The article discusses the use of intravenous iron therapy in patients with heart failure with preserved ejection fraction (HFpEF). Iron deficiency is common in HFpEF and is associated with worse exercise capacity and quality of life. The article presents the results of a randomized controlled trial that evaluated the effects of intravenous ferric carboxymaltose (FCM) on exercise capacity in HFpEF patients with iron deficiency. The study found that patients receiving FCM showed a significant improvement in exercise capacity compared to those receiving a placebo. However, there was no significant difference between the groups in patient global assessment or health-related quality of life. The article emphasizes the need for further investigation and larger-scale trials to confirm the benefits of intravenous iron therapy in HFpEF.