In the Journal of the American College of Cardiology, Silvain and colleagues report that RBC transfusion increased platelet reactivity in anemic patients, including 33 patients with acute coronary syndrome (ACS).
They found that platelet aggregation increased by ~11% after transfusion (p=0.004) and by >20% (p=0.002) when measuring the P2Y12 receptor pathway using ADP-induced aggregometry. No significant differences were found in inflammatory and thrombotic markers or the length of RBC storage. These findings suggest that RBC transfusion might increase platelet reactivity through activation of the P2Y12 platelet receptor or within the ADP pathway, and caution against liberal transfusion of anemic patients with ACS. In an adjoining editorial, Rao and Sherwood stress the need for a randomized control trial of conservative verses liberal treatment of anemic patients with ACS since about 10% of patients (or 130,000) with ACS receive RBC transfusions annually.