Effect of a Restrictive vs Liberal Blood Transfusion Strategy on Major Cardiovascular Events Among Patients With Acute Myocardial Infarction and Anemia

Abstract

Anemia, with or without overt bleeding, is common in patients with acute myocardial infarction (AMI) and affects prognosis. Even moderate levels of anemia (hemoglobin level of 10-12 g/dL) are associated with increased cardiovascular mortality compared with normal hemoglobin values in the context of acute coronary syndromes.¹ Transfusion is often considered to be indicated when the hemoglobin level falls below 10 g/dL, with large variations in clinical practice due to lack of robust data. Observational studies have yielded conflicting results^2-4 and only 2 small randomized trials (including 45 and 110 patients) have compared restrictive with liberal transfusion strategies in this setting.^5,6 Large randomized trials have compared transfusion strategies in patients with gastrointestinal bleeding⁷ and those undergoing surgical procedures^8-10 and generally found benefit from a restrictive strategy, but these trials excluded patients with AMI.¹¹