to 1.03) or at six months (OR 1.00, 95% CI 0.87 to 1.15), but slightly decreased death or MI at 30 days (OR 0.92, 95% CI 0.86 to 0.99) and at six months (OR 0.88, 95% CI 0.81 to 0.96), although severe bleeding was increased (OR 1.27, 95% CI 1.12 to 1.43; ARI 1.4 per 1000).

AUTHORS' CONCLUSIONS

When administered during PCI, intravenous IIb/IIIa blockers reduce the risk of death and of death or MI at 30 days and at six months, at a price of an increase in the risk of severe bleeding. The efficacy effects are homogeneous but are less marked in patients pre-treated with clopidogrel where they seem to be effective only in patients with ACS. When administered as initial medical treatment in patients with NSTEACS, these agents do not reduce mortality although they slightly reduce the risk of death or MI.

Transportation with very long transfer delays (>90 min) for facilitated PCI with reduced-dose fibrinolysis in patients with ST-segment elevation myocardial infarction: the Krakow Network

BACKGROUND

The majority of ST-segment elevation myocardial infarction (STEMI) patients are admitted to centers without primary percutaneous coronary intervention (PCI) facilities. Purpose of the study was to determine safety and outcomes in STEMI patients with transfer delay to PCI>90 min receiving half-dose alteplase and abciximab before PCI (facilitated PCI with reduced-dose fibrinolysis).

METHODS AND RESULTS

Outcomes of 669 STEMI patients (<12 h chest pain, non shock, fibrinolysis eligible, <75 years) with transfer delay to PCI>90 min who received half-dose alteplase and full-dose abciximab and were immediately transferred for PCI were compared with primary PCI effects in 1311 patients with transfer delay <90 min. Mean time from symptom-onset to PCI was longer (357 ± 145 min vs. 201 ± 177; P<0.001) in facilitated PCI with reduced-dose fibrinolysis group. In-hospital and 12-month outcomes were similar in both groups, however bleeding events were more frequent in facilitated PCI group (hemorrhagic stroke 0.9% vs. 0%; P<0.001; severe+moderate 5.5% vs. 2.3%; P<0.001).

CONCLUSIONS

This is the first large report showing the safety and benefits of transportation with very long transfer delay (>90 min) for facilitated PCI with reduced-dose fibrinolysis in STEMI patients. In fact, pharmacological treatment (combotherapy) was effective in overcoming the deleterious effects of long time-delay on outcome, with similar survival as compared to short-time transportation, despite higher risk of major bleeding complication.

Early treatment with abciximab in patients with ST elevation myocardial infarction results in a high rate of normal or near normal blood flow in the infarct related artery

There is debate whether early treatment with GpIIb/IIIa inhibitors is of clinical benefit in primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI). This study explored the effects of early given abciximab on coronary blood flow and major adverse cardiac events (MACE) in patients with STEMI treated with primary PCI and adjunctive abciximab. We studied all consecutive patients from our catchment area with STEMI undergoing acute angiography with the intention of primary PCI during 2005. Abciximab was given as early pre-treatment before, (n = 133) or at the cath. lab. after a diagnostic angiography (n = 109). Pre-procedural TIMI 2-3 flow was observed in 45.9 % of patients in the early group versus 20.2 % in the cath. lab. group, P = 0.0001. Mortality rates were 3.8 % versus 3.7% inhospital and 8.3 % versus 7.3% at one year in the early respectively the cath. lab. group, both P = NS. The MACE rate (death, non fatal myocardial infarction, unplanned revascularization) at one year was 19.5 % (early group) and 26.6 % (cath. lab. group), P = 0.19.

CONCLUSION

In this single centre registry study of unselected patients with STEMI early given abciximab was associated with a significantly higher rate of TIMI 2-3 flow compared to abciximab given after the acute angiography.

Early abciximab administration before transfer for primary percutaneous coronary interventions for ST-elevation myocardial infarction reduces 1-year mortality in patients with high-risk profile. Results from EUROTRANSFER registry

BACKGROUND

There are conflicting data on the clinical benefit from early administration of abciximab from a large randomized trial and a registry. However, both sources suggest that a benefit may depend on the baseline risk profile of the patients. We evaluated the role of early abciximab administration in patients with ST-segment-elevation myocardial infarction (STEMI) referred for primary percutaneous coronary intervention stratified by the STEMI Thrombolysis In Myocardial Infarction (TIMI) risk score.

METHODS

A total of 1,650 patients were enrolled into the EUROTRANSFER Registry. One thousand eighty-six patients received abciximab (66%). Abciximab was administered early in 727 patients (EA) and late in 359 patients (LA). We used the TIMI risk score for risk stratification. Patients with scores >or=3 constituted the high-risk group of 616 patients (56.7%), whereas 470 patients formed the low-risk cohort. Factoring in the timing of the abciximab administration resulted in 4 groups of patients who were compared for mortality at 1 year: EA/high-risk (n = 413); LA/high-risk (n = 203); EA/low-risk (n = 314); LA/low-risk (n = 156). Baseline difference was accounted for by means of propensity score.

RESULTS

In high-risk patients, 1-year mortality was significantly lower with early abcximab compared to late administration (8.7% vs 15.8%; odds ratio 0.51, CI 0.31-0.85, P = .01). In multivariable Cox regression analysis, both early abciximab administration and patients' risk profile (TIMI score >or=3) were identified as independent predictors of 1-year mortality.

CONCLUSIONS

Early abciximab administration before transfer for percutaneous coronary intervention in STEMI shows lower mortality at 1-year follow-up. This effect is confined to patients with higher risk profile as defined by TIMI risk score >or=3.

Association between advanced Killip class at presentation and impaired myocardial perfusion among patients with ST-segment elevation myocardial infarction treated with primary angioplasty and adjunctive glycoprotein IIb-IIIa inhibitors

BACKGROUND

Although primary angioplasty has been shown to improve survival as compared with thrombolysis, the outcome is still unsatisfactory in subsets of patients such as those with signs of heart failure at presentation. In fact, although primary angioplasty is able to restore TIMI 3 flow in most patients, suboptimal myocardial reperfusion is observed in a relatively large proportion of patients. The aim of this study was to investigate among patients with ST-segment elevation myocardial infarction undergoing primary angioplasty the association between heart failure at presentation and myocardial perfusion and its implications in terms of survival.

METHODS

Our population is represented by patients undergoing primary angioplasty who are included in the EGYPT database. Congestive heart failure was defined as Killip class >1 at admission. Myocardial perfusion was evaluated by myocardial blush grade and ST-segment resolution. Follow-up data were collected between 30 days and 1 year after primary angioplasty.

RESULTS

Detailed data on Killip class at presentation were available in 1,427 of 1,662 patients (86% of the initial population) who represent the final population of this study. Killip class was associated with myocardial perfusion, distal embolization, enzymatic infarct size, predischarge ejection fraction, and 1-year mortality rate. Myocardial blush was an independent predictor of 1-year mortality (hazard ratio 7.44, 95% CI 1.82-30.4, P = .005) in patients with advanced Killip class at presentation.

CONCLUSIONS

Our study shows that patients with heart failure complicating ST-segment elevation myocardial infarction have impaired myocardial perfusion, which accounts for the poor outcome observed in these patients. Further efforts should be aimed at improving myocardial perfusion, beyond epicardial recanalization, to further improve the outcome of these high-risk patients.

Predicting microvascular obstruction with cardiac troponin T after acute myocardial infarction: a correlative study with contrast-enhanced magnetic resonance imaging

BACKGROUND

The presence of microvascular obstruction (MVO) is associated with more severely impaired left ventricular function and adverse prognosis. The aim of this study was to evaluate whether a single cardiac troponin T-value (cTnT) was able to predict the presence of MVO and whether cTnT is an independent predictor of MVO as compared to usual risk factors.

STUDY DESIGN AND METHODS

Sixty-one consecutive patients with reperfused ST-elevation myocardial infarction (STEMI) were enrolled in the study. cTnT was measured serially at admission and after 24, 48, 72 and 96 h. Contrast-enhanced cardiac magnetic resonance imaging (CE-MRI) was performed on a 1.5T MR-scanner 4 +/- 1 days after STEMI.

RESULTS

cTnT-time concentration kinetics in the presence of MVO differs from cTnT release in the absence of MVO showing a higher peak and a slower release. At single point measurement 24 h-cTnT correlates at least as well with the presence of MVO (P < 0.001) as peak cTnT (P = 0.0016) and sampling over 96 h (P < 0.001). Using ROC analysis, at single measurement a cTnT concentration >2.52 microg/l at 24 h was a predictor for MVO (AUC 0.91) with a sensitivity of 100% and a specificity of 80% with a positive predictive value of 76% and a negative predictive value of 100%. In multivariate regression analysis 24 h-cTnT remained independent predictor for MVO.

CONCLUSIONS

In STEMI, a single 24 h-cTnT value is an independent predictor for MVO and a convenient and inexpensive way to help define this important risk parameter in clinically routine.

Early abciximab administration before primary percutaneous coronary intervention improves clinical outcome in elderly patients transferred with ST-elevation myocardial infarction: data from the EUROTRANSFER registry

BACKGROUND

Limited data are available concerning benefits and risks of early abciximab (EA) administration before primary percutaneous coronary intervention (PPCI) in elderly ST-segment elevation myocardial infarction (STEMI) patients. The objective of the study was to assess the impact of EA before PPCI in elderly (>or=65 years) patients.

METHODS AND RESULTS

We identified 545 patients <65 years (354 with EA administration (>30 min before PPCI), 191 late abciximab (LA)), and 541 patients >or=65 years of age (373 EA, 168 LA) in the EUROTRANSFER Registry database. Elderly patients were more likely to have comorbidities, angiographic PCI complications, and bleeding events. EA promotes infarct-related artery patency before PPCI and improves myocardial reperfusion after PPCI in both age groups, but the risk of 30-day death (EA vs. LA: <65 years, 2.0% vs. 1.6%; p=0.999; >or=65 years, 5.9% vs. 14.3%; p=0.001) and 30-day death+reinfarction (EA vs. LA: <65 years, 2.5% vs. 2.1%; p=0.999; >or=65 years, 7.5% vs. 17.3%; p=0.001) was reduced in elderly patients only. There was no difference in bleedings, especially major bleedings requiring transfusion (EA vs. LA: patients <65 years, 2.3% vs. 0%, p=0.055; >or=65 years, 2.4% vs. 3%; p=0.448) between groups.

CONCLUSIONS

Patients >or=65 years of age have a substantially increased risk of angiographic PCI complications, death and bleeding events compared with their younger counterparts. Strategy of EA before PPCI improves reperfusion parameters and clinical outcome in elderly patients and is not associated with elevated risk of major bleeding.

Early glycoprotein IIb-IIIa inhibitors in primary angioplasty (EGYPT) cooperation: an individual patient data meta-analysis

Background:

Even though time-to-treatment has been shown to be a determinant of mortality in primary angioplasty, the potential benefits from early pharmacological reperfusion by glycoprotein (Gp) IIb–IIIa inhibitors are still unclear. The aim of this meta-analysis was to combine individual data from all randomised trials conducted on facilitated primary angioplasty by the use of early Gp IIb–IIIa inhibitors.

Methods and results:

The literature was scanned by formal searches of electronic databases (MEDLINE, EMBASE) from January 1990 to October 2007. All randomised trials on facilitation by the early administration of Gp IIb–IIIa inhibitors in ST-segment elevation myocardial infarction (STEMI) were examined. No language restrictions were enforced. Individual patient data were obtained from 11 out of 13 trials, including 1662 patients (840 patients (50.5%) randomly assigned to early and 822 patients (49.5%) to late Gp IIb–IIIa inhibitor administration). Preprocedural Thrombolysis in Myocardial Infarction Study (TIMI) grade 3 flow was more frequent with early Gp IIb–IIIa inhibitors. Postprocedural TIMI 3 flow and myocardial blush grade 3 were higher with early Gp IIb–IIIa inhibitors but did not reach statistical significance except for abciximab, whereas the rate of complete ST-segment resolution was significantly higher with early Gp IIb–IIIa inhibitors. Mortality was not significantly different between groups, although early abciximab demonstrated improved survival compared with late administration, even after adjustment for clinical and angiographic confounding factors.

Conclusions:

This meta-analysis shows that pharmacological facilitation with the early administration of Gp IIb–IIIa inhibitors in patients undergoing primary angioplasty for STEMI is associated with significant benefits in terms of preprocedural epicardial recanalisation and ST-segment resolution, which translated into non-significant mortality benefits except for abciximab.