In a post hoc analysis of Myocardial-IRON, treatment with ferric carboxymaltose improved left atrial longitudinal strain (LA-LS) in patients with HFrEF/HFmrEF and iron deficiency compared with placebo.

This summary is based on the publication of Santas E, del Canto I, Cardells I, et al. Improvement in left atrial strain following ferric carboxymaltose in heart failure: an analysis of the Myocardial-IRON trial - ESC Heart Fail. 2023 Dec 20. [Online ahead of print] doi: 10.1002/ehf2.14630

Introduction and methods

Background

Treatment with ferric carboxymaltose (FCM) has been shown to improve symptoms, quality of life and risk of hospital readmission in patients with iron deficiency (ID) and HFrEF [1-2]. There is great interest to understand the mechanisms underlying the clinical benefit of FCM in HF. In the Myocardial-IRON and IRON-CRT trials, treatment with FCM was associated with improvements in biventricular strain parameters and biventricular systolic function [3-5]. It is unclear whether treatment with FCM has beneficial effects on left atrium (LA) function.

Aim of the study

The aim of this post hoc analysis of Myocardial-IRON was to determine the effects of FCM treatment on LA longitudinal strain (LA-LS) in patients with HFrEF/HFmrEF.

Methods

This analysis included 29 patients with chronic HF, LVEF ≤50% and ID and without AF from the double-blind, placebo-controlled, multicenter, randomized Myocardial-IRON trial. Patients were randomized to intravenous FCM (n=12) or placebo (n=17), and CMR-FT studies were performed at baseline, day 7 and day 30.

Outcomes

The outcome of this subanalysis was the change in LA-LS at day 7 and day 30.

Main results

• After adjusting for baseline LA-LS, there was no difference in LA-LS at day 7 between the FCM group and placebo group (difference: - Δ 0.69%; P=0.112).
• Treatment with FCM improved LA-LS at day 30 compared with placebo (LA-LS was -12.0 ±0.5 in the FCM group and -8.5 ±0.6 in the placebo group; - Δ 3.55%; P<0.001).

Conclusion

In this post hoc analysis of Myocardial-IRON, treatment with FCM improved LA-LS as assessed with CMR-FT at 30 days in patients with HF with LVEF ≤50% and ID compared with placebo. The authors emphasize that “[f]urther work should confirm our findings and evaluate the potential benefits of iron repletion on LA function or remodelling in HF”.

Find this article online at ESC Heart Fail.

References

1. Anker SD, Kirwan BA, van Veldhuisen DJ, et al. Effects of ferric carboxymaltose on hospitalisations and mortality rates in iron-deficient heart failure patients: An individual patient data meta-analysis. Eur J Heart Fail 2018; 20: 125-133.

2. Ponikowski P, Kirwan BA, Anker SD, et al. Ferric carboxymaltose for iron deficiency at discharge after acute heart failure: A multicentre, double-blind, randomised, controlled trial. Lancet 2020; 396: 1895-1904.

3. del Canto I, Santas E, Cardells I, et al. Myocardial-IRON investigators. Short-term changes in left and right ventricular cardiac magnetic resonance feature tracking strain following ferric carboxymaltose in patients with heart failure: A substudy of the Myocardial-IRON trial. J Am Heart Assoc 2022; 11:e022214.

4. Martens P, Dupont M, Dauw J, et al. The effect of intravenous ferric carboxymaltose on cardiac reverse remodeling following cardiac resynchronization therapy—The IRON-CRT trial. Eur J Heart Fail 2021; 42: 4905-4914.

5. Martens P, Dupont M, Dauw J, et al. The effect of intravenous ferric carboxymaltose on right ventricular function. Insights from the IRON-CRT trial. Eur J Heart Fail 2022; 24: 1106-1113.