OBJECTIVES: To determine whether RBC transfusion increases in-vivo platelet aggregation and inflammation in coronary and non-coronary patients.<br /><br />BACKGROUND: Red blood cell (RBC) transfusion increases in-vitro platelet activation and aggregation in healthy volunteers, providing a possible explanation for the increase in recurrent ischemic events and mortality reported after RBC transfusion in ACS patients.<br /><br />METHODS: Platelet reactivity was measured before and after RBC transfusion in 61 patients (33 ACS patients and 28 non-ACS patients). Relative changes between baseline and post-transfusion measurements of maximum (MPA) and residual platelet aggregation (RPA) were considered with different agonists as well as changes in Vasodilatator-Stimulated Phosphoprotein Platelet Reactivity Index (VASP-PRI) and P-selectin expression. Inflammatory and thrombotic biomarkers were also measured before and after transfusion.<br /><br />RESULTS: After RBC transfusion, platelet reactivity was increased when measured with adenosine diphosphate (ADP)-induced light transmission aggregometry (+11.6% relative increase of MPA; p = 0.004 and +10.8% increase of RPA; p = 0.005) and VASP PRI (relative increase of +20.7%; p=0.002) while there was a non-significant trend towards an increase of P-selectin expression. Similar results were found with the non-specific agonist thrombin receptor activated peptide (TRAP) (relative increase of +11.7% for MPA p=0.04 and+12.7% for RPA; p=0.02) but not with collagen or arachidonic acid agonists. There were no significant differences in inflammatory and thrombotic biomarkers before and after transfusion.<br /><br />CONCLUSIONS: After red blood cell transfusion, there is an increase in platelet reactivity, especially with tests measuring the ADP-P2Y12receptor pathway without significant variation in inflammatory or thrombotic biomarkers. This in-vivo effect may account for the excess in ischemic events observed in the context of ACS treated by PCI and P2Y12inhibitors.
Silvain, J., Abtan, J., Kerneis, M., Martin, R., Finzi, J., Vignalou, J.-B., … Montalescot, G. (2014). Impact of Red Blood Cell Transfusion on Platelet Aggregation and Inflammatory Response in Anemic Coronary and Noncoronary Patients. Journal of the American College of Cardiology, 63(13), 1289–1296. https://doi.org/10.1016/j.jacc.2013.11.029