Prehospital initiation of tirofiban in patients with ST-elevation myocardial infarction undergoing primary angioplasty (On-TIME 2): a multicentre, double-blind, randomised controlled trial

[Antiplatelet therapy and anticoagulation in acute coronary syndrome: current evidence]

In recent years, the prognosis of patients with an acute coronary syndrome (ACS) has significantly improved. This can mainly be attributed to the implementation of primary percutaneous coronary intervention (PCI). Apart from mechanical reperfusion, an optimal medical strategy is of great importance. Antiplatelet and antithrombotic therapies in particular play a crucial role in the management of patients with ACS. New options in antiplatelet therapy are more potent P2Y12 inhibitors in addition to acetylsalicylic acid and clopidogrel. Furthermore, anticoagulant therapy before, during and after PCI can be performed by the use of unfractionated heparin, low molecular weight heparins, such as enoxaparin, the synthetic pentasaccharide fondaparinux and the direct thrombin inhibitor bivalirudin with or without additional administration of glycoprotein IIb/IIIa inhibitors. In this article, data on antiplatelet and anticoagulant therapy are presented and the current evidence is discussed.

Efficacy of pre-hospital use of glycoprotein IIb/IIIa inhibitors in ST-segment elevation myocardial infarction before mechanical reperfusion in a rapid-transfer network (from the Acute Myocardial Infarction Registry of Brittany)

Previous studies investigating prehospital use of glycoprotein IIb/IIIa inhibitors (GPIs) in patients with ST-segment elevation myocardial infarction reached conflicting conclusions. The benefit of this strategy in addition to in-ambulance loading of dual-antiplatelet therapy remains controversial. The aim of this study was to analyze data from a prospective registry of patients with ST-segment elevation myocardial infarctions admitted <24 hours after symptom onset (July 2006 to May 2012). A total of 2,052 patients managed in a physician-staffed mobile intensive care unit (MICU)<12 hours after symptom onset and scheduled for primary percutaneous coronary intervention (PPCI) were retrospectively included. Patients who received GPIs in the MICU were compared with those who did not. The primary end point was infarct-related artery patency, defined as pre-PPCI Thrombolysis In Myocardial Infarction (TIMI) flow grade 3. GPIs were administered in the MICU to 737 patients (36%), including 430<2 hours after symptom onset, and 1,315 patients (64%) did not received prehospital GPIs. Pre-PPCI TIMI flow grade 3 rate was lower in patients treated in the MICU (17.2% vs 21.3%, p=0.03) because of patients treated >2 hours after symptom onset, of whom only 12.7% reached the primary end point. There was no significant difference between groups in the rate of in-hospital major adverse cardiac events. In conclusion, prehospital GPI use in patients with ST-segment elevation myocardial infarctions<12 hours after symptom onset scheduled for PPCI neither improved pre-PPCI infarct-related artery patency nor reduced in-hospital major adverse cardiac events.

CYP2C19 genotype-guided antiplatelet therapy in ST-segment elevation myocardial infarction patients-Rationale and design of the Patient Outcome after primary PCI (POPular) Genetics study

RATIONALE

In patients with ST-segment elevation myocardial infarction (STEMI) who undergo primary percutaneous coronary intervention (pPCI), the use of dual antiplatelet therapy is essential to prevent atherothrombotic complications. Therefore, patients are treated with acetylsalicylic acid and clopidogrel, prasugrel, or ticagrelor. Clopidogrel, however, shows a major interindividual variation in antiplatelet effect, which is correlated to an increase in atherothrombotic events in patients with high platelet reactivity. This interindividual variation is partly a result of CYP2C19 genetic variants. Ticagrelor and prasugrel reduce atherothrombotic events but increase bleeding rate and drug costs, as compared with clopidogrel. CYP2C19-based tailoring of antiplatelet therapy might be beneficial to STEMI patients.

STUDY DESIGN

POPular Genetics (NCT01761786) is a randomized, open-label, multicenter trial involving 2,700 STEMI patients who undergo pPCI. Patients are randomized to CYP2C19 genotyping or routine ticagrelor or prasugrel treatment. In the genotyping group, *1/*1 (wild-type) patients receive clopidogrel, and patients carrying 1 or 2 *2 or *3 loss-of-function alleles receive ticagrelor or prasugrel. The primary net clinical benefit end point is the composite of death, (recurrent) myocardial infarction, definite stent thrombosis, stroke, and Platelet Inhibition and Patient Outcomes (PLATO) major bleeding at 1 year. Primary safety end point is the composite of (PLATO) major and minor bleeding. Cost-effectiveness and quality of life will be assessed by calculating quality-adjusted life-years, net costs per life-year, and per quality-adjusted life-year gained.

CONCLUSION

The POPular Genetics study is the first large-scale trial comparing CYP2C19 genotype-guided antiplatelet therapy to a nontailored strategy in terms of net clinical benefit, safety, and cost-effectiveness.

Coronary thrombus in patients undergoing primary PCI for STEMI: Prognostic significance and management

Acute ST-elevation myocardial infarction (STEMI) usually results from coronary atherosclerotic plaque disruption with superimposed thrombus formation. Detection of coronary thrombi is a poor prognostic indicator, which is mostly proportional to their size and composition. Particularly, intracoronary thrombi impair both epicardial blood flow and myocardial perfusion, by occluding major coronary arteries and causing distal embolization, respectively. Thus, although primary percutaneous coronary intervention is the preferred treatement strategy in STEMI setting, the associated use of adjunctive antithrombotic drugs and/or percutaneous thrombectomy is crucial to optimize therapy of STEMI patients, by improving either angiographical and clinical outcomes. This review article will focus on the prognostic significance of intracoronary thrombi and on current antithrombotic pharmacological and interventional strategies used in the setting of STEMI to manage thrombotic lesions.

Management and outcomes of patients presenting with STEMI by use of chronic oral anticoagulation: results from the GRACE registry

AIMS

To describe the characteristics, treatment, and mortality in patients with ST-elevation myocardial infarction (STEMI) by use of chronic oral anticoagulant (OAC) therapy.

METHODS

Using data from the Global Registry of Acute Coronary Syndromes (GRACE), patient characteristics, treatment, and reperfusion strategies of STEMI patients on chronic OAC are described, and relevant variables compared with patients not on chronic OAC. Six-month post-discharge mortality rates were evaluated by Cox proportional hazard models.

RESULTS

Of 19,094 patients with STEMI, 574 (3.0%) were on chronic OAC at admission. Compared with OAC non-users, OAC users were older (mean age 73 vs. 65 years), more likely to be female (37 vs. 29%), were more likely to have a history of atrial fibrillation, prosthetic heart valve, venous thromboembolism, or stroke/transient ischaemic attack, had a higher mean GRACE risk score (166 vs. 145), were less likely to be Killip class I (68 vs. 82%), and were less likely to undergo catheterization/percutaneous coronary intervention (52 vs. 66%, respectively). Of the patients who underwent catheterization, fewer OAC users had the procedure done within 24 h of admission (56.5 vs. 64.5% of OAC non-users). In propensity-matched analyses (n=606), rates of in-hospital major bleeding and in-hospital and 6-month post-discharge mortality were similar for OAC users and OAC non-users (2.7 and 3.7%, p=0.64; 15 and 13%, p=0.56; 15 and 12%, p=0.47, respectively), rates of in-hospital recurrent myocardial infarction (8.6 and 2.0%, p<0.001) and atrial fibrillation (32 and 22%, p=0.004) were higher in OAC patients, and rates of 6-month stroke were lower (0.6 and 4.3%, p=0.038). Patients in both groups who underwent catheterization had lower mortality than those who did not undergo catheterization.

CONCLUSIONS

This is the largest study to describe the characteristics and treatment of STEMI patients on chronic OAC. The findings suggest that patients on chronic OAC are less likely to receive guideline-indicated management, but have similar adjusted rates of in-hospital and 6-month mortality.

Bivalirudin is superior to heparins alone with bailout GP IIb/IIIa inhibitors in patients with ST-segment elevation myocardial infarction transported emergently for primary percutaneous coronary intervention: a pre-specified analysis from the EUROMAX trial

Aims

In the HORIZONS trial, in-hospital treatment with bivalirudin reduced bleeding and mortality in primary percutaneous coronary intervention (PCI) compared with heparin and routine glycoprotein IIb/IIIa inhibitors (GPI). It is unknown whether this advantage of bivalirudin is observed in comparison with heparins only with GPI used as bailout.

Methods and results

In the EUROMAX study, 2198 patients with ST-segment elevation myocardial infarction (STEMI) were randomized during transport for primary PCI to bivalirudin or to heparins with optional GPI. Primary and principal outcome was the composites of death or non-CABG-related major bleeding at 30 days. This pre-specified analysis compared patients receiving bivalirudin (n = 1089) with those receiving heparins with routine upstream GPI (n = 649) and those receiving heparins only with GPI use restricted to bailout (n = 460). The primary outcome death and major bleeding occurred in 5.1% with bivalirudin, 7.6% with heparin plus routine GPI (HR 0.67 and 95% CI 0.46–0.97, P = 0.034), and 9.8% with heparins plus bailout GPI (HR 0.52 and 95% CI 0.35–0.75, P = 0.006). Following adjustment by logistic regression, bivalirudin was still associated with significantly lower rates of the primary outcome (odds ratio 0.53, 95% CI 0.33–0.87) and major bleeding (odds ratio 0.44, 95% CI 0.24–0.82) compared with heparins alone with bailout GPI. Rates of stent thrombosis were higher with bivalirudin (1.6 vs. 0.6 vs. 0.4%, P = 0.09 and 0.09).

Conclusion

Bivalirudin, started during transport for primary PCI, reduces major bleeding compared with both patients treated with heparin only plus bailout GPI and patients treated with heparin and routine GPI, but increased stent thrombosis.

The Safety and Efficacy of 12 Versus 24 Hours of Tirofiban Infusion in Patients Undergoing Primary Percutaneous Coronary Intervention

Aim:

We aimed to investigate the 6-month efficacy and safety of postprocedural 12-hour tirofiban administration versus 24-hour tirofiban administration in patients with ST-segment elevated myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention (PCI).

Methods:

This retrospective study enrolled 349 patients with STEMI who underwent primary PCI. Following the administration of bolus tirofiban after primary PCI, those receiving a 12-hour tirofiban infusion as the maintenance dose were classified as group 1 (n = 123) while those receiving a 24-hour infusion were classified as group 2 (n = 226). In-hospital and 6-month major adverse cardiac events were recorded.

Results:

There were no statistically significant differences between the 2 groups regarding in-hospital efficacy (in-hospital death: 4.4% vs 5.7%, P = .600 and stent thrombosis 1.8% vs 1.6%, P = .921) and in-hospital safety (2.6% vs 1.6% for major bleeding and 5.3% vs 4.1% for minor bleeding, P = .562). During the 6-month follow-up period, the incidence of the recurrent revascularization (16.1% vs 15.5%, odds ratio [OR] = 1.05 [0.47-3.67]), the repeated nonfatal acute coronary syndrome and/or stent thrombosis (27% vs 24.4%, P = .598, OR = 1.02 [0.42-2.48]), and the cardiovascular deaths (6.6% vs 6.5%, P = .943, OR = 1.03 [0.43-2.43]) were comparable between group 1 and group 2.

Conclusion:

Our study revealed that 12-hour tirofiban administration versus 24-hour tirofiban administration in STEMI who underwent primary PCI was similar with respect to in-hospital efficacy and safety and major adverse cardiac events during 6-month follow-up.

Effect of Early Treatment With Tirofiban on Initial TIMI Grade 3 Flow of Patients With ST Elevation Myocardial Infarction

Background:

Before primary percutaneous coronary intervention (PCI) in patients with ST elevation myocardial infarction (STEMI), it is not clear whether a routine early administration of glycoprotein IIb/IIIa inhibitors in the emergency ward is beneficial or their administration in selected cases in the catheterization laboratory.

Objectives:

The present randomized clinical trial sought to investigate whether an earlier administration of Tirofiban could exert any impact on TIMI grade 3 flows and ST resolution in the electrocardiography of patients with STEMI before primary PCI.

Materials and Methods:

Patients with STEMI within twelve hours of symptom commencement were included if primary PCI was planned to be performed within ninety minutes of admission and excluded if they had contraindications for Tirofiban. Seventy patients were randomized to receive 25 μg/kg of bolus Tirofiban early in the emergency ward (the early Tirofiban group) in three minutes and 70 did not receive Tirofiban (the control group). The primary endpoint of the study was a Thrombolysis in Myocardial Infarction (TIMI) grade 3 flows on the initial angiogram. The study is registered as IRCT201105126463N1 in: www.irct.ir.

Results:

The study population had a mean age of 57.17 ± 10.09 years and included 79.3 % males. TIMI grade 3 flow was seen in 15 (21.4 %) patients of the Tirofiban group and 7 (10 %) of the control group (P = 0.06, odds ratio = 0.407, and 95 % confidence interval = 0.155-1.072). Complete ST resolution was seen in 30 (42.9 %) patients of the Tirofiban group and 34 (48.6 %) of the control group (P = 0.5).

Conclusion:

Although TIMI grade 3 flows trended to be higher in the patients who received early Tirofiban in the emergency ward, the difference did not constitute statistical significance and possible benefits, therefore, require further clarification.

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.

Contemporary antiplatelet therapy in patients undergoing percutaneous coronary intervention

The proper use of antiplatelet agents in the cardiac catheterization laboratory is important for ensuring optimal results in patients undergoing percutaneous revascularization. Understanding the mechanisms by which these drugs exerts their effects is important for both interventional and non-interventional cardiologists. The effects of these agents on platelet function can be assessed and monitored using a variety of commercially available laboratory assays but so far these tests have not been adopted in routine clinical practice. Currently, aspirin, thienopyridines and glycoprotein IIb/IIIa inhibitors are the primary types of antiplatelet drugs being utilized. The use of these drugs and of several newer antiplatelet drugs in the treatment of patients undergoing percutaneous revascularization in the cardiac catheterization laboratory will be discussed, especially in the light of the recently published guidelines.

Risks and Benefits of Thrombolytic, Antiplatelet, and Anticoagulant Therapies for ST Segment Elevation Myocardial Infarction: Systematic Review

Objectives. Assess the impact of associating thrombolytics, anticoagulants, antiplatelets, and primary angioplasty (PA) on death, reinfarction (AMI), and major bleeding (MB) in STEMI therapy. Methods. Medline search was performed to identify randomized trials comparing these classes in STEMI treatment, at least 500 patients, providing death, AMI, and MB rates. Similar arms were grouped. Correlation between number of drugs and PA and the outcomes was evaluated, as well as correlation between the year of the study and the outcomes. Results. Fifty-nine papers remained after exclusions. 404.556 patients were divided into 35 groups of arms. There was correlation between the number of drugs and rates of death (r = -0.466, P = 0.005) and MB (r = 0.403, P = 0.016), confirmed by multivariate regression. This model also showed that PA is associated with lower mortality and increased MB. Year and period of publication correlated with the outcomes: death (r = -0.380, P < 0.001), MB (r = 0.212, P = 0.014), and AMI (r = -0.231, P = 0.009). Conclusion. The increasing complexity of STEMI treatment has resulted in significant reduction in mortality along with increased rates of MB. Overall, however, the benefits of treatment outweigh the associated risks of MB.

Spontaneous and procedural plaque embolisation in native coronary arteries: pathophysiology, diagnosis, and prevention

The detachment of atherothrombotic material from the atherosclerotic coronary plaque and downstream embolisation is an underrecognized phenomenon and it causes different degrees of impairment of the coronary microcirculation. During treatment of obstructive atherosclerotic plaque by percutaneous coronary intervention (PCI) distal embolisation (DE) is considered to be inevitable and it is associated with potential clinical and prognostic implications. This review aims to assess the main aspects of both spontaneous and procedural DE, analyze their different pathophysiology, provide specific insights on the main diagnostic tools for their identification, and finally focus on the main strategies for their treatment and prevention.

Effects of Upstream Administration of Tirofiban Before Percutaneous Coronary Intervention on Spontaneous Reperfusion and Clinical Outcomes in Acute ST-Segment Elevation Myocardial Infarction

We assessed the effects of upstream administration of the glycoprotein IIb/IIIa inhibitor tirofiban before percutaneous coronary intervention (PCI) on spontaneous reperfusion (SR) of infarct-related artery (IRA) and the clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI). The incidence of SR of the IRA was significantly higher in the tirofiban group than in the no-tirofiban group (141 [36.5%] vs 21 [17.2%], P < .001). By multivariate logistic regression analysis, use of tirofiban (odds ratio 2.32, 95% confidence interval 1.25-4.31, P = .008) independently predicted the occurrence of SR. Kaplan-Meier survival analysis demonstrated that major adverse cardiovascular event-free survival was significantly higher in patients treated with tirofiban than in patients without tirofiban at 30-day (log rank = 11.65, P = .001) and 90-day follow-up (log rank = 16.79, P < .001). Upstream administration of tirofiban is significantly associated with increased SR of the IRA and favorable clinical prognosis in patients undergoing PCI for STEMI.

Design and methods of European Ambulance Acute Coronary Syndrome Angiography Trial (EUROMAX): an international randomized open-label ambulance trial of bivalirudin versus standard-of-care anticoagulation in patients with acute ST-segment-elevation myocardial infarction transferred for primary percutaneous coronary intervention

BACKGROUND

In patients with ST-segment elevation myocardial infarction (STEMI) triaged to primary percutaneous coronary intervention (PCI), anticoagulation often is initiated in the ambulance during transfer to a PCI site. In this prehospital setting, bivalirudin has not been compared with standard-of-care anticoagulation. In addition, it has not been tested in conjunction with the newer P2Y12 inhibitors prasugrel or ticagrelor.

DESIGN

EUROMAX is a randomized, international, prospective, open-label ambulance trial comparing bivalirudin with standard-of-care anticoagulation with or without glycoprotein IIb/IIIa inhibitors in 2200 patients with STEMI and intended for primary percutaneous coronary intervention (PCI), presenting either via ambulance or to centers where PCI is not performed. Patients will receive either bivalirudin given as a 0.75 mg/kg bolus followed immediately by a 1.75-mg/kg per hour infusion for ≥30 minutes prior to primary PCI and continued for ≥4 hours after the end of the procedure at the reduced dose of 0.25 mg/kg per hour, or heparins at guideline-recommended doses, with or without routine or bailout glycoprotein IIb/IIIa inhibitor treatment according to local practice. The primary end point is the composite incidence of death or non-coronary-artery-bypass-graft related protocol major bleeding at 30 days by intention to treat.

CONCLUSION

The EUROMAX trial will test whether bivalirudin started in the ambulance and continued for 4 hours after primary PCI improves clinical outcomes compared with guideline-recommended standard-of-care heparin-based regimens, and will also provide information on the combination of bivalirudin with prasugrel or ticagrelor.

Efficacy and safety of tirofiban-supported primary percutaneous coronary intervention in patients pretreated with 600 mg clopidogrel: results of propensity analysis using the Clinical Center of Serbia STEMI Register

BACKGROUND

Studies with platelet glycoprotein IIb/IIIa receptor inhibitors (GPIs) showed conflicting results in primary percutaneous coronary intervention (PPCI) patients who were pretreated with 600 mg clopidogrel. We sought to investigate the short- and long-term efficacy and safety of the periprocedural administration of tirofiban in a largest Serbian PPCI centre.

METHODS

We analysed 2995 consecutive PPCI patients enrolled in the Clinical Center of Serbia STEMI Register, between February 2007 and March 2012. All patients were pretreated with 600 mg clopidogrel and 300 mg aspirin. Major adverse cardiovascular events, comprising all-cause death, nonfatal infarction, nonfatal stroke, and ischaemia-driven target vessel revascularization, was the primary efficacy end point. TIMI major bleeding was the key safety end point.

RESULTS

Analyses drawn from the propensity-matched sample showed improved primary efficacy end point in the tirofiban group at 30-day (OR 0.72, 95% CI 0.53-0.97) and at 1-year (OR 0.74, 95% CI 0.57-0.96) follow up. Moreover, tirofiban group had a significantly lower 30-day all-cause mortality (secondary end point; OR 0.63, 95% CI 0.40-0.90), compared with patients who were not administered tirofiban. At 1 year, a trend towards a lower all-cause mortality was observed in the tirofiban group (OR 0.74, 95% CI 0.53-1.04). No differences were found with respect to the TIMI major bleeding during the follow-up period.

CONCLUSIONS

Tirofiban administered with PPCI, following 600 mg clopidogrel pretreatment, improved primary efficacy outcome at 30 days and at 1 year follow up without an increase in major bleeding.

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.

Synergistic effect of thrombus aspiration and abciximab in primary percutaneous coronary intervention

BACKGROUND

Previous studies failed to assess the individual prognostic role of thrombus aspiration (TA) or abciximab in primary percutaneous coronary intervention (pPCI), due their prevalent combined use.

METHODS AND RESULTS

A total of 644 consecutive ST-segment elevation myocardial infarction patients treated with pPCI were included in this retrospective registry from January 2006 to December 2008. Patients were divided in: (a) Group 1, with conventional pPCI; (b) Group 2, with pPCI and abciximab; (c) Group 3, with pPCI and TA; (d) Group 4, with pPCI and abciximab plus TA. Primary end point was the composite of major adverse cardiovascular events (MACEs, defined as overall mortality, myocardial infarction, target vessel revascularization, and major bleedings) at 1 year. Baseline clinical and angiographic characteristics were not different among the groups, with the exception of a younger age in group 4. The two groups of patients treated with TA (group 3 and 4) received more frequently direct stenting (P < 0.001 vs. group 1 for both), presented higher rate of end-procedural TIMI flow grade 3 (P < 0.001 vs. group 1 for both), and lower rate of no-reflow (P = 0.016 and P < 0.001 vs. group 1, respectively). Patients of group 2 presented a borderline nonsignificant trend toward higher rate of end-procedural TIMI flow grade 3 (P = 0.083 vs. group 1). MACEs at 1 year were 43 (29%) in group 1 versus 25 (22%) in group 2 versus 24 (19%) in group 3 versus 32 (13%) in group 4 (log-rank P = 0.001). At the multivariate Cox regression analysis, combined TA plus abciximab in group 4 [hazard ratio (HR): 0.48, confidence interval (CI) 95% 0.28-0.84, P = 0.01] and a higher left ventricular ejection fraction (HR: 0.97, CI 95% 0.95-0.98, P < 0.001) were significantly associated with lower MACE rate.

CONCLUSIONS

The combination of pharmacologic and mechanic antithrombotic treatment during pPCI was associated with better 1-year clinical outcome.

Combination Antithrombotic Management of STEMI with Pharmacoinvasive Strategy, Primary PCI, or Rescue PCI

The mainstay of acute ST segment elevation myocardial infarction (STEMI) emergent management consists of reperfusion therapy combined with antithrombotic treatment. Primary percutaneous coronary intervention (PCI) is the preferred reperfusion strategy for STEMI. Rescue PCI consists of urgent transfer for PCI of patients with failed fibrinolysis. The pharmacoinvasive strategy consists of administration of fibrinolysis followed by immediate transfer to a PCI-capable hospital for routine early catheterization. This article provides an overview of data and recommendations on primary PCI, rescue PCI, and pharmacoinvasive strategy as well as of the antithrombotic regimens used to support STEMI reperfusion approaches.

Strategies TO reduce time delays in patients with AcuTe coronary heart disease treated with primary PCI--the STOP WATCH study: a multistage action research project

OBJECTIVE

To identify, evaluate and reduce system delay times in an ST-elevation myocardial infarction (STEMI) network by targeted reorganisation of logistics and personal feedback to staff on time delays.

DESIGN

Multistage action research project. Three study phases were used (exploration, tailored intervention and evaluation).

SETTING

Single centre study, Sweden.

PATIENTS

Consecutive patients (N=156) with prehospital STEMI onset treated with primary percutaneous coronary intervention (PCI).

INTERVENTIONS

Areas of delays were identified through participant observations and collaborative discussions. To increase the awareness of delay factors, continuous feedback on time delays was given. Elements of the logistics' reorganisation were (1) prioritised ECG recording by emergency medical services personnel, (2) central evaluation of ECG in all patients and (3) start of PCI procedure when two of three PCI team members were on site. Multiple key time measurements were made before (N=67) and after (N=89) the intervention.

MAIN OUTCOMES

Time difference (minutes) in system delay between the preintervention and postintervention phases.

RESULTS

Time from first medical contact (FMC) to a patent artery and time from FMC-to-catheter laboratory (cath-lab) arrival decreased by 6 and 12 min, respectively (ns). Time from FMC-to-ECG recording remained unchanged after the intervention. Time from ECG to decision for primary PCI was reduced by 6 min, p=0.004 and time from ECG-to-cath-lab arrival by 11 min, p=0.02. Total time from diagnosis to a patent artery decreased by 11 min (ns).

CONCLUSIONS

Identification of time delays in an STEMI network with awareness of delay factors, reorganisation of logistics and continuous feedback can reduce system delay times significantly.

Effects of tirofiban maintenance duration on myocardial perfusion defect severity in anterior myocardial infarction

INTRODUCTION

Percutaneous coronary intervention (PCI) does not often produce optimal results, despite restoration of coronary blood flow at myocardial recovery, because of impaired microvascular perfusion. This study aimed to investigate and evaluate with (99m)Tc-sestamibi scan whether the results of PCI can be changed by maintenance infusion of tirofiban for 24 or 48 h in patients presenting with anterior ST-elevation myocardial infarction (STEMI).

METHODS

The study included 84 patients with anterior STEMI who were candidates for primary PCI and whose occlusion was in the proximal or mid-left anterior descending artery. Patients were given 25 μg/kg/3 min tirofiban and randomized to receive maintenance infusion at 0.15 μg/kg/min for 24 or 48 h. A resting (99m)Tc sestamibi scan was performed on the 5th day post-procedure before discharge. The primary efficacy endpoint was a patient's score on a 5-point scoring system for perfusion defect severity. Major adverse cardiac events (MACE) were defined as death from any cause, re-infarction, and clinically driven target-vessel revascularization within the first 6 months.

RESULTS

Baseline characteristics of the patients were similar in the two infusion groups (n = 42 per group). There was no significant difference in the symptom onset-to-presentation time or door-to-balloon time between the two groups. With the exception of basal anteroseptal and basal anterior segments, significant reductions were obtained on the 5-point scoring system for perfusion defect severity in segments and in the summed rest scores. No significant differences were observed between the two groups in the incidence of MACE at 6 months. The safety profile did not differ between 24 and 48 h infusions of tirofiban.

CONCLUSION

The use of tirofiban, when administered at a high bolus dose and maintained for 48 h, was safe and significantly reduced perfusion defect severity in patients with anterior STEMI presenting early after symptom onset and undergoing primary PCI.

What is the optimum adjunctive reperfusion strategy for primary percutaneous coronary intervention?

Acute ST-segment elevation myocardial infarction (STEMI) is a dynamic, thrombus-driven event. As understanding of its pathophysiology has improved, the central role of platelets in initiation and orchestration of this process has become clear. Key components of STEMI include formation of occlusive thrombus, mediation and ultimately amplification of the local vascular inflammatory response resulting in increased vasoreactivity, oedema formation, and microvascular obstruction. Activation, degranulation, and aggregation of platelets are the platforms from which these components develop. Therefore, prompt, potent, and predictable antithrombotic therapy is needed to optimise clinical outcomes after primary percutaneous coronary intervention. We review present pharmacological and mechanical adjunctive therapies for reperfusion and ask what is the optimum combination when primary percutaneous coronary intervention is used as the mode of revascularisation in patients with STEMI.

Short-term effect of upstream administration in comparison to deferred injection of tirofiban on patients with acute ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

BACKGROUND

High bolus dose tirofiban has been demonstrated to provide greater inhibition of platelet aggregation, but the most appropriate timing of its administration remains unknown.

OBJECTIVES

To evaluate the efficacy of upstream vs. deferred administration of tirofiban in patients with acute ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention (PCI) on clinical outcomes.

METHODS

The 660 patients with acute ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention were divided into upstream (n=330, administration of tirofiban to all patients in emergency room) and deferred groups (n=330, treatment of patients with large thrombus burden or no-reflow phenomenon in cardiac catheterization laboratory during PCI). The primary end-points were death, nonfatal myocardial infarction (MI), stent thrombosis (ST), revascularization of targeted vessels (TVR) or major adverse cardiac events (MACE) at 1 month and 6 months following PCI, with safety end-point at 7 days.

RESULTS

Compared with that of the deferred group, there was a significant increase of left ventricular ejection fraction (LVEF) in the upstream group within 7 days (55.5 ± 6.6% vs. 54.6 ± 7.9%, P=0.011). The rates of 7-day and 1-month MACE in the upstream group were lower than those in the deferred group (1.5% vs. 4.2%, 3.3% vs. 7.0%, P=0.037 and 0.034, respectively). However, there were higher tendencies for major and minor bleedings in the upstream group (1.8% vs. 0.9%, 2.7% vs. 1.5%, P=0.315 and 0.280, respectively).

CONCLUSION

To the Chinese patients with acute myocardial infarction undergoing primary PCI, upstream administration of tirofiban was slightly superior to deferred injection for short-term clinical outcomes.

Treating and preventing no reflow in the cardiac catheterization laboratory

The no reflow phenomenon can happen during elective or primary percutaneous coronary intervention. This phenomenon is thought to be a complex process involving multiple factors that eventually lead to microvascular obstruction and endothelial disruption. Key pathogenic components include distal atherothrombotic embolization, ischemic injury, reperfusion injury, and susceptibility of coronary microcirculation to injury. Thus, pharmacologic and mechanical strategies to prevent and treat no reflow target these mechanisms. Specifically, pharmacologic therapy consisting of vasodilators and antiplatelet agents have shown benefit in the treatment of no-reflow and mechanical therapies such as distal protection and aspiration thrombectomy have also shown benefit.

Management of the acute cardiac patient in the Australian rural setting: a 12 month retrospective study

BACKGROUND

Rural cardiac patients may require transfer to tertiary health services for ongoing acute cardiac management. The time required to transfer is a consideration in determining appropriate clinical care. There is little published data reporting acute cardiac management in the Australian regional setting that reviews factors determining transfer to a tertiary centre.

PURPOSE

This paper reports the findings of a quantitative, retrospective study conducted to identify demographic differences and potential predictors to urban transfer for ongoing acute cardiac management for patients presenting to a regional hospital with suspected acute myocardial infarction.

METHODS

Using a purpose designed tool an audit of 204 files from June 2009 to July 2010 was conducted for all patients admitted to a regional hospital having a discharge diagnosis of acute myocardial infarction or angina. Patient demographics, clinical outcomes, concordance with treatment guidelines, and possible predictors of treatment decisions were investigated.

FINDINGS

Patients younger than 65 years (p<0.001), unemployed (p<0.01) and with acute electrocardiograph changes (p<0.01) were more likely to be transferred to a tertiary centre. Treatment guidelines concordance for acute cardiac care ranged from 70% to 79% for all patients.

CONCLUSIONS

Although presenting patients were treated in a timely manner consistent with national guidelines, to be younger, unemployed or have electrocardiograph changes was a greater predictor to urban transfer. It is unknown if these differences in transferring or not to a tertiary centre contribute to poorer long-term cardiac outcomes for rural patients. Further evaluations are warranted.

Ambulance or in-catheterization laboratory administration of ticagrelor for primary percutaneous coronary intervention for ST-segment elevation myocardial infarction: rationale and design of the randomized, double-blind Administration of Ticagrelor in the cath Lab or in the Ambulance for New ST elevation myocardial Infarction to open the Coronary artery (ATLANTIC) study

Primary percutaneous coronary intervention (PCI) is the treatment of choice for patients presenting with acute ST-segment elevation myocardial infarction (STEMI). However, if catheterization facilities are not immediately available, the effectiveness of PCI can be affected by delays in transfer. Evidence suggests that antiplatelet therapy administered early, preferably in the ambulance during transfer, may provide better and earlier perfusion. Ticagrelor, a direct platelet P2Y12 receptor inhibitor, is indicated for the management of patients with acute coronary syndromes. The ATLANTIC study (NCT01347580; EudraCT 2011-000214-19) is a 30-day international, randomized, parallel-group, placebo-controlled study in male and female patients (aged ≥18 years) who are diagnosed as having STEMI, with intended primary PCI. In total, 1770 patients will be randomized immediately after diagnosis to prehospital administration of ticagrelor 180 mg followed by matching placebo administered in hospital, or prehospital administration of placebo followed by ticagrelor 180 mg administered in hospital. All patients will then receive ticagrelor 90 mg twice daily for 30 days. The coprimary end point is the percentage of patients reaching thrombolysis in myocardial infarction flow grade 3 in the infarct-related artery at initial angiography or achieving ≥70% ST-segment elevation resolution pre-PCI. The primary safety end point is major, life-threatening, or minor bleeding after ticagrelor administration. The results of this study may have an impact on future recommendations for treatment for patients with STEMI.

Prehospital treatment of ST-segment elevated myocardial infarction patients

Providing optimal care to patients with ST-segment elevated myocardial infarction is challenging. If a patient experiences chest pain and calls the emergency number, a cascade of actions is initiated that should lead to a diagnosis, start of treatment and reperfusion of the infarcted myocardium. This should all happen within 90 min after first medical contact, irrespective of the location of the patient or the time of day. The complex organization that is needed to achieve this goal in every ST-segment elevated myocardial infarction patient accounts for a fascinating interplay between prehospital and in-hospital care, in a situation when every minute counts. State-of-the-art care should be provided according to the latest insights and guidelines.