Left ventricular ejection fraction recovery in patients with heart failure treated with intravenous iron: a pilot study

AimsIn patients with heart failure with reduced ejection fraction (HFrEF) and iron deficiency, treatment with intravenous iron has shown a clinical improvement regardless of anaemic status. Cardiac magnetic resonance (CMR) T2* sequence has shown a potential utility for evaluating myocardial iron deficiency. We aimed to evaluate whether T2* sequence significantly changes after ferric carboximaltose (FCM) administration, and if such changes correlate with changes in left ventricle ejection fraction (LVEF). Methods and resultsIn this pilot study, we included eight patients with chronic symptomatic (New York Heart Association II-III) HFrEF and iron deficiency. A CMR, including T2* analysis, was performed before and at a median of 43days (interquartile range=35-48) after intravenous FCM administration. Pearson or Spearman correlation coefficient (r) was used for bivariate contrast as appropriate. A partial correlation analysis was performed between LVEF and T2* while controlling for anaemia status at baseline. Anaemia was present in half of patients. After FCM administration, T2* decreased from a median of 39.5 (35.9-48) to 32ms (32-34.5), P=0.012. Simultaneously, a borderline increase in median of LVEF [40% (36-44.5) to 48.5% (38.5-53), P=0.091] was registered. In a bivariate correlational analysis, T2* was highly correlated with LVEF (r=-0.747, P=0.033). After controlling for anaemia at baseline, the association between T2* and LVEF persisted [r(partial): -0.865, R-2(partial): 0.748, P=0.012]. A median regression analysis backed-up these findings. ConclusionsIn a small sample of patients with HFrEF and iron deficiency, myocardial iron repletion assessed by CMR was associated to left ventricular remodelling. Further studies are warranted.