OR6-3 | Outcomes of Liberal Versus Restrictive Red Blood Cell Transfusion Strategies in Patients With Acute Myocardial Infarction: A Meta-Analysis

Anemia is a prevalent finding in patients with acute myocardial infarction (AMI), propagated by antithrombotic therapy, comorbidities, and procedural complications. Amongst patients with AMI, indications for red blood cell transfusion remain controversial, with prior studies noting conflicting results. We aim to evaluate clinical outcomes of liberal versus restrictive (conservative) transfusion strategies in AMI. We searched several databases for randomized controlled trials (RCTs) comparing liberal versus restrictive transfusion strategies in patients with AMI complicated by anemia. We used a common-effect model to calculate risk ratios (RR) with 95% confidence intervals in R studio. Outcomes assessed were all-cause mortality, heart failure, recurrent myocardial infarction, revascularization, and stroke. A total of 3 RCTs were identified consisting of 4215 patients with AMI of which 2100 were transfused under liberal criteria and 2115 were transfused under restrictive criteria. There were no significant differences between liberal versus restrictive transfusion strategies in all-cause mortality (RR 0.89; 95% CI 0.73 - 1.08), heart failure (RR 1.15; 95% CI 0.90 - 1.46), recurrent myocardial infarction (RR 0.87; 95% CI 0.70 - 1.08), revascularization (RR 0.94; 95% CI 0.63 - 1.41), and stroke (RR 0.88; 95% CI 0.53 - 1.45). In patients with AMI complicated by anemia, this meta-analysis found liberal red blood cell transfusion strategies were associated with similar outcomes compared to restrictive transfusion strategies. Further RCTs with increased sample sizes are warranted to confirm these findings.