Effect of intravenous iron sucrose on exercise tolerance in anemic and nonanemic patients with symptomatic chronic heart failure and iron deficiency FERRIC-HF: a randomized, controlled, observer-blinded trial

Metabolic abnormalities of the heart in type II diabetes

Type 2 diabetes mellitus escalates the risk of heart failure partly via its ability to induce a cardiomyopathic state that is independent of coronary artery disease and hypertension. Although the pathogenesis of diabetic cardiomyopathy has yet to be fully elucidated, aberrations in cardiac substrate metabolism and energetics are thought to be key drivers. These aberrations include excessive fatty acid utilisation and storage, suppressed glucose oxidation and impaired mitochondrial oxidative phosphorylation. An appreciation of how these abnormalities arise and synergise to promote adverse cardiac remodelling is critical to their effective amelioration. This review focuses on disturbances in myocardial fuel (fatty acids and glucose) flux and energetics in type 2 diabetes, how these disturbances relate to the development of diabetic cardiomyopathy and the potential therapeutic agents that could be used to correct them.

The Efficacy and Safety of Iron Supplementation in Patients With Heart Failure and Iron Deficiency: A Systematic Review and Meta-analysis

BACKGROUND

Iron deficiency (ID) is a common comorbidity in patients with heart failure (HF) and has been associated with increased mortality and hospitalizations. However, the benefit and safety of iron supplementation in treating HF and ID in randomized controlled trials (RCTs) are inconclusive. We therefore performed a meta-analysis to overcome this limitation.

METHODS

PubMed, the Cochrane Library, and ClinicalTrials.gov were systematically searched for eligible trials up to December 31, 2014. We also searched the references of all relevant studies and reviews for more trials. Only RCTs reporting the clinical impact of iron therapy in patients with HF with ID compared with no iron treatment were enrolled in our meta-analysis.

RESULTS

Five clinical trials comprising a total of 907 patients were finally included. Compared with placebo or no treatment, additional iron therapy was associated with a significantly reduced rate of hospitalization for HF (odds ratio [OR], 0.28; 95% confidence interval [CI], 0.16-0.49), though all-cause mortality was not significantly different (OR, 0.81; 95% CI, 0.42-1.57). In 4 studies where these endpoints were combined, the incidence of hospitalization for HF and death was lowered in the iron supplementation group (OR, 0.47; 95% CI, 0.29-0.76). There was no increase in the risk of adverse events.

CONCLUSIONS

Iron supplementation significantly reduced the risk of (a) hospitalization for HF and (b) the combined endpoint of hospitalization for HF and death, without increasing the risk of adverse events in patients with symptomatic systolic HF and ID. However, the current data are inadequate to make a clear determination upon mortality.

Is Correction of Iron Deficiency a New Addition to the Treatment of the Heart Failure?

Anemia is present in about 40% of heart failure (HF) patients. Iron deficiency (ID) is present in about 60% of the patients with anemia (about 24% of all HF patients) and in about 40% of patients without anemia (about 24% of all HF patients). Thus ID is present in about half the patients with HF. The ID in HF is associated with reduced iron stores in the bone marrow and the heart. ID is an independent risk factor for severity and worsening of the HF. Correction of ID with intravenous (IV) iron usually corrects both the anemia and the ID. Currently used IV iron preparations are very safe and effective in treating the ID in HF whereas little information is available on the effectiveness of oral iron. In HF IV iron correction of ID is associated with improvement in functional status, exercise capacity, quality of life and, in some studies, improvement in rate of hospitalization for HF, cardiac structure and function, and renal function. Large long-term adequately-controlled intervention studies are needed to clarify the effect of IV iron in HF. Several heart associations suggest that ID should be routinely sought for in all HF patients and corrected if present. In this paper we present our approach to diagnosis and treatment of iron deficiency in heart failure.

Iron supplementation effectively suppresses gastrocnemius muscle lesions to improve exercise capacity in chronic heart failure rats with anemia

OBJECTIVE

For patients with chronic heart failure (CHF), exertional fatigue is one of the most common and debilitating symptoms. However, the poor relationship between heart dysfunction and exercise capacity has been ascribed to peripheral abnormalities. Several previous studies confirmed that iron supplementation could significantly improve the exercise capacity of patients with CHF, although they did not analyze effects in the musculoskeletal system. The aim of this study was to investigate the effect of iron treatment on gastrocnemius muscles of CHF rats with anemia.

METHODS

Male Sprague-Dawley rats were subjected to coronary ligation to induce heart failure. At the same time, blood (1-1.5 mL) was withdrawn from the retro-orbital plexus once every week to induce anemia. After 6 wk of this process, iron dextran was administered to the CHF rats with anemia (CHFa rats) at the dose of 8, 16, 32, or 64 mg/kg every 2 d for 2 wk.

RESULTS

Iron dextran (8 mg/kg every 2 d) effectively improved hemodynamic parameters (P < 0.05) compared with CHFa rats. Similarly, this dose of iron dextran significantly reduced the ratio of heart weight to body weight (P < 0.01), whereas it significantly increased the distance run (m) to exhaustion (P < 0.01). Iron dextran effectively inhibited sarcoplasmic vacuolation and muscle atrophy of gastrocnemius muscles in CHFa rats, as evaluated by pathologic examinations. Other iron treatments, however, were found to be ineffective on the same parameters, so particular focus was placed on the iron dextran (8 mg/kg every 2 d) group in subsequent analyses. Consistently, phospho-p38 in gastrocnemius muscles of CHFa rats was markedly suppressed by iron dextran. Additionally, iron dextran significantly decreased c-fos and c-jun and up-regulated cellular FLICE-inhibitory protein expression levels.

Repletion of Iron Stores With the Use of Oral Iron Supplementation in Patients With Systolic Heart Failure

BACKGROUND

Iron deficiency is associated with reduced functional capacity and increased mortality in patients with heart failure with reduced ejection fraction (HFrEF). Correction of iron deficiency in HFrEF patients with the use of intravenous iron improves symptoms, quality of life, and exercise performance. Whether oral iron improves iron stores in HFrEF patients is unknown. We conducted a retrospective study to assess the efficacy of oral iron supplementation in iron-deficient HFrEF patients.

METHODS AND RESULTS

Iron-deficient HFrEF patients with a record of oral iron supplementation and iron studies before and ∼180 days after supplementation were identified. Iron deficiency was defined as ferritin <100 ng/mL or as ferritin 100-300 ng/mL with transferrin saturation (Tsat) <20%. Spearman correlation was performed to assess for treatment responsiveness. In 105 patients, ferritin (from median 39 ng/mL to 75 ng/mL), Tsat (from 10% to 21%), iron (from 34 μg/dL to 69 μg/dL), and hemoglobin (from 10.4 g/dL to 11.6 g/dL) values increased (P < .0001), whereas total iron-binding capacity decreased (from 343 to 313 μg/dL; P = .0007) at 164 days after initiation of oral iron supplementation.

CONCLUSIONS

In this retrospective study, oral iron supplementation improved iron stores similarly to previously reported results with the use of intravenous iron repletion in HFrEF patients, suggesting that oral iron merits prospective evaluation as an intervention strategy in HFrEF.

Effects of blood transfusion on exercise capacity in thalassemia major patients

Anemia has an important role in exercise performance. However, the direct link between rapid changes of hemoglobin and exercise performance is still unknown.To find out more on this topic, we studied 18 beta-thalassemia major patients free of relevant cardiac dysfunction (age 33.5±7.2 years,males = 10). Patients performed a maximal cardiopulmolmonary exercise test (cycloergometer, personalized ramp protocol, breath-by-breath measurements of expired gases) before and the day after blood transfusion (500 cc of red cell concentrates). After blood transfusion, hemoglobin increased from 10.5±0.8 g/dL to 12.1±1.2 (p<0.001), peak VO₂ from 1408 to 1546mL/min (p<0.05), and VO₂ at anaerobic threshold from 965 to 1024mL/min (p<0.05). No major changes were observed as regards heart and respiratory rates either at peak exercise or at anaerobic threshold. Similarly, no relevant changes were observed in ventilation efficiency, as evaluated by the ventilation vs. carbon dioxide production relationship, or in O₂ delivery to the periphery as analyzed by the VO₂ vs. workload relationship. The relationship between hemoglobin and VO₂ changes showed, for each g/dL of hemoglobin increase, a VO₂ increase = 82.5 mL/min and 35 mL/min, at peak exercise and at anaerobic threshold, respectively. In beta-thalassemia major patients, an acute albeit partial anemia correction by blood transfusion determinates a relevant increase of exercise performance, observed both at peak exercise and at anaerobic threshold.

Iron homeostasis and pulmonary hypertension: iron deficiency leads to pulmonary vascular remodeling in the rat

RATIONALE

Iron deficiency without anemia is prevalent in patients with idiopathic pulmonary arterial hypertension and associated with reduced exercise capacity and survival.

OBJECTIVES

We hypothesized that iron deficiency is involved in the pathogenesis of pulmonary hypertension and iron replacement is a possible therapeutic strategy.

METHODS AND RESULTS

Rats were fed an iron-deficient diet (IDD, 7 mg/kg) and investigated for 4 weeks. Iron deficiency was evident from depleted iron stores (decreased liver, serum iron, and ferritin), reduced erythropoiesis, and significantly decreased transferrin saturation and lung iron stores after 2 weeks IDD. IDD rats exhibited profound pulmonary vascular remodeling with prominent muscularization, medial hypertrophy, and perivascular inflammatory cell infiltration, associated with raised pulmonary artery pressure and right ventricular hypertrophy. IDD rat lungs demonstrated increased expression of hypoxia-induced factor-1α and hypoxia-induced factor-2α, nuclear factor of activated T cells and survivin, and signal transducers and activators of transcription-3 activation, which promote vascular cell proliferation and resistance to apoptosis. Biochemical examination showed reduced mitochondrial complex I activity and mitochondrial membrane hyperpolarization in mitochondria from IDD rat pulmonary arteries. Along with upregulation of the glucose transporter, glucose transporter 1, and glycolytic genes, hk1 and pdk1, lung fluorine-18-labeled 2-fluoro-2-deoxyglucose ligand uptake was significantly increased in IDD rats. The hemodynamic and pulmonary vascular remodeling were reversed by iron replacement (ferric carboxymaltose, 75 mg/kg) and attenuated in the presence of iron deficiency by dichloroacetate and imatinib, 2 putative treatments explored for pulmonary arterial hypertension that target aerobic glycolysis and proliferation, respectively.

CONCLUSIONS

These data suggest a major role for iron in pulmonary vascular homeostasis and support the clinical evaluation of iron replacement in patients with pulmonary hypertension.

Iron therapy for the treatment of iron deficiency in chronic heart failure: intravenous or oral?

This article considers the use and modality of iron therapy to treat iron deficiency in patients with heart failure, an aspect of care which has received relatively little attention compared with the wider topic of anaemia management. Iron deficiency affects up to 50% of heart failure patients, and is associated with poor quality of life, impaired exercise tolerance, and mortality independent of haematopoietic effects in this patient population. The European Society of Cardiology Guidelines for heart failure 2012 recommend a diagnostic work-up for iron deficiency in patients with suspected heart failure. Iron absorption from oral iron preparations is generally poor, with slow and often inefficient iron repletion; moreover, up to 60% of patients experience gastrointestinal side effects. These problems may be exacerbated in heart failure due to decreased gastrointestinal absorption and poor compliance due to pill burden. Evidence for clinical benefits using oral iron is lacking. I.v. iron sucrose has consistently been shown to improve exercise capacity, cardiac function, symptom severity, and quality of life. Similar findings were observed recently for i.v. ferric carboxymaltose in patients with systolic heart failure and impaired LVEF in the double-blind, placebo-controlled FAIR-HF and CONFIRM-HF trials. I.v. iron therapy may be better tolerated than oral iron, although confirmation in longer clinical trials is awaited. Routine diagnosis and management of iron deficiency in patients with symptomatic heart failure regardless of anaemia status is advisable, and, based on current evidence, prompt intervention using i.v. iron therapy should now be considered.

Cardiac ferroportin regulates cellular iron homeostasis and is important for cardiac function

Iron is essential to the cell. Both iron deficiency and overload impinge negatively on cardiac health. Thus, effective iron homeostasis is important for cardiac function. Ferroportin (FPN), the only known mammalian iron-exporting protein, plays an essential role in iron homeostasis at the systemic level. It increases systemic iron availability by releasing iron from the cells of the duodenum, spleen, and liver, the sites of iron absorption, recycling, and storage respectively. However, FPN is also found in tissues with no known role in systemic iron handling, such as the heart, where its function remains unknown. To explore this function, we generated mice with a cardiomyocyte-specific deletion of Fpn. We show that these animals have severely impaired cardiac function, with a median survival of 22 wk, despite otherwise unaltered systemic iron status. We then compared their phenotype with that of ubiquitous hepcidin knockouts, a recognized model of the iron-loading disease hemochromatosis. The phenotype of the hepcidin knockouts was far milder, with normal survival up to 12 mo, despite far greater iron loading in the hearts. Histological examination demonstrated that, although cardiac iron accumulates within the cardiomyocytes of Fpn knockouts, it accumulates predominantly in other cell types in the hepcidin knockouts. We conclude, first, that cardiomyocyte FPN is essential for intracellular iron homeostasis and, second, that the site of deposition of iron within the heart determines the severity with which it affects cardiac function. Both findings have significant implications for the assessment and treatment of cardiac complications of iron dysregulation.

The impact of intravenous ferric carboxymaltose on renal function: an analysis of the FAIR-HF study

AIMS

Anaemia and iron deficiency are constituents of the cardio-renal syndrome in chronic heart failure (CHF). We investigated the effects of i.v. iron in iron-deficient CHF patients on renal function, and the efficacy and safety of this therapy in patients with renal dysfunction.

METHODS AND RESULTS

The FAIR-HF trial randomized 459 CHF patients with iron deficiency (ferritin <100 µg/L, or between 100 and 299 µg/L if transferrin saturation was <20%): 304 to i.v. ferric carboxymaltose (FCM) and 155 to placebo, and followed-up for 24 weeks. Renal function was assessed at baseline and at weeks 4, 12, and 24, using the estimated glomerular filtration rate (eGFR, mL/min/1.73 m(2) ), calculated from the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula. At baseline, renal function was similar between groups (62.4 ± 20.6 vs. 62.9 ± 23.4 mL/min/1.73 m(2) , FCM vs. placebo). Compared with placebo, treatment with FCM was associated with an increase in eGFR [treatment effect: week 4, 2.11 ± 1.21 (P = 0.082); week 12, 2.41 ± 1.33 (P = 0.070); and week 24, 2.98 ± 1.44 mL/min/1.73 m(2) (P = 0.039)]. This effect was seen in all pre-specified subgroups (P > 0.20 for interactions). No interaction between the favourable effects of FCM and baseline renal function was seen for the primary endpoints [improvement in Patient Global Assessment (P = 0.43) and NYHA class (P = 0.37) at 24 weeks]. Safety and adverse event profiles were similar in patients with baseline eGFR <60 and ≥60 mL/min/1.73 m(2) .

CONCLUSIONS

Treatment of iron deficiency in CHF patients with i.v. FCM was associated with an improvement in renal function. FCM therapy was effective and safe in CHF patients with renal dysfunction.

Changes in Echocardiographic Parameters in Iron Deficiency Patients with Heart Failure and Chronic Kidney Disease Treated with Intravenous Iron

BACKGROUND

Treatment of iron deficiency helps to improve cardiac and renal function in patients with chronic heart failure. However, the mechanism by which this occurs is currently unclear.

METHODS

We undertook a double-blind, randomised, placebo-controlled study of intravenous iron sucrose treatment (200mg/mL weekly for five weeks) in patients with chronic heart failure, chronic kidney disease and iron-deficiency anaemia receiving optimal treatment for chronic heart failure (N=60). Markers of disease severity, iron status, anaemia and inflammation were measured during a six-month follow-up period, and evaluation of echocardiographic parameters was performed at baseline and six months after treatment.

RESULTS

At six months after treatment initiation, intravenous iron was associated with reduced severity of the symptoms of chronic heart failure and improved renal function (both p<0.001 versus control). Also, ferritin and transferrin saturation levels were increased, as were haemoglobin levels, whereas inflammatory markers were reduced (all p<0.001 versus control). Left ventricular systolic and diastolic diameters were increased and improved left ventricular function correlated with iron status in patients receiving intravenous iron but not patients in the control group.

CONCLUSIONS

Intravenous iron treatment was associated with improved myocardial functional parameters and cardiac dimensions in patients with anaemia and chronic kidney disease.

The safety of intravenous iron preparations: systematic review and meta-analysis

OBJECTIVE

To amass all available evidence regarding the safety of intravenous (IV) iron preparations to provide a true balance of efficacy and safety.

METHODS

Systematic review and meta-analysis of all randomized clinical trials comparing IV iron to another comparator. All electronic databases until January 1, 2014, were reviewed. Primary outcome was occurrence of severe adverse events (SAEs). Secondary outcomes included all-cause mortality and other adverse events (AEs). Subgroup analysis was performed on the basis of type of IV iron, comparator, treated condition, and system involved.

RESULTS

A total of 103 trials published between 1965 through 2013 were included. A total of 10,390 patients were treated with IV iron compared with 4044 patients treated with oral iron, 1329 with no iron, 3335 with placebo, and 155 with intramuscular iron. There was no increased risk of SAEs with IV iron (relative risk [RR], 1.04; 95% CI, 0.93-1.17; I(2)=9%). Subgroup analysis revealed a decreased rate of SAEs when IV iron was used to treat heart failure (RR, 0.45; 95% CI, 0.29-0.70; I(2)=0%). Severe infusion reactions were more common with IV iron (RR, 2.47; 95% CI, 1.43-4.28; I(2)=0%). There was no increased risk of infections with IV iron. Gastrointestinal AEs were reduced with IV iron.

CONCLUSION

Intravenous iron therapy is not associated with an increased risk of SAEs or infections. Infusion reactions are more pronounced with IV iron.

Iron therapy in anaemic adults without chronic kidney disease

BACKGROUND

Anaemia affects about a quarter of the world's population. An estimated 50% of anaemic people have anaemia due to iron deficiency.

OBJECTIVES

To assess the safety and efficacy of iron therapies for the treatment of adults with anaemia who are not pregnant or lactating and do not have chronic kidney disease.

SEARCH METHODS

We ran the search on 11 July 2013. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, EMBASE (Ovid SP), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) Plus (EBSCO Host), the Institute for Scientific Information Web of Science (ISI WOS) Scientific Citation Index (SCI)-EXPANDED (1970) and Conference Proceedings Citation Index (CPCI)-Science (1990) and Clinicaltrials.gov; we also screened reference lists. An updated search was run on 24 November 2014 but the results have not yet been incorporated into the review.

SELECTION CRITERIA

Two review authors independently selected references for further assessment by going through all titles and abstracts. Further selection was based on review of full-text articles for selected references.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted study data. We calculated the risk ratio (RR) with 95% confidence interval (CI) for binary outcomes and the mean difference (MD) or the standardised mean difference (SMD) with 95% CI for continuous outcomes. We performed meta-analysis when possible, when I(2) was less than or equal to 80% using a fixed-effect or random-effects model, using Review Manager software. The range of point estimates for individual studies is presented when I(2) > 80%.

MAIN RESULTS

We included in this systematic review 4745 participants who were randomly assigned in 21 trials. Trials were conducted in a wide variety of clinical settings. Most trials included participants with mild to moderate anaemia and excluded participants who were allergic to iron therapy. All trials were at high risk of bias for one or more domains. We compared both oral iron and parenteral iron versus inactive controls and compared different iron preparations.The comparison between oral iron and inactive control revealed no evidence of clinical benefit in terms of mortality (RR 1.05, 95% CI 0.68 to 1.61; four studies, N = 659; very low-quality evidence). The point estimate of the mean difference in haemoglobin levels in individual studies ranged from 0.3 to 3.1 g/dL higher in the oral iron group than in the inactive control group. The proportion of participants who required blood transfusion was lower with oral iron than with inactive control (RR 0.74, 95% CI 0.55 to 0.99; three studies, N = 546; very low-quality evidence). Evidence was inadequate for determination of the effect of parenteral iron on mortality versus oral iron (RR 1.49, 95% CI 0.56 to 3.94; 10 studies, N = 2141; very low-quality evidence) or inactive control (RR 1.04, 95% CI 0.63 to 1.69; six studies, N = 1009; very low-quality evidence). Haemoglobin levels were higher with parenteral iron than with oral iron (MD -0.50 g/dL, 95% CI -0.73 to -0.27; six studies, N = 769; very low-quality evidence). The point estimate of the mean difference in haemoglobin levels in individual studies ranged between 0.3 and 3.0 g/dL higher in the parenteral iron group than in the inactive control group. Differences in the proportion of participants requiring blood transfusion between parenteral iron and oral iron groups (RR 0.61, 95% CI 0.24 to 1.58; two studies, N = 371; very low-quality evidence) or between parenteral iron groups and inactive controls (RR 0.84, 95% CI 0.66 to 1.06; eight studies, N = 1315; very low-quality evidence) were imprecise. Average blood volume transfused was less in the parenteral iron group than in the oral iron group (MD -0.54 units, 95% CI -0.96 to -0.12; very low-quality evidence) based on one study involving 44 people. Differences between therapies in quality of life or in the proportion of participants with serious adverse events were imprecise (very low-quality evidence). No trials reported severe allergic reactions due to parenteral iron, suggesting that these are rare. Adverse effects related to oral iron treatment included nausea, diarrhoea and constipation; most were mild.Comparisons of one iron preparation over another for mortality, haemoglobin or serious adverse events were imprecise. No information was available on quality of life. Thus, little evidence was found to support the use of one preparation or regimen over another.Subgroup analyses did not reveal consistent results; therefore we were unable to determine whether iron is useful in specific clinical situations, or whether iron therapy might be useful for people who are receiving erythropoietin.

AUTHORS' CONCLUSIONS

• Very low-quality evidence suggests that oral iron might decrease the proportion of people who require blood transfusion, and no evidence indicates that it decreases mortality. Oral iron might be useful in adults who can tolerate the adverse events, which are usually mild.• Very low-quality evidence suggests that intravenous iron results in a modest increase in haemoglobin levels compared with oral iron or inactive control without clinical benefit.• No evidence can be found to show any advantage of one iron preparation or regimen over another.• Additional randomised controlled trials with low risk of bias and powered to measure clinically useful outcomes such as mortality, quality of life and blood transfusion requirements are needed.

Effects of an accelerated intravenous iron regimen in hospitalized patients with advanced heart failure and iron deficiency

STUDY OBJECTIVE

To assess the short-term efficacy and safety of an accelerated intravenous iron regimen in hospitalized patients with heart failure and iron deficiency.

DESIGN

Prospective, single-arm, open-label study.

SETTING

Large tertiary care medical center.

PATIENTS

Thirteen patients with New York Heart Association class III-IV heart failure, anemia (hemoglobin level ≤ 12.0 g/dl), and iron deficiency (ferritin level < 100 ng/ml, or ferritin level of 100-300 ng/ml with transferrin saturation < 20%) hospitalized between April 2011 and December 2013.

INTERVENTION

All patients received sodium ferric gluconate 250 mg in 100 ml of normal saline intravenously over 2 hours twice/day until the iron deficit was corrected or the patient was discharged.

MEASUREMENTS AND MAIN RESULTS

Changes in hematologic parameters were assessed at 1-4 weeks after therapy. Patients received a mean ± standard deviation (SD) total iron dose of 1269 ± 207 mg over 3.4 ± 1.0 days. After a mean ± SD follow-up of 13.1 ± 5.6 days, intravenous iron increased hemoglobin level by 1.2 g/dl (95% confidence interval [CI] 0.45-1.9, p=0.005), ferritin level by 364.2 ng/ml (95% CI 129.7-598.7, p=0.007), and transferrin saturation by 10.5% (95% CI 6.5-14.6%, p<0.001). Changes in hemoglobin level did not correlate with volume status, as determined by differences in body weight. No significant changes in blood pressure or heart rate were observed. Adverse events were few and minor in severity (e.g., nausea, constipation, and abdominal discomfort).

CONCLUSION

An accelerated intravenous iron regimen improved hematologic parameters and was well tolerated in hospitalized patients with advanced heart failure. A randomized multicenter trial comparing this regimen with placebo is warranted.

Anaemia in chronic obstructive pulmonary disease: an insight into its prevalence and pathophysiology

Chronic obstructive pulmonary disease (COPD) is a major health problem, with increasing morbidity and mortality. There is a growing literature regarding the extra-pulmonary manifestations of COPD, which can have a significant impact on symptom burden and disease progression. Anaemia is one of the more recently identified co-morbidities, with a prevalence that varies between 4.9% and 38% depending on patient characteristics and the diagnostic criteria used. Systemic inflammation seems to be an important factor for its establishment and repeated bursts of inflammatory mediators during COPD exacerbations could further inhibit erythropoiesis. However, renal impairment, malnutrition, low testosterone levels, growth hormone level abnormalities, oxygen supplementation, theophylline treatment, inhibition of angiotensin-converting enzyme and aging itself are additional factors that could be associated with the development of anaemia. The present review evaluates the published literature on the prevalence and significance of anaemia in COPD. Moreover, it attempts to elucidate the reasons for the high variability reported and investigates the complex pathophysiology underlying the development of anaemia in these patients.

Diagnosis and treatment of iron deficiency in patients with heart failure: expert position paper from French cardiologists

The prevalence of iron deficiency is high -even in the absence of anaemia- in patients with chronic heart failure (HF). Although iron deficiency is easily diagnosed with two biomarkers (serum ferritin and transferrin saturation), it is underdiagnosed in patients with HF. Iron is not only necessary for red blood cells, but also for cells in tissues with high-energy demands (heart, muscle, brain). Even before the onset of anaemia, HF patients with iron deficiency have decreased physical and cognitive performances and a poorer quality of life. Moreover, iron deficiency is a risk factor, independent of anaemia, of unfavourable outcome (death or heart transplantation) in patients with chronic HF. Several randomized controlled studies have shown improvement in exercise capacity, New York Heart Association functional class and quality of life after correction of iron deficiency. The results of these clinical trials, which are supported by European guidelines, suggest considering iron deficiency in HF as a possible therapeutic target.

New therapeutic options in heart failure. What's on the horizon? An overview

Heart failure is a complex clinical syndrome responsible for high morbidity and mortality in the world. Despite advances in the management of heart failure, the prognosis of these patients remains poor and there is a critical need for new treatment strategies improving the clinical outcomes. New approaches in heart failure therapies target cellular mechanisms, as well as mechanical and structural aspects of heart failure that are not addressed by recent therapies. These include abnormalities in molecular mechanisms, electrical conduction and ventricular remodeling. This review presents the pathophysiological basis, mechanisms of action and available clinical efficacy and safety data of drugs and mechanical therapies that are currently under development.

Cost-utility of ferric carboxymaltose (Ferinject®) for iron-deficiency anemia patients with chronic heart failure in South Korea

BACKGROUND

Iron-deficiency anemia (IDA) is prevalent in patients with advanced chronic heart failure (CHF). It affects the patients' overall physical condition and is suggested as a strong outcome predictor in CHF. Recent clinical trials suggested that intravenous iron supplementation improves CHF functional status and quality of life. The aim of this study was to assess the cost-effectiveness of ferric carboxymaltose(FCM) in CHF patients with IDA.

METHODS

Ferric carboxymaltose, an intravenous iron preparation, was compared with placebo. The target population comprised CHF patients with IDA in hospital and outpatient care settings. We conducted this study from the Korean healthcare payers' perspective with a time horizon of 24 weeks. One clinical trial provided the clinical outcomes of ferric carboxymaltose therapy. The improvement rates of the New York Heart Association (NYHA) functional class in the placebo and ferric carboxymaltose groups were used to estimate effectiveness in the base-case model. We also conducted a scenario 2 analysis using quality of life investigated in the clinical trial. A panel survey was conducted to obtain the ratio of healthcare resource use based on NYHA class in Korea. Cost-effectiveness was expressed as incremental cost (US dollars) per quality-adjusted life-year (QALY) gained.

RESULTS

In the base-case analysis, the incremental cost-effectiveness ratio (ICER) of ferric carboxymaltose compared with placebo was $22,192 (₩25,010,451) per QALY gained. The sensitivity analysis showed robust results, with the ICERs of ferric carboxymaltose ranging from $5,156 to $29,796 per QALY gained. In the scenario 2 analysis, ICER decreased to $12,598 (₩14,198,501) per QALY gained.

CONCLUSIONS

Iron repletion with ferric carboxymaltose for IDA in CHF patients was cost-effective compared with placebo.

Iron sucrose - characteristics, efficacy and regulatory aspects of an established treatment of iron deficiency and iron-deficiency anemia in a broad range of therapeutic areas

INTRODUCTION

Iron is a key element in the transport and utilization of oxygen and a variety of metabolic pathways. Iron deficiency is a major cause of anemia and can be associated with fatigue, impaired physical function and reduced quality of life. Administration of oral or intravenous (i.v.) iron is the recommended treatment for iron-deficiency anemia (IDA) in different therapeutic areas.

AREAS COVERED

This article provides an overview of studies that evaluated i.v. iron sucrose for anemia and iron status management, either alone or in combination with erythropoiesis-stimulating agents, across various diseases and conditions.

EXPERT OPINION

Iron sucrose is an established, effective and well-tolerated treatment of IDA in patients with acute or chronic conditions such as chronic kidney disease, inflammatory bowel disease, pregnancy (second and third trimester), postpartum period, heavy menstrual bleeding and cancer who need rapid iron supply and in whom oral iron preparations are ineffective or not tolerated. Available data on patient blood management warrant further studies on preoperative iron treatment. First experience with iron sucrose follow-on products raises questions about their therapeutic equivalence without comparative clinical data in newly diagnosed patients or patients on existing chronic treatment.

The role of erythropoietin stimulating agents in anemic patients with heart failure: solved and unresolved questions

Anemia is a common finding in congestive heart failure (CHF) and is associated with an increased mortality and morbidity. Several conditions can cause depression of erythroid progenitor cells: reduction of iron absorption and reuptake, decreased bone marrow activity, reduced endogenous erythropoietin production, and chronic inflammatory state. Anemia's etiology in CHF is complex and partially understood; it involves several systems including impaired hemodynamic condition, reduced kidney and bone perfusion, increased inflammatory activity, and neurohormonal overdrive. The use of erythropoiesis stimulating agents (ESAs) such as erythropoietin and its derivatives is recently debated; the last interventional trial seems to demonstrate a neutral or negative effect in the active arm with darbepoetin treatment. The current data is opposite to many single blind studies and previous meta-analysis showing an improvement in quality of life, New York Heart Association class, and exercise tolerance using ESA therapy. These contrasting data raise several concerns regarding the target of hemoglobin levels needing intervention, the exact anemia classification and categorization, and the standardization of hematocrit cutoffs. Some cardiac and systemic conditions (ie, hypertension, atrial fibrillation, prothrombotic status) may predispose to adverse events, and ESA administration should be avoided. To prevent the negative effects, high-dosage and chronic administration should be avoided. Clarification of these items could probably identify patients that may benefit from additional iron or ESA treatment. In this review, we discuss the interventional trials made in anemic heart failure patients, the underlying mechanism of anemia in CHF, and the potential role of ESA in this setting.

High prevalence of iron deficiency in patients with acute decompensated heart failure

AIMS

Limited data are available on iron parameters in patients hospitalized for decompensation of chronic heart failure.

METHODS AND RESULTS

Iron parameters of patients hospitalized for decompensation of chronic heart failure were prospectively assessed during the 72 h after hospital admission. Iron deficiency was defined according to the 2012 European Society of Cardiology Guidelines. Overall, 411 men (75 ± 12  years; 75% NYHA functional classes III/IV) and 421 women (81 ± 11 years; 71% NYHA classes III/IV) were evaluated. The prevalence of iron deficiency was 69% in men and 75% in women (including 41% and 49% with absolute iron deficiency, respectively). The prevalence of anaemia in men (<13 g/dL) was 68% and in women (<12 g/dL) it was 52%. Among non-anaemic patients, the prevalence of iron deficiency was 57% in men and 79% in women. Only 9% of patients received iron supplementation at the time of admission (oral, 9%; intravenous, 0.2%). Multivariate analysis showed that anaemia and antiplatelet treatment in men, and diabetes and low C-reactive protein in women, were independently associated with iron deficiency.

CONCLUSIONS

Iron deficiency is very common in patients admitted for acute decompensated heart failure, even among non-anaemic patients. Given the benefit of iron therapy in chronic heart failure, our results emphasize the need to assess iron status not only in chronic heart failure patients, but even more so in those admitted for worsening heart failure, regardless of gender, heart failure severity, or haemoglobin level. Initiating iron therapy in hospitalized heart failure patients needs to be investigated.

Effect of iron and zinc supplementation and its discontinuation on lipid profile in rats

The aim of this research was to investigate whether combined iron/zinc supplementation is more beneficial than iron supplementation alone from the perspective of the lipid profile in rats. The study was conducted on 6-week male Wistar rats in 3 stages: (1) 4-week adaptation to the diets: C (AIN-93M) and D (mineral mix without iron); (2) 4-week supplementation: 10-times more iron or iron and zinc compared to C; (3) 2-week post-supplementation period (the same diets as in the first stage). The iron and zinc content in serum was measured using ASA. Total cholesterol (TC), HDL cholesterol (HDL-C), non-HDL cholesterol (non-HDL-C) and triglycerides (TG) were determined. After 4-week supplementation (stage II) and post-supplementation (stage III) periods combined iron/zinc supplementation decreased HDL-C and increased non-HDL-C concentrations in control rats, and in contrast to iron supplementation alone TG concentration decreased. After stage II combined iron/zinc supplementation did not result in increased non-HDL-C and TG concentrations in iron deficient rats in contrast to iron supplementation alone. After stage III both iron and simultaneous iron/zinc supplementation were the cause of TC increase which was the result of the increase of non-HDL-C but not HDL-C concentration in iron deficient rats. In conclusion, there were no beneficial effects of simultaneous iron and zinc supplementation on the lipid profile of rats fed control and iron deficient diets. Combined iron and zinc supplementation may contribute to lower HDL-C and higher non-HDL-C concentrations.

Iron deficiency defined as depleted iron stores accompanied by unmet cellular iron requirements identifies patients at the highest risk of death after an episode of acute heart failure

AIM

Acute heart failure (AHF) critically deranges haemodynamic and metabolic homoeostasis. Iron is a key micronutrient for homoeostasis maintenance. We hypothesized that iron deficiency (ID) defined as depleted iron stores accompanied by unmet cellular iron requirements would in this setting predict the poor outcome.

METHODS AND RESULTS

Among 165 AHF patients (age 65 ± 12 years, 81% men, 31% de novo HF), for ID diagnosis we prospectively applied: low serum hepcidin reflecting depleted iron stores (<14.5 ng/mL, the 5th percentile in healthy peers), and high-serum soluble transferrin receptor (sTfR) reflecting unmet cellular iron requirements (≥1.59 mg/L, the 95th percentile in healthy peers). Concomitance of low hepcidin and high sTfR (the most profound ID) was found in 37%, isolated either high sTfR or low hepcidin was found in 29 and 9% of patients, and 25% of subjects demonstrated preserved iron status. Patients with low hepcidin and high sTfR had peripheral oedema, high NT-proBNP, high uric acid, low haemoglobin (P < 0.05), and 5% in-hospital mortality (0% in remaining patients). During the 12-month follow-up, 33 (20%) patients died. Those with low hepcidin and high sTfR had the highest 12-month mortality [(41% (95% CI: 29-53%)] when compared with those with isolated high sTfR [15% (5-25%)], isolated low hepcidin [7% (0-19%)] and preserved iron status (0%) (P < 0.001). Analogous mortality patterns were seen separately in anaemics and non-anaemics.

CONCLUSION

Iron deficiency defined as depleted body iron stores and unmet cellular iron requirements is common in AHF, and identifies those with the poor outcome. Its correction may be an attractive therapeutic approach.

Iron deficiency status irrespective of anemia: a predictor of unfavorable outcome in chronic heart failure patients

OBJECTIVE

To assess the prognostic significance of iron deficiency (ID) in a chronic heart failure (CHF) outpatient population.

METHODS AND RESULTS

We prospectively evaluated 127 patients with stable CHF and left ventricular ejection fraction ≤45%. Clinical and analytical data as well as information regarding the occurrence of the composite endpoint of overall mortality and nonfatal cardiovascular events were assessed. Among the 127 patients enrolled [81% men, median age: 62 years (25th-75th percentile: 53-68)], 46 (36%) patients had ID. Women, patients with higher plasma brain natriuretic peptide levels (>400 pg/ml) and with right ventricular systolic dysfunction presented ID more frequently (p < 0.05 for all). At 225 ± 139 days of follow-up, the composite endpoint occurred in 15 (12%) patients. It was more frequent in ID (24 vs. 5%, p = 0.001) and anemic patients (25 vs. 8%, p = 0.014). In a Cox regression analysis, ID was associated with a higher likelihood of composite endpoint occurrence (HR 5.00, 95% CI 1.59-15.78, p = 0.006). In a multivariable analysis adjusted for clinical variables, including the presence of anemia, ID remained a significant predictor of the composite endpoint (HR 5.38, 95% CI 1.54-18.87, p = 0.009).

CONCLUSION

In a CHF outpatient population, ID carried a higher risk of unfavorable outcome, irrespectively of the presence of anemia.

Adaptive servo-ventilation therapy improves long-term prognosis in heart failure patients with anemia and sleep-disordered breathing

Sleep disordered breathing (SDB) and anemia influences the progression of chronic heart failure (CHF). Adaptive servo-ventilation (ASV) is an effective therapeutic device for treatment of CHF, however, the impacts of ASV on CHF patients with or without anemia remain unclear.A total of 139 patients with CHF and SDB were divided into two groups: those treated with ASV (n = 53) and without ASV (n = 86). All patients were prospectively followed after discharge with the endpoints of cardiac death or progressive heart failure requiring rehospitalization. There were 65 patients (47%) with anemia among all subjects. The apnea hypopnea index was improved, and plasma BNP and high sensitive C-reactive protein levels were decreased in both groups with and without anemia by ASV therapy. The Kaplan-Meier survival curve demonstrated that the cardiac event-free rate in patients with ASV was significantly higher than in those without ASV in the anemia group (P = 0.008). However, in the non-anemia group, the cardiac event-free rate was similarly high in patients both with and without ASV (P = 0.664). Multivariate Cox proportional hazard analysis demonstrated that ASV use was an independent predictor of cardiac events in the anemia group (P = 0.0308), but not in the non-anemia group.ASV treatment for CHF and SDB has more favorable impacts in patients with anemia than in those without anemia.

Contemporary strategies in the diagnosis and management of heart failure

Heart failure (HF) is an important public health problem, and strategies are needed to improve outcomes and decrease health care resource utilization and costs. Its prevalence has increased as the population ages, and HF continues to be associated with a high mortality rate and frequent need for hospitalization. The total cost of care for patients with HF was $30.7 billion in 2012, and it is estimated to more than double to $69.8 billion by 2030. Given this reality, there has been recent investigation into ways of identifying and preventing HF in patients at risk (stage A HF) and those with cardiac structural and functional abnormalities but no clinical HF symptoms (stage B). For patients who have symptoms of HF (stage C), there has been important research into the most effective ways to decongest patients hospitalized with acute decompensated HF and prevent future hospital readmissions. Successful strategies to treat patients with HF and preserved ejection fraction, which has increased in prevalence, continue to be sought. We are in the midst of a rapid evolution in our ability to care for patients with end-stage HF (stage D) because of the introduction of and improvements in mechanical circulatory support. Left ventricular assist devices used as destination therapy offer an important therapeutic option to patients who do not qualify for heart transplant because of advanced age or excessive comorbidity. This review provides a thorough update on contemporary strategies in the diagnosis and management of HF by stage (A to D) that have emerged during the past several years.

Iron deficiency and health-related quality of life in chronic heart failure: results from a multicenter European study

Patients affected by chronic heart failure (CHF) present significant impairment of health-related quality of life (HRQoL). Iron deficiency (ID) is a common comorbidity in CHF with negative impact in prognosis and functional capacity. The role of iron in energy metabolism could be the link between ID and HRQoL. There is little information about the role of ID on HRQoL in patients with CHF. We evaluate the impact of ID on HRQoL and the interaction with the anaemia status, iron status, clinical baseline information and HRQoL, measured with the Minnesota Living with Heart Failure questionnaire (MLHFQ) was obtained at baseline in an international cohort of 1278 patients with CHF. Baseline characteristics were median age 68 ± 12, 882 (69%) were males, ejection fraction was 38% ± 15 and NYHA class was I/II/III/IV (156/247/487/66). ID (defined as ferritin level< 100 µg/L or serum ferritin 100-299 µg/L in combination with a TSAT<20%) was present in 741 patients (58%). 449 (35%) patients were anaemic. Unadjusted global scores of MLHFQ (where higher scores reflect worse HRQoL) were worse in ID and anaemic patients (ID+: 42 ± 25 vs. ID-: 37 ± 25; p-value=0.001 and A+: 46 ± 25 vs. A-: 37 ± 25; p-value<0.001). The combined influence of ID and anaemia was explored with different multivariable regression models, showing that ID but not anaemia was associated with impaired HRQoL. ID has a negative impact on HRQoL in CHF patients, and this is independent of the presence of anaemia.

The additive burden of iron deficiency in the cardiorenal-anaemia axis: scope of a problem and its consequences

AIMS

Iron deficiency (ID), anaemia, and chronic kidney disease (CKD) are common co-morbidities in chronic heart failure (CHF) and all independent predictors of unfavourable outcome. The combination of anaemia and CKD in CHF has been described as the cardiorenal-anaemia syndrome. However, the role of ID within this complex interplay of co-existing pathologies is unclear.

METHODS AND RESULTS

We studied the clinical correlates of ID (defined as ferritin <100 µg/L or 100-299 µg/L in combination with a transferrin saturation <20%, anaemia) and renal dysfunction (defined as estimated glomerular filtration rate <60 mL/min/1.73 m(2) ) and their prognostic implications in an international pooled cohort, comprising 1506 patients with CHF. Mean age was 64 ± 13 years, 74.2% were male, and 47.3% were in NYHA functional class III. The presence of ID, anaemia, CKD, or a combination of these co-morbidities was observed in 69.3% of the patients. During a median (Q1-Q3) follow-up of 1.92 years (1.18-3.26 years), 440 patients (29.2%) died. Eight-year survival rates decreased significantly from 58.0% for no co-morbidities to 44.6, 33.0, and 18.4%, for one, two, or three co-morbidities, respectively (P < 0.001). Multivariate hazard models revealed ID to be the key determinant of prognosis, either individually (P = 0.04) or in combination with either anaemia (P = 0.006), CKD (P = 0.03), or both (P = 0.02).

CONCLUSIONS

Iron deficiency frequently overlaps with anaemia and/or CKD in CHF. The presence of ID amplifies mortality risk, either alone or in combination with anaemia, CKD, or both, making it a potential viable therapeutic target.

Iron deficiency anemia in heart failure

Anemia and iron deficiency are quite prevalent in patients with heart failure (HF) and may overlap. Both anemia and iron deficiency are associated with worse symptoms and adverse clinical outcomes. In the past few years, there has been an enormous interest in the subject of iron deficiency and its management in patients with HF. In this review, the etiology and relevance of iron deficiency, iron metabolism in the setting of HF, studies on iron supplementation in patients with HF and potential cardiovascular effects of subclinical iron overload are discussed.

Erythropoiesis stimulating agents (ESAs) for congestive heart failure: the red and the black

CHF is a disease of high incidence and prevalence in the elderly. Anemia is associated with an increased mortality in these patients. Erythropoietin secretion is reduced in these patients due to complexed mechanisms. Although some improvement in quality of life has been shown when using ESAs it has not been found any decrement on mortality. Moreover, safety reports suggest an increased risk of thromboembolic event. Together with the high drug cost, the use of ESAs cannot be recommended for the treatment of CHF patients.

Iron status and survival in diabetic patients with coronary artery disease

OBJECTIVE

To investigate the impact of iron status on survival in patients with type 2 diabetes and coronary artery disease (CAD).

RESEARCH DESIGN AND METHODS

Serum ferritin, transferrin saturation (Tsat), and soluble transferrin receptor (sTfR) were measured in 287 patients with type 2 diabetes and stable CAD (65 ± 9 years of age, 78% men).

RESULTS

During a mean follow-up of 45 ± 19 months, there were 59 (21%) deaths and 60 (21%) cardiovascular hospitalizations. Both serum ferritin and sTfR strongly predicted 5-year all-cause mortality rates, independently of other variables (including hemoglobin, measures of renal function, inflammation, and neurohormonal activation). There was an exponential relationship between sTfR and mortality (adjusted hazard ratio [HR] per 1 log mg/L: 4.24 [95% CI 1.43-12.58], P = 0.01), whereas the relationship between ferritin and mortality was U-shaped (for the lowest and the highest quintiles vs. the middle quintile [reference group], respectively: adjusted HR 7.18 [95% CI 2.03-25.46], P = 0.002, and adjusted HR 5.12 [1.48-17.73], P = 0.01). Similar patterns were observed for the composite outcome of all-cause mortality or cardiovascular hospitalization, and in these multivariable models, low Tsat was related to unfavorable outcome.

CONCLUSIONS

Both low and high serum ferritin (possibly reflecting depleted and excessive iron stores, respectively) along with high serum sTfR (reflecting reduced metabolically available iron) identify patients with type 2 diabetes and CAD who have a poor prognosis.

The FIND-CKD study--a randomized controlled trial of intravenous iron versus oral iron in non-dialysis chronic kidney disease patients: background and rationale

Background

Rigorous data are sparse concerning the optimal route of administration and dosing strategy for iron therapy with or without concomitant erythropoiesis-stimulating agent (ESA) therapy for the management of iron deficiency anaemia in patients with non-dialysis dependent chronic kidney disease (ND-CKD).

Methods

FIND-CKD was a 56-week, open-label, multicentre, prospective, randomized three-arm study (NCT00994318) of 626 patients with ND-CKD and iron deficiency anaemia randomized to (i) intravenous (IV) ferric carboxymaltose (FCM) at an initial dose of 1000 mg iron with subsequent dosing as necessary to target a serum ferritin level of 400–600 µg/L (ii) IV FCM at an initial dose of 200 mg with subsequent dosing as necessary to target serum ferritin 100–200 µg/L or (iii) oral ferrous sulphate 200 mg iron/day. The primary end point was time to initiation of other anaemia management (ESA therapy, iron therapy other than study drug or blood transfusion) or a haemoglobin (Hb) trigger (two consecutive Hb values <10 g/dL without an increase of ≥0.5 g/dL).

Results

The background, rationale and study design of the trial are presented here. The study has been completed and results are expected in late 2013.

Discussion

FIND-CKD was the longest randomized trial of IV iron therapy to date. Its findings will address several unanswered questions regarding iron therapy to treat iron deficiency anaemia in patients with ND-CKD. It was also the first randomized trial to utilize both a high and low serum ferritin target range to adjust IV iron dosing, and the first not to employ Hb response as its primary end point.

The effect of iron and zinc supplementation and discontinuation of this practice on iron and zinc level in tissues in rats fed deficient diets

The effect of iron and iron/zinc supplementation on their levels in tissues of rats fed initially one of the three following regimen: C - control AIN-93 diet, D - iron deficient diet and R - diet with 50% reduction of all vitamins and minerals was investigated. The study was conducted on 6-week male Wistar rats, in 3 stages: (1) 4-week adaptation to the diets (C, D or R); (2) 4-week supplementation with the same regimen enriched with 10-times more iron (CSFe, DSFe, RSFe) or iron/zinc (CSFeZn, DSFeZn, RSFeZn); (3) 2-week post-supplementation period (the same diets as the stage I). Iron and zinc content in serum, the initial segment of intestine, liver and kidney were measured using FAAS method. After supplementation period (stage II) the content of iron in the intestine, liver and kidney in groups of rats fed DSFe and DSFeZn-diet were significantly higher (all p-values≤0.05) than in rats fed D-diet (intestine: DSFe=50.1±9.0 μg/g wet weight, DSFeZn=43.0±9.9 μg/g vs. D=16.5±2.1 μg/g; liver: DSFe=149±30 μg/g, DSFeZn=152±25 μg/g vs. D=56±13 μg/g; kidney: DSFe=74.0±8.1 μg/g, DSFeZn=72.7±6.6 μg/g vs. D=59.3±9.5 μg/g). The same significant associations (all p-values≤0.05) were observed in R rats in the intestine and liver (intestine: RSFe=60.8±6.6 μg/g, RSFeZn=54.8±6.6 μg/g vs. R=31.5±8.2 μg/g; liver: RSFe=161±10 μg/g, RSFeZn=166±21 μg/g vs. R=136±24μg/g). After post-supplementation period the statistically significant differences between supplemented and non-supplemented rats fed D- and R-diets were still observed. There was not found the effect of applied treatments on zinc status. In conclusion, iron or iron/zinc supplementation increased similarly iron level in tissues of rats fed D-diet or R-diet with prolonged effect after supplementation discontinuation.

Iron deficiency in heart failure: a practical guide

Iron is an element necessary for cells due to its capacity of transporting oxygen and electrons. One of the important co-morbidities in heart failure is iron deficiency. Iron has relevant biological functions, for example, the formation of haemoglobin, myoglobin and numerous enzymatic groups. The prevalence of iron deficiency increases with the severity of heart failure. For a long time, the influence of iron deficiency was underestimated especially in terms of worsening of cardiovascular diseases and of developing anaemia. In recent years, studies with intravenous iron agents in patients with iron deficiency and cardiovascular diseases indicated new insights in the improvement of therapy. Experimental studies support the understanding of iron metabolism. Many physicians remain doubtful of the use of intravenous iron due to reports of side effects. The aim of this review is to describe iron metabolism in humans, to highlight the influence of iron deficiency on the course and symptoms of heart failure, discuss diagnostic tools of iron deficiency and provide guidance on the use of intravenous iron.