Global longitudinal strain improvement after iron replacement in stable heart failure patients – FER-Strain study

Abstract

Background Iron deficiency in patients with heart failure with reduced left ventricular ejection fraction (LVEF) confers a poor prognosis in terms of hospital admissions and mortality, worsening functional class and quality of life. Its replacement with ferric carboxymaltose (FCM) has demonstrated to improve clinical parameters, however, the way it is achieved remains unclear. Improvement of myocardial contractility is proposed as possible hypothesis and global longitudinal strain (GLS) could behave as an early and high sensitive parameter to assess this improvement in myocardial deformation due to increased iron availability after replacement of iron deficiency. Purpose Evaluate the effect of replacement of iron deficiency with FCM on left ventricular global longitudinal strain in patients with stable heart failure with left ventricular ejection fraction <50%. Methods Observational, analytical, longitudinal and prospective study that enrolled 45 patients with stable heart failure with LVEF <50% who presented iron deficiency without anemia defined as serum ferritin <100 μg/L or between 100 and 300 μg/L and the transferrin saturation <20%. Transthoracic echocardiogram, 3D, tissue Doppler imaging and strain were performed, by the same cardiologist, before and four weeks after the iron deficiency replacement with FCM. Results The study population's median age was 71 years, 67% were men, 76% had high blood pressure, 62% dyslipemia and 33% diabetes. At baseline they presented LVEF 32% ±8.75%, LV systolic volume index 62.3ml±29.56ml and LV GLS −9.09%±3.44%. Four weeks after iron deficiency replacement, they had a significant improvement in LVEF (difference 2.51%; 95% confidence interval [CI], 1.74% to 3.29%; P<0.0001), LV systolic volume index (difference −6.68ml; 95% CI −1.91ml to −11.45ml; P=0.007) and LV GLS (difference −1.11%; CI 95%, −0.4% to −1.81%; P=0.003), with a relative benefit in LV GLS of 10.57%. Other echocardiography parameters didn't show significant differences. Conclusion In patients with stable heart failure and LVEF <50%, replacement of iron deficiency with FCM improves systolic parameters, especially left ventricular global longitudinal strain. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): Fundaciόn Fisabio (Fomento de la Investigaciόn Sanitaria y Biomédica de la Comunidad Valenciana)

Early improvement of global longitudinal strain after iron deficiency correction in heart failure with reduced ejection fraction

“…Whereas these previous studies in populations with unknown or low rate of optimal medical treatment for HFrEF noted early improvements in LVEF after iron treatment, [29][30][31] in our study we observed no significant change in LVEF but an early improved LV-GLS, thus suggesting that iron repletion leads to an incipient increase in contractility that is detected by LV-GLS before an eventual improvement of the LVEF. It is possible that the high rate of recommended treatment for HF in our patients (according to the 2016 Guidelines 20 ) would have resulted in an optimized LVEF, consequently not initially so influenceable by the effect of iron repletion.…”

“…Another study methodologically similar to ours, 31 in iron‐deficient non‐anemic patients with LVEF < 50% detected on echocardiography a significant improvement of LVEF (2.5%) and GLS (−1.1%) after 4 weeks of ferric carboxymaltose. Despite some differences with our study, such as the LVEF threshold to include patients, or the lack of data on baseline medical treatment, in both studies an improvement in GLS was detected 4 weeks after treatment.…”

“…26 A retrospective echocardiographic study found an improvement in LVEF, 29 and a post hoc analysis of the Myocardial-IRON trial 12 found a short-term improvement in LVEF in cardiac magnetic resonance after intravenous ferric carboxymaltose in patients with greater systolic dysfunction at baseline. 30 Another study methodologically similar to ours, 31 in iron-deficient non-anemic patients with LVEF < 50% detected on echocardiography a significant improvement of LVEF (2.5%) and GLS (−1.1%) after 4 weeks of ferric carboxymaltose. Despite some differences with our study, such as the LVEF threshold to include patients, or the lack of data on baseline medical treatment, in both studies an improvement in GLS was detected 4 weeks after treatment.…”