Single Iron Infusion Improves Exercise Capacity in Heart Failure Patients

A single intravenous iron treatment could help people living with a common form of heart failure regain physical strength and improve their ability to exercise, according to promising new clinical research from Mass General Brigham in the United States. The IRON-MET HFpEF trial involved 65 patients with heart failure with preserved ejection fraction (HFpEF), a condition in which the heart becomes less able to relax and fill properly despite maintaining a relatively normal pumping percentage. Participants also had iron deficiency, which can contribute to fatigue and reduced exercise tolerance. Researchers gave 44 patients a single 1,000 mg infusion of ferric derisomaltose, while 21 received a placebo. After 12 weeks, those receiving iron experienced an approximately 10% improvement in peak oxygen uptake, an important measure of cardiovascular fitness, while the placebo group showed no meaningful change. Improvements were also observed in walking distance and certain measures of physical function, although overall patient-reported health scores did not significantly differ between groups. No serious treatment-related adverse events were reported. Scientists believe correcting iron deficiency could provide a valuable additional treatment for selected heart failure patients, but larger trials are needed to determine whether the improvements last and translate into fewer hospitalisations or better long-term outcomes.