Changes in echocardiographic and analytical parameters after iron replacement in stable heart failure patients. FER-STRAIN study

Iron deficiency replacement with intravenous ferric carboxymaltose (FCM) has demonstrated to improve clinical and prognostic parameters in patients with heart failure with reduced left ventricular ejection fraction (HFrEF). Improvement of myocardial contractility is proposed as possible hypothesis and strain 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.

Evaluate the effect of iron deficiency replacement with FCM in the strain of both ventricles in patients with stable HFrEF.

We performed an observational, analytical, longitudinal and prospective study that included 73 patients with stable HFrEF who presented iron deficiency without anemia defined as serum ferritin <100 ug/L or between 100 and 300 ug/L if the transferrin saturation was <20%. They were randomized 2:1 to iron replacement with FCM or control group. A central core lab, blinded to the treatment/control groups performed 3D echocardiograms and strain analysis. Analytical parameters and biomarkers were determined basal and four weeks after the randomization.

Mean age of the study population was 70 years old, 77% were male, 75% had high blood pressure, 70% dyslipidemia and 41% diabetes. Of the total, 51 patients were assigned to the replacement group and 22 patients to the control group. Mean left ventricular ejection fraction (LVEF) was 33%, without basal differences between both groups. Four weeks after the randomization, a significant improvement of LVEF of 2.47±2.32% (p=0.018) was observed in the replacement group, as well as in the left ventricle global longitudinal strain (LV-GLS) of -0.96±2.08% (p=0.006). In blood tests, a significant improvement of ferritin (130.9±111.98mg/L, p<0.000), hemoglobin (0.3±0.7g/dL, p=0.027) and medium corpuscular volume (1.7±2.16fL, p=0.005), and also an increase of the biomarker myeloperoxidase (40.16±138.36pmol/L, p=0.02) were detected in the treatment group. Nevertheless, these changes were not observed in the control group.

In patients with stable HFrEF replacement of iron deficiency with FCM is associated with an improvement of myocardial contractility, of LVEF measured by 3D and LV-GLS.

Variation of parameters