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

One-Year Mortality for Bivalirudin vs Heparins Plus Optional Glycoprotein IIb/IIIa Inhibitor Treatment Started in the Ambulance for ST-Segment Elevation Myocardial Infarction: A Secondary Analysis of the EUROMAX Randomized Clinical Trial

Importance

Uncertainty exists regarding potential survival benefits of bivalirudin compared with heparin with routine or optional use of glycoprotein IIb/IIIa inhibitors (GPIs) in patients with ST-segment elevation myocardial infarction (STEMI). Few data are available regarding long-term mortality in the context of contemporary practice with frequent use of radial access and novel platelet adenosine diphosphate P2Y12 receptor inhibitors.

Objective

To assess the effect of bivalirudin monotherapy compared with unfractionated or low-molecular-weight heparin plus optional GPIs on 1-year mortality.

Design, Setting, and Participants

This international, randomized, open-label clinical trial (EUROMAX [European Ambulance Acute Coronary Syndrome Angiography]) included 2198 patients with STEMI undergoing transport for primary percutaneous coronary intervention from March 10, 2010, through June 20, 2013, and followed up for 1 year. Patients were randomized (1:1) in ambulance to bivalirudin monotherapy vs unfractionated or low-molecular-weight heparin plus optional GPIs (control group). Analysis was based on intention to treat.

Main Outcomes and Measures

The primary outcome of this prespecified analysis was 1-year mortality. All deaths were adjudicated as cardiac or noncardiac by an independent, blinded clinical events committee. One-year mortality was assessed and examined across multiple prespecified subgroups.

Results

Of the 2198 patients enrolled (1675 men [76.2%] and 523 women [23.8%]; median [interquartile range] age, 62 [52-72] years), complete 1-year follow-up data were available for 2164 (98.5%). All-cause 1-year mortality occurred in 118 patients (5.4%). The number of all-cause deaths was the same for both treatment groups (59 deaths; relative risk [RR], 1.02; 95% CI, 0.72-1.45; P = .92). No differences were noted in the rates of 1-year cardiac death (44 [4.0%] for the bivalirudin group vs 48 [4.3%] for the control group; RR, 0.93; 95% CI, 0.63-1.39; P = .74) or noncardiac death (15 [1.4%] for the bivalirudin group vs 11 [1.0%] for the control group; RR, 1.39; 95% CI, 0.64-3.01; P = .40). Results were consistent across the prespecified patient subgroups. The rate of deaths occurring from 30 days to 1 year was also similar (27 [2.5%] in the bivalirudin group vs 25 [2.3%] in the control group; RR, 1.10; 95% CI, 0.64-1.88; P = .73).

Conclusions and Relevance

In patients with STEMI who were being transported for primary percutaneous coronary intervention, treatment with bivalirudin or with heparin with optional use of GPI resulted in similar 1-year mortality. The reduced composite end point of death and/or major bleeding at 30 days in the bivalirudin arm of the EUROMAX trial did not translate into reduced cardiovascular or all-cause death at 1 year.

Trial Registration

clinicaltrials.gov Identifier: NCT01087723.

Comparison between patients included in randomized controlled trials of ischemic heart disease and real-world data. A nationwide study

BACKGROUND

The objective was to compare patients with ischemic heart disease (IHD) undergoing percutaneous coronary intervention (PCI) who were included in randomized controlled trials (RCTs) (trial participants) with patients who were not included (nonparticipants) on a trial-by-trial basis and according to indication for PCI.

METHODS

In this cohort study, we compared patients with IHD who were randomized in RCTs in relation to undergoing PCI in Denmark between 2011 and 2015 were considered as RCT-participants in this study. The RCT-participants were compared with contemporary nonparticipants with IHD undergoing PCI in the same period, and they were identified using unselected national registry data. The primary end point was all-cause mortality.

RESULTS

A total of 10,317 (30%) patients were included in 10 relevant RCTs (trial participants), and a total of 23,644 (70%) contemporary patients did not participate (nonparticipants). In all the included RCTs, nonparticipants had higher hazard ratios for mortality compared to trial participants (P < .001). Among all patients treated with PCI, the pooled estimates showed a significantly higher mortality rate for nonparticipants compared to trial participants (hazard ratio: 2.03, 95% CI: 1.88-2.19) (P < .001). When patients were stratified according to indication for PCI, the pooled estimates showed a significantly lower mortality rate for trial participants compared to nonparticipants in all strata (P for all < .001).

CONCLUSIONS

Trial participants in recently performed RCTs including patients undergoing PCI were not representative of the general population of patients with IHD treated with PCI according to clinical characteristics and mortality. The difference in mortality was found irrespective of the indication for PCI. Thus, results from RCTs including patients undergoing PCI should be extrapolated with caution to the general patient population.

Outcomes in elderly and young patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention with bivalirudin versus heparin: Pooled analysis from the EUROMAX and HORIZONS-AMI trials

BACKGROUND

Since older age is a strong predictor of not only bleeding but also of ischemic events, understanding the risk:benefit profile of bivalirudin in the elderly undergoing primary percutaneous coronary intervention (pPCI) for ST-segment elevation (STEMI) is important. For this, we aim to compare elderly with young patients, who all underwent pPCI for STEMI and randomly received either bivalirudin or heparin.

METHODS

We performed a patient-level pooled analysis (n=5800) of two large randomized trials. A total of 2149 (37.1%) elderly patients (>65 years of age) with STEMI were enrolled and randomly assigned to either bivalirudin or heparin with or without a GPI (control group) before pPCI. Clinical outcomes at 30 days were analyzed.

RESULTS

In elderly patients, bivalirudin significantly reduced non-CABG major bleeding (7.1% vs 10.4%; P<.01), subacute ST (0.4% vs 1.5%; P<.01), and net adverse clinical events (NACE; composite of all-cause mortality, reinfarction, IDR, stroke or protocol-defined non-CABG major bleeding [13.7% vs 17.2%; P=.03]) with comparable rates of stroke, MI, acute ST, or all-cause death, when compared with heparin with or without GPI.

CONCLUSIONS

In a large group of elderly patients enrolled in the EUROMAX and HORIZONS-AMI trials, bivalirudin was associated with lower 30-day rates of non-CABG major bleeding, subacute ST and NACE, with similar 30-day rates of acute ST and mortality.

Assessment of consent models as an ethical consideration in the conduct of prehospital ambulance randomised controlled clinical trials: a systematic review

BACKGROUND

We sought to understand the main ethical considerations when conducting clinical trials in the prehospital ambulance based setting.

METHODS

A systematic review of the literature on randomised controlled trials in ambulance settings was undertaken. A search of eight databases identified published studies involving recruitment of ambulance service users. Four independent authors undertook abstract and full-text reviews to determine eligibility and extract relevant data. The data extraction concentrated on ethical considerations, with any discussion of ethics being included for further analysis. The resultant data were combined to form a narrative synthesis.

RESULTS

In all, 56 papers were identified as meeting the inclusion criteria. Issues relating to consent were the most significant theme identified. Type of consent differed depending on the condition or intervention being studied. The country in which the research took place did not appear to influence the type of consent, apart from the USA where exception from consent appeared to be most commonly used. A wide range of terms were used to describe consent.

CONCLUSIONS

Consent was the main ethical consideration in published ambulance based research. A range of consent models were used ranging from informed consent to exception from consent (waiver of consent). Many studies cited international guidelines as informing their choice of consent model but diverse and sometimes confused terms were used to describe these models. This suggests that standardisation of consent models and the terminology used to describe them is warranted.

Impact of acute infarct-related artery patency before percutaneous coronary intervention on 30-day outcomes in patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention in the EUROMAX trial

AIMS

Early infarct-related artery patency has been associated with improved outcomes in patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention. However, it is unknown whether this relationship persists in contemporary practice with pre-hospital initiation of treatment, use of novel P2Y₁₂ inhibitors and frequent use of drug-eluting stents. The purpose of the study was to determine the impact of early infarct-related artery patency on outcomes in the contemporary EUROMAX trial.

METHODS AND RESULTS

A total of 2218 patients were enrolled. The current analysis was done on 1863 patients who underwent percutaneous coronary intervention and had infarct-related artery patency data. Thirty-day outcomes were compared according to infarct-related artery flow before percutaneous coronary intervention (Thrombolysis in Myocardial Infarction (TIMI) flow 0/1 vs. TIMI flow 2/3), and interaction with antithrombotic strategy was examined. A patent infarct-related artery (TIMI flow 2/3) was present in 707 patients (37.9%) and was associated with a higher rate of final TIMI 3 flow grade (98.9 vs. 92.6%; p<0.001). At 30 days, a patent infarct-related artery was associated with lower rates of cardiac death (1.3% vs. 2.9%; p=0.026) and the composite of death or myocardial infarction (2.7% vs. 4.6%; p=0.039). There were no interactions between antithrombotic treatment and the impact of infarct-related artery patency on cardiac death, myocardial infarction, or the composite of death or myocardial infarction (Breslow-Day interaction p-values of 0.21, 0.33 and 0.46, respectively).

CONCLUSION

Despite evolution in primary percutaneous coronary intervention strategies, early infarct-related artery patency is still associated with higher procedural success and improved clinical outcomes. The choice of antithrombotic strategy did not interact with the benefits of a patent infarct-related artery at presentation.

Impact of arterial access site on outcomes after primary percutaneous coronary intervention: prespecified subgroup analysis from the EUROMAX trial

BACKGROUND

In European Ambulance Acute Coronary Syndrome Angiography (EUROMAX), bivalirudin improved 30-day clinical outcomes with reduced major bleeding compared with heparins plus optional glycoprotein IIb/IIIa inhibitors. We assessed whether choice of access site (radial or femoral) had an impact on 30-day outcomes and whether it interacted with the benefit of bivalirudin.

METHODS AND RESULTS

In EUROMAX, choice of arterial access was left to operator discretion. Overall, 47% of patients underwent radial and 53% femoral access. Baseline risk was higher in the femoral access group. Unadjusted proportions for the primary outcome (death or noncoronary artery bypass graft protocol major bleeding at 30 days) were lower with radial access, however, without differences in major or major plus minor bleeding proportions. After multivariable adjustment, ischemic outcomes were no longer different between access site groups, except for a lower risk of stroke in radial patients. Bivalirudin was associated with lower proportions of the primary outcome in both the radial (odds ratio, 0.58; 95% CI, 0.33-1.03; P=0.058) and the femoral groups (odds ratio, 0.59; 95% CI, 0.37-0.93; P=0.022; interaction P=0.97). Bleeding was significantly lower in the bivalirudin group both in the radial- and femoral-treated patients but no significant difference was observed in ischemic outcomes. In multivariable analysis, bivalirudin emerged as the only independent predictor of reduced major bleeding (odds ratio, 0.45; 95% CI, 0.27-0.74; P=0.002).

CONCLUSIONS

In this prespecified analysis from EUROMAX, radial access was preferred in lower risk patients and did not improve clinical outcomes. Bivalirudin was associated with less bleeding irrespective of access site.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01087723.

ST-segment resolution with bivalirudin versus heparin and routine glycoprotein IIb/IIIa inhibitors started in the ambulance in ST-segment elevation myocardial infarction patients transported for primary percutaneous coronary intervention: The EUROMAX ST-segment resolution substudy

BACKGROUND

Myocardial reperfusion after primary percutaneous coronary intervention (PCI) can be assessed by the extent of post-procedural ST-segment resolution. The European Ambulance Acute Coronary Syndrome Angiography (EUROMAX) trial compared pre-hospital bivalirudin and pre-hospital heparin or enoxaparin with or without GPIIb/IIIa inhibitors (GPIs) in primary PCI. This nested substudy was performed in centres routinely using pre-hospital GPI in order to compare the impact of randomized treatments on ST-resolution after primary PCI.

METHODS

Residual cumulative ST-segment deviation on the single one hour post-procedure electrocardiogram (ECG) was assessed by an independent core laboratory and was the primary endpoint. It was calculated that 762 evaluable patients were needed to show non-inferiority (85% power, alpha 2.5%) between randomized treatments.

RESULTS

A total of 871 participated with electrocardiographic data available in 824 patients (95%). Residual ST-segment deviation one hour after PCI was 3.8±4.9 mm versus 3.9±5.2 mm for bivalirudin and heparin+GPI, respectively ( p=0.0019 for non-inferiority). Overall, there were no differences between randomized treatments in any measures of ST-segment resolution either before or after the index procedure.

CONCLUSIONS

Pre-hospital treatment with bivalirudin is non-inferior to pre-hospital heparin + GPI with regard to residual ST-segment deviation or ST-segment resolution, reflecting comparable myocardial reperfusion with the two strategies.

Comparison of anti-thrombotic strategies using Bivalirudin, Heparin plus Glycoprotein IIb/IIIa inhibitors and Unfractionated Heparin Monotherapy for patients undergoing percutaneous coronary intervention - A single centre observational study

AIMS

The study was planned to compare Anti-thrombotic strategies for patients undergoing PCI in a real world population with an emphasis on occurrence of major bleeding, composite ischemic end points and economic outcomes.

METHODS

The present study is a single center, prospective, observational study in consecutive patients undergoing PCI at Fortis Escorts Heart Institute (FEHI) and describes Authors' experience with three different Anti-Thrombotic Strategies in a real world population. Patients were consecutively enrolled in the study and the choice of Anti-thrombotic strategy was left to individual operator(s) based on their own clinical judgment and patient's affordability. No specific inclusion/exclusion criteria were specified on the choice of Anti-Thrombotic Strategy.

RESULTS

A total 1453 patients were consecutively enrolled into the study and were followed telephonically after 30 days. 252 patients were treated with Bivalirudin (Angiomax) during PCI (17.3%), 430 (29.6%) patients were treated with Heparin plus GPI & remaining 771 (53.1%) were treated with Heparin monotherapy. Incidence of major bleeding was lowest in patients treated with Bivalirudin (1.59%) when compared to Heparin plus GPI (3.49%) and Heparin monotherapy (5.97%), p = 0.005 Bivalirudin vs. Heparin Monotherapy, and p = 0.145, Bivalirudin vs. Heparin + GPI. No bleeding was observed in STEMI patients treated with Bivalirudin compared to 7.4% in patients treated with GPI and 14.3% in patients treated with UFH. Similarly non-access site bleeding was lowest in patients treated with Bivalirudin. Only 4 patients (1.6%) treated with Bivalirudin required Blood transfusion compared to 25 in Heparin plus GPI (5.8%) and 38 (5%) in Heparin Monotherapy arm. In Composite Ischemic end-points, no "All-cause Mortality" was observed in Bivalirudin group compared to 2.8% in Heparin plus GPI. Early stent thrombosis was seen in 1 patient with Heparin plus GPI and none with Heparin monotherapy and Bivalirudin group. None of the patients underwent TLR (target lesion revascularization) and TVR (target vessel revascularization) within 30 days post procedure other than one early stent thrombosis reported with Heparin plus GPI. Cost of blood product transfusion was lower with Bivalirudin as compared to Heparin plus GP IIb/IIIa arm (p = 0.01) and with Heparin alone (p = 0.001). Due to lower complications including blood transfusions and reduced hospital stay in Bivalirudin group, these benefits outweigh the incremental cost due to higher acquisition cost of the drug.

CONCLUSION

Bivalirudin use during PCI is associated with a distinct advantage of having lower access site and non-access site bleeding without compromising on the efficacy. We observed a reduction in blood transfusions, hospital stay and mortality for patients treated with Bivalirudin compared with Heparin plus GPI or Heparin Monotherapy. Bivalirudin can be safely adopted into our Institutional protocol for the treatment of high risk PCI such as STEMI, ACS, and Complex elective PCI.

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.