Red blood cell storage duration and mortality in patients undergoing percutaneous coronary intervention Simon D. Robinson, MBChB, MD, a Christian Janssen, PhD, a,b Eric B. Fretz, MD, a Brian Berry, MD, a Alex J. Chase, MBChB, PhD, c Anthony Della Siega, MD, a Ronald G. Carere, MD, d Anthony Fung, MBBS, e Gerald Simkus, MD, f W. Peter Klinke, MD, a and J. David Hilton, MD a Victoria BC, Vancouver BC, New Westminster BC, and Alberta, Canada; and Swansea, Wales, UK Background Blood transfusion has been associated with an increased mortality in patients undergoing percutaneous coronary intervention (PCI). Although the reasons for this remain unclear, it may be related to the structural and functional changes occurring within red blood cells (RBCs) during storage. We investigated whether RBC storage duration was associated with mortality in patients requiring transfusion after PCI. Methods We collected data on all RBC transfusions occurring within 10 days of PCI (excluding those related to cardiac surgery) using the British Columbia Cardiac Registry and Central Transfusion Registry. Transfusion details were analyzed according to 30-day survival. Results From a total of 32,580 patients undergoing PCI, 909 (2.8%) patients received RBCs with a mean storage duration of 25 ± 10 days. In these 909 patients, mean transfusion volumes were lower in survivors (2.8 ± 2.1 vs 3.8 ± 2.9 U, P = .002) than those who died within 30 days. In a multivariate analysis to adjust for baseline risk, mean RBC storage age (HR 1.02 [95% CI 1.01-1.04], P = .002) and transfusion volume (HR 1.26 [95% CI 1.18-1.34], P b .001) both predicted 30-day mortality. Transfused patients who received only older blood (RBC min age N28 days) appeared to be at greater risk of death (HR 2.49 [95% CI 1.45-4.25], P = .001). Conclusion Red blood cell transfusion is associated with increased 30-day mortality in patients undergoing PCI. Although current transfusion practice permits RBC storage for up to 42 days, the use of older red cells may pose an additional hazard to this patient group. (Am Heart J 2010;159:876-81.) Background Percutaneous coronary intervention (PCI) along with anti-thrombotic and anti-platelet pharmacotherapies im- prove outcomes in patients with coronary artery disease especially those presenting with acute coronary syn- dromes. 1,2 However, each of these strategies confers an increased risk of periprocedural bleeding 3 with major bleeding being associated with a significant increase in the risk of death within 30 days. 4,5 Despite being widely used to treat blood loss, blood transfusion appears harmful in patients with coronary artery disease, 4 including those undergoing PCI 5 and cardiac surgery. 6 Although the reasons for this may be multi-factorial, 7 it has been suggested that this may in part be due to structural and functional changes occurring within red blood cells (RBCs) during storage. 8 These ex vivo changes are incompletely understood but have been related to decreased myocardial oxygen delivery 9 and nitric oxide bioavailability 10 following transfusion of older blood. There are conflicting data on the magnitude and time course for RBC degradation with well charac- terized changes occurring both early and late during storage. Previous work using an animal model found reduced survival following transfusion with red cells stored for N28 days, 11 and although not directly comparable to humans, patients receiving older blood may be at the greatest risk from deleterious storage related changes within RBCs. Longer RBC storage durations have previously been linked to increased morbidity and mortality in critically ill From the a Victoria Heart Institute Foundation, Victoria BC, Canada, b University of Alberta, Alberta, Canada, c Morriston Cardiac Centre, Swansea, Wales, UK, d St Paul's Hospital, Vancouver BC, Canada, e Vancouver General Hospital, Vancouver BC, Canada, and f Royal Columbian Hospital, New Westminster BC, Canada. Grant Support Victoria Foundation (Canadian Charity No. 130650898RR0001). Submitted November 9, 2009; accepted February 22, 2010. Reprint requests: Simon Robinson, MBChB, MD, Victoria Heart Institute Foundation 200- 1900 Richmond Avenue, Victoria, BC, Canada V8R 4R2. E-mail: sdrobinson@vhif.org 0002-8703/$ - see front matter © 2010, Mosby, Inc. All rights reserved. doi:10.1016/j.ahj.2010.02.018