Intravenous Iron in Heart Failure Patients With Iron Deficiency: A Meta-Analysis of Randomized Controlled Trials

The impact of intravenous iron therapy in heart failure (HF) patients with iron deficiency (ID) is still controversial.

We performed an extensive search of electronic databases for pertinent studies, encompassing all records up to March 4, 2024. Using random-effects models in a meta-analysis, the collected outcomes data were then synthesized and analyzed.

Fourteen trials with 7786 participants (iron therapy: n = 3994; control: n = 3792) were included. Intravenous iron therapy can decrease the risk of composite events of total hospitalization for HF and cardiovascular (CV) death (RR = 0.82 [0.72, 0.92]), total hospitalization for HF (RR = 0.78 [0.66, 0.91]), first hospitalization for HF and CV death (OR = 0.78 [0.65, 0.93]), CV death (OR = 0.86 [0.76, 0.98]), first hospitalization for HF(OR = 0.77 [0.61, 0.99]), but not significantly reduce the risk of all-cause mortality (OR = 0.93 [0.83, 1.04]). Furthermore, intravenous iron treatment can improve the distance of 6-min walking test (6MWT) (WMD = 18.99 [7.41, 30.57]). Subgroup analyses found that intravenous iron may be more beneficial in HF patients with transferrin saturation (TSAT) <20%, and those with ischemic heart disease. Meta-regression analysis revealed that baseline hemoglobin levels served as a significant moderator of the therapeutic efficacy of intravenous iron supplementation.

For HF patients with ID, intravenous iron therapy can decrease the risk of hospitalization for HF, CV death and improve their exercise capacity. Patients with ischemic cardiomyopathy or with TSAT <20% may derive greater benefit from intravenous iron therapy.