Postoperative Intravenous Ferric Derisomaltose for Prevention of Long-term Anemia After Cardiac Surgery

Postoperative anemia is highly prevalent among patients undergoing cardiac surgery and is associated with delayed functional recovery, increased morbidity, and impaired long-term outcomes. Preoperative iron deficiency is common in this population and contributes to inadequate erythropoietic recovery after surgery. Functional iron deficiency frequently develops even in patients without preoperative deficiency due to blood loss, hemodilution, and inflammation-mediated disruption of iron homeostasis. Despite this clinical burden, standardized strategies for postoperative anemia management have not been established. This prospective, randomized, double-blind, placebo-controlled clinical trial evaluates whether early postoperative intravenous iron supplementation improves long-term anemia outcomes in patients undergoing cardiac surgery with cardiopulmonary bypass. Adult patients with preoperative anemia (hemoglobin \<13 g/dL) or iron deficiency (ferritin \<100 ng/mL or transferrin saturation \<20%) will be screened. Eligible participants with postoperative day (POD) 1 hemoglobin \<10 g/dL will be randomized in a 1:1 ratio to receive either ferric derisomaltose (20 mg/kg, maximum 1,000 mg) or a matched placebo administered intravenously over 30 minutes on POD 1. All perioperative management outside the intervention follows current institutional standards. The primary outcome is the incidence of anemia at 6 months following surgery. Secondary outcomes include perioperative hemoglobin trends, functional recovery assessed by cardiopulmonary exercise testing and the 6-minute walk test at 6 months, transfusion requirements, postoperative complications including MAKE-90 and STS major morbidity, and changes in biomarkers of erythropoiesis and iron metabolism (erythroferrone, erythropoietin, hepcidin, and iron profile). Blood samples for biomarker analysis are collected at predefined perioperative timepoints. Ferric derisomaltose allows high-dose single-session iron repletion