Silvain J, et al. - In this substudy including a total of 129 percutaneous coronary intervention (PCI) treated ST-segment elevation myocardial infarction (STEMI) patients who were randomly allocated to intravenous enoxaparin (n = 58) or unfractionated heparin (UFH, n = 71) in the ATOLL randomized trial, researchers compared the peri-procedural biomarkers of coagulation and platelet activation. Findings revealed more frequently achieved therapeutic levels with enoxaparin than UFH during primary PCI. Results also demonstrated more frequent occurrence of ischemic events in relation to higher level of thrombin generation measured at the end of the PCI procedure.