Anaemia and transfusion

Anaemia, irrespective of the cause-whether linked to, or worsened by, bleeding or phlebotomy, has an unfavourable impact on outcome, in terms of death and myocardial infarction, in acute coronary syndromes. In addition, it is an independent predictor of the risk of bleeding. The treatment of anaemia includes a search for the cause and its mechanism, blood transfusion, and iron therapy. Erythropoietin-stimulating agents are contraindicated. Blood transfusion should be considered with caution. It is indicated in cases of haemodynamic or ischaemic instability. However, in stable patients, blood transfusion should not be administered in patients with a haematocrit of >25%, since deleterious effects of transfusion have been described in this situation. For haematocrit below 25%, blood transfusion should be administered. Target post-transfusion haemoglobin levels are in the range of 9–10 g/dL. In practical terms, the risks of further ischaemic events and bleeding have to be assessed on a case-by-case basis in every patient admitted for acute coronary syndrome. Pharmacotherapy and invasive strategies have to be customized, depending on the ischaemic and bleeding risks, bearing in mind that those patients at highest risk of further ischaemic events are often the same patients who are at highest bleeding risk.