Intravenous iron therapy for patients with iron deficiency and heart failure: a systematic review and meta-analysis of randomized controlled trials

Introduction: Heart failure (HF) presents a significant health challenge, with intravenous (IV) iron therapy considered a potential treatment avenue. Method: We assessed IV iron therapy’s efficacy in HF patients with concurrent iron deficiency versus standard of care. Primary outcomes included the composite of HF hospitalizations or cardiovascular-related mortality, HF hospitalizations, and all-cause, HF, and cardiovascular mortality rates. Secondary measures encompassed improvements in New York Heart Association functional classification, quality of life, 6-minute walk test, left ventricular ejection fraction, and adverse events. We used a random-effects model to compute relative risk (RR) or mean difference (MD) with 95% confidence intervals (CIs). Results: Based on an analysis of 14 randomized controlled trials involving 6614 patients, IV iron therapy significantly reduced composite outcome (RR: 0.84, 95% CI: 0.73, 0.96; P = 0.01) and HF hospitalizations (RR: 0.74, 95% CI: 0.61, 0.89; P = 0.002) compared to standard of care. Mortality rates showed no significant difference. IV iron therapy improved New York Heart Association functional classification, quality of life, and 6-minute walk test, with no major impact on left ventricular ejection fraction. Adverse events remained stable. Conclusions: IV iron therapy holds promise for diminishing HF hospitalizations and enhancing quality of life and 6-minute walk test in HF patients. Yet, its effect on all-cause or cardiovascular mortalities appears limited.