Introduction: Iron deficiency (ID) is common, in heart failure with reduced ejection fraction (HFrEF), resulting in decreased functional capacity, increased hospitalization and mortality. The European Heart Fa-ilure Guidelines recommends ID correction in HFrEF, but guidelines are unclear for iron deficiency in heart failure with mid-range ejection fraction (HFmrEF) or heart failure with preserved ejection fraction (HFpEF). Objective: ID assessment in relation to severity of heart failure (HF) assessed by NYHA functional class, left ventricular systolic function and natriuretic pepti-de level.
Methods: T he observational study evaluated patients with HF (diagnosed according to ESC recommendati-ons) relative to a control group. Exclusion criteria were the presence of other causes of ID, severe anemia and chronic iron or erythropoietic substitution therapy. ID was evaluated by seric iron (Fs) and serum ferritin (Fr). Functional iron deficiency (FID) was defined as serum Fr values of 100-299 ng / mL, and absolute iron defici-ency (AID) values of Fr <100 ng/mL. ID was analyzed according to NYHA functional class, left ventricular ejection fraction (LVEF), NTproBNP, sedimentation rate (VSH), and C-reactive protein (CRP).
Results: 43 patients with HF were included, 41.8% male, mean age 74.7±9.5 years and 27 healthy volunte-ers with comparable profile. The mean hemoglobin was similar between the two groups (13±2.1 vs. 13.2±1.6 g/ dl, p=0.1). 21% of the patients had HFrEF, 42% HFmrEF and 37% HFpEF. In patients with HF values of Fs (75.7±45 vs. 87±41 pg/dl, p=0.03) and Fr (186.5±180 vs. 194.4±80 ng/ml, p=0.03) were lower than in the control group, 81% of patients with HF had ID, of which 44% (n=19) had FID and 37% (n=16) AID. 20% of patients with ID had HFrEF, 45% HFiEF, and 34% had HFpEF. Fs-correlated positively with LVEF (r=0.3, p=0.04) and had significant variability between NYHA classes II and IV (9.9 Chi square, p=0.007). Fr decreased mar-kedly for Class III NYHA, then for class II (336.6±241.8 vs. 106.9±85.7 ng/mL, p=0.007). NTproBNP was more elevated in patients with AID than in those with FID (7175.5±7753.2 vs. 3312.8±3966.3 pg/mL, p=0.03) and was negatively correlated with Fr (r=-0.35, p=0.01) and especially Fs (r=-0.51, p=0.001). There was an inverse relationship between Fs and erythrocyte sedimentation rate (r=-0.36, p=0.01) and CRP (r=-0.46, p=0.002).
Conclusions: Iron deficiency is common in advanced heart failure, being related to markers of inflammation. The high prevalence of iron deficiency in heart failure with intermediate or preserved ejection fraction requi-res studies to validate the benefit of iron substitution therapy in these categories of patients.