Acute coronary syndromes (ACS), with or without ST segment elevation, are a frequent complication of atherothrombosis and are responsible for a high number of hospitalisations and interventions; thus, they represent a considerable burden on healthcare systems, and on society in general. ACS result from the rupture of an atherosclerotic plaque, leading to activation of the coagulation cascade and platelet functions, and subsequent thrombus formation, and myocardial ischaemia/necrosis. In both instances, once constituted, ACS can result in death, recurrence of myocardial infarction (MI), or stroke, with frequency depending on the initial clinical setting. In ST elevation MI, the risk is much higher during the first 30 days of evolution as compared to non-ST elevation ACS (NSTE-ACS), but at 1 year the risk is identical in both presentations. Over the last 20 years, the outcome of ACS has considerably improved, thanks to a better pharmacological environment, and to the use of reperfusion and/or revascularisation. Indeed, both forms of ACS require the same type of treatment, which includes potent antiplatelet agents, anticoagulants, anti-ischaemic agents, urgent reperfusion with thrombolysis or percutaneous coronary intervention (PCI) in ST elevation MI, and revascularisation in NSTE-ACS.

Indeed, the use of multiple antiplatelet agents or anticoagulants combined with revascularisation has led to an increased risk of bleeding complications. Until recently, bleeding was thought to be inherent to the modern therapeutic approach to ACS, and was seen as the price to pay for an improvement in outcome. Bleeding complications were more or less considered to be a non-event that could easily be fixed with appropriate measures, and blood transfusion if needed. However, it has recently been shown that bleeding has a strong impact on the risk of death, MI and stroke in patients with ACS. In addition, the role of transfusion has come under fire, since it may actually have …