European Ambulance Acute Coronary Syndrome (ACS) Angiography Trial

Inclusion Criteria: The decision to randomize participants was made by a qualified physician or paramedic who was present at the time. Participants were included in the study if they presented either via ambulance or to a center where PCI was not performed and met all of the following criteria: 1. Provided written informed consent before initiation of any study related procedures. Participants randomized in the ambulance may initially have signed an abridged version. 2. Aged ≥18 years at the time of randomization. 3. Had a presumed diagnosis of STE-ACS with onset of symptoms of \>20 minutes and \<12 hours with one or more of the following: * ST segment elevation of ≥1 millimeters (mm) in ≥2 contiguous leads * Presumably new left bundle branch block * An infero-lateral myocardial infarction with ST segment depression of ≥1 mm in ≥2 of leads V1-3 with a positive terminal T wave 4. All participants would proceed with emergent angiography and primary PCI if indicated \<2 hours after first medical contact Exclusion Criteria: Participants were excluded from the study if any of the following exclusion criteria applied prior to randomization: 1. Any bleeding diathesis or severe hematological disease or history of intra-cerebral mass, aneurysm, arterio-venous malformation, hemorrhagic stroke, intra-cranial hemorrhage, or gastrointestinal or genitourinary bleeding within the last 2 weeks. 2. Participants who had undergone recent surgery (including biopsy) within the last 2 weeks. 3. Participants who were on warfarin (not applicable if International Normalized Ratio known to be \<1.5). 4. Participants who had received UFH, LMWH, or bivalirudin immediately before randomization. 5. Thrombolytic therapy within the last 48 hours. 6. Absolute contra-indications or allergy that could not be pre-medicated to iodinated contrast or to any of the study medications including aspirin or clopidogrel. 7. Contraindications to angiography, including but not limited to severe peripheral vascular disease. 8. If it was known, pregnant or nursing mothers. Women of child-bearing age were asked if they were pregnant or thought that they may be pregnant. 9. If it is known, a creatinine clearance \<30 milliliter/minute or dialysis dependent. 10. Previous enrolment in this study. 11. Treatment with other investigational drugs or devices within the 30 days preceding randomization or planned use of other investigational drugs or devices in this trial. 12. Participants may not have been enrolled if the duration of randomized investigational medicinal product anti-thrombin infusion was likely to be \<30 minutes from the time of onset to the commencement of angiography. 13. Participants may not have been enrolled within a primary PCI-capable hospital (unless at the time of randomization, the catheter laboratory was not available, and the participant required transfer to another primary PCI capable hospital). 14. Estimated body weight of \>120 kg