Estado del hierro en la insuficiencia cardiaca crónica: impacto en síntomas, clase funcional y capacidad de ejercicio submáxima

Soluble Transferrin Receptor as Iron Deficiency Biomarker: Impact on Exercise Capacity in Heart Failure Patients

The soluble transferrin receptor (sTfR) is a marker of tissue iron status, which could indicate an increased iron demand at the tissue level. The impact of sTfR levels on functional capacity and quality of life (QoL) in non-anemic heart failure (HF) patients with otherwise normal systemic iron status has not been evaluated. We conducted an observational, prospective, cohort study of 1236 patients with chronic HF. We selected patients with normal hemoglobin levels and normal systemic iron status. Tissue iron deficiency (ID) was defined as levels of sTfR > 75th percentile (1.63 mg per L). The primary endpoints were the distance walked in the 6 min walking test (6MWT) and the overall summary score (OSS) of the Minnesota Living with Heart Failure Questionnaire (MLHFQ). The final study cohort consisted of 215 patients. Overall QoL was significantly worse (51 ± 27 vs. 39 ± 20, p-value = 0.006, respectively), and the 6 MWT distance was significantly worse in patients with tissue ID when compared to patients without tissue ID (206 ± 179 m vs. 314 ± 155, p-value < 0.0001, respectively). Higher sTfR levels, indicating increased iron demand, were associated with a shorter distance in the 6 MWT (standardized β = -0.249, p < 0.001) and a higher MLHFQ OSS (standardized β = 0.183, p-value = 0.008). In this study, we show that in patients with normal systemic iron parameters, higher levels of sTfR are strongly associated with an impaired submaximal exercise capacity and with worse QoL.

Heart Failure with Preserved Ejection Fraction: a Pharmacotherapeutic Update

While guidelines for management of heart failure with reduced ejection fraction (HFrEF) are consensual and have led to improved survival, treatment options for heart failure with preserved ejection fraction (HFpEF) remain limited and aim primarily for symptom relief and improvement of quality of life. Due to the shortage of therapeutic options, several drugs have been investigated in multiple clinical trials. The majority of these trials have reported disappointing results and have suggested that HFpEF might not be as simply described by ejection fraction as previously though. In fact, HFpEF is a complex clinical syndrome with various comorbidities and overlapping distinct phenotypes that could benefit from personalized therapeutic approaches. This review summarizes the results from the most recent phase III clinical trials for HFpEF and the most promising drugs arising from phase II trials as well as the various challenges that are currently holding back the development of new pharmacotherapeutic options for these patients.

Preoperative Evaluation and Care of Heart Transplant Candidates

Heart transplantation is recommended for patients with advanced heart failure refractory to medical and device therapy, and who do not have absolute contraindications. When patients become eligible for heart transplantation, they undergo comprehensive evaluation and preparation to optimize their posttransplantation outcomes. This review provides an overview of the processes that are employed to enable the candidates to be transplant-ready when donor hearts are available.

Iron deficiency in patients of heart failure with reduced ejection fraction

Background

Heart Failure with reduced Ejection Fraction (HFrEF) is a common disorder affecting a large population. Iron deficiency (ID) with and without anaemia is an important variable which is often underreported and under treated in clinical practice, which contributes to patient symptoms. The present study was undertaken to study the prevalence and Spectrum of Iron Deficiency in patients of HFrEF.

Methods

This is a single-centre observational study. All patients with a clinical diagnosis of HFrEF presenting to the hospital were studied. Ejection Fraction (EF) was assessed on Echo and ID was diagnosed on basis of serum ferritin <100 micro g/dl or serum ferritin 100-300 micro g/dl with low Transferrin Saturation (TSAT) (< 20%).

Results

We have studied a total of 204 patients with a predominantly male population (73%) and a mean age of 62.88 years. Most of our patients were in mid-level functional class (mean 2.48 ± 0.50) and had low EF (mean 29.56 ± 6.52). Out of 204 patients, 88.7% patients had ID with 83% patients having absolute ID. Of the total patients with HF, 70% had anaemia. Amongst those with anaemia 93% had ID, and even without anaemia, 68% had absolute or functional ID, underlying the importance of evaluating iron status in all patients of HF irrespective of their haemoglobin levels.

Conclusion

This study highlights the burden of iron deficiency in heart failure patients in the Indian population and opens the way for large scale studies for better characterization of iron deficiency as well as therapeutic trials in the management of heart failure patients.

Iron Depletion in Systemic and Muscle Compartments Defines a Specific Phenotype of Severe COPD in Female and Male Patients: Implications in Exercise Tolerance

We hypothesized that iron content and regulatory factors, which may be involved in exercise tolerance, are differentially expressed in systemic and muscle compartments in iron deficient severe chronic obstructive pulmonary disease (COPD) patients. In the vastus lateralis and blood of severe COPD patients with/without iron depletion, iron content and regulators, exercise capacity, and muscle function were evaluated in 40 severe COPD patients: non-iron deficiency (NID) and iron deficiency (ID) (20 patients/group). In ID compared to NID patients, exercise capacity, muscle iron and ferritin content, serum transferrin saturation, hepcidin-25, and hemojuvelin decreased, while serum transferrin and soluble transferrin receptor and muscle IRP-1 and IRP-2 increased. Among all COPD, a significant positive correlation was detected between FEV₁ and serum transferrin saturation. In ID patients, significant positive correlations were detected between serum ferritin, hepcidin, and muscle iron content and exercise tolerance and between muscle IRP-2 and serum ferritin and hepcidin levels. In ID severe COPD patients, iron content and its regulators are differentially expressed. A potential crosstalk between systemic and muscle compartments was observed in the ID patients. Lung function and exercise capacity were associated with several markers of iron metabolism regulation. Iron status should be included in the overall assessment of COPD patients given its implications in their exercise performance.

Practical Guidance for Diagnosing and Treating Iron Deficiency in Patients with Heart Failure: Why, Who and How?

Iron deficiency (ID) is a comorbid condition frequently seen in patients with heart failure (HF). Iron has an important role in the transport of oxygen, and is also essential for skeletal and cardiac muscle, which depend on iron for oxygen storage and cellular energy production. Thus, ID per se, even without anaemia, can be harmful. In patients with HF, ID is associated with a poorer quality of life (QoL) and exercise capacity, and a higher risk of hospitalisations and mortality, even in the absence of anaemia. Despite its negative clinical consequences, ID remains under-recognised. However, it is easily diagnosed and managed, and the recently revised 2021 European Society of Cardiology (ESC) guidelines on HF provide specific recommendations for its diagnosis and treatment. Prospective randomised controlled trials in patients with symptomatic HF with reduced ejection fraction (HFrEF) show that correction of ID using intravenous iron (principally ferric carboxymaltose [FCM]) provides improvements in symptoms of HF, exercise capacity and QoL, and a recent trial demonstrated that FCM therapy following hospitalisation due to acute decompensated HF reduced the risk of subsequent HF hospitalisations. This review provides a summary of the epidemiology and pathophysiology of ID in HFrEF, and practical guidance on screening, diagnosing, and treating ID.

Deficiência de Ferro na Insuficiência Cardíaca com Fração de Ejeção Reduzida: Fisiopatologia, Diagnóstico e Tratamento

A deficiência de ferro (DF) ou ferropenia é uma importante comorbidade na insuficiência cardíaca com fração de ejeção reduzida (ICFER) estável, e muito prevalente tanto nos anêmicos como não anêmicos. A ferropenia na ICFER deve ser pesquisada por meio da coleta de saturação de transferrina e ferritina. Há dois tipos de ferropenia na IC: absoluta, em que as reservas de ferro estão depletadas; e funcional, onde o suprimento de ferro é inadequado apesar das reservas normais. A ferropenia está associada com pior classe funcional e maior risco de morte em pacientes com ICFER, e evidências científicas apontam melhora de sintomas e de qualidade de vida desses pacientes com tratamento com ferro parenteral na forma de carboximaltose férrica. O ferro exerce funções imprescindíveis como o transporte (hemoglobina) e armazenamento (mioglobina) de oxigênio, além de ser fundamental para o funcionamento das mitocôndrias, constituídas de proteínas à base de ferro, e local de geração de energia na cadeia respiratória pelo metabolismo oxidativo. A geração insuficiente e utilização anormal de ferro nas células musculares esquelética e cardíaca contribuem para a fisiopatologia da IC. A presente revisão tem o objetivo de aprofundar o conhecimento a respeito da fisiopatologia da ferropenia na ICFER, abordar as ferramentas disponíveis para o diagnóstico e discutir sobre a evidência científica existente de reposição de ferro.

Dynamic personalized risk prediction in chronic heart failure patients: a longitudinal, clinical investigation of 92 biomarkers (Bio-SHiFT study)

The aim of our observational study was to derive a small set out of 92 repeatedly measured biomarkers with optimal predictive capacity for adverse clinical events in heart failure, which could be used for dynamic, individual risk assessment in clinical practice. In 250 chronic HFrEF (CHF) patients, we collected trimonthly blood samples during a median of 2.2 years. We selected 537 samples for repeated measurement of 92 biomarkers with the Cardiovascular Panel III (Olink Proteomics AB). We applied Least Absolute Shrinkage and Selection Operator (LASSO) penalization to select the optimal set of predictors of the primary endpoint (PE). The association between repeatedly measured levels of selected biomarkers and the PE was evaluated by multivariable joint models (mvJM) with stratified fivefold cross validation of the area under the curve (cvAUC). The PE occurred in 66(27%) patients. The optimal set of biomarkers selected by LASSO included 9 proteins: NT-proBNP, ST2, vWF, FABP4, IGFBP-1, PAI-1, PON-3, transferrin receptor protein-1, and chitotriosidase-1, that yielded a cvAUC of 0.88, outperforming the discriminative ability of models consisting of standard biomarkers (NT-proBNP, hs-TnT, eGFR clinically adjusted) − 0.82 and performing equally well as an extended literature-based set of acknowledged biomarkers (NT-proBNP, hs-TnT, hs-CRP, GDF-15, ST2, PAI-1, Galectin 3) − 0.88. Nine out of 92 serially measured circulating proteins provided a multivariable model for adverse clinical events in CHF patients with high discriminative ability. These proteins reflect wall stress, remodelling, endothelial dysfunction, iron deficiency, haemostasis/fibrinolysis and innate immunity activation. A panel containing these proteins could contribute to dynamic, personalized risk assessment.

Clinical Trial Registration: 10/05/2013 https://clinicaltrials.gov/ct2/show/NCT01851538?term=nCT01851538&draw=2&rank=1.

Iron deficiency in heart failure patients: the French CARENFER prospective study

Aims

Iron deficiency (ID) is reported as one of the main co‐morbidities in patients with chronic heart failure (CHF), which then influences quality of life and prognosis. The CARENFER study aimed to assess the prevalence of ID in a large panel of heart failure (HF) patients at different stages of the disease.

Methods and results

This prospective cross‐sectional nationwide study was conducted in 48 medical units in France in 2019. Serum ferritin concentration and transferrin saturation (TSAT) index were determined in all eligible patients with a diagnosis of HF. ID diagnosis was based on the European Society of Cardiology (ESC) 2016 guidelines. Patients were classified as having either a decompensated HF or a CHF. Left ventricular ejection fraction (LVEF) was categorized as preserved (≥50%), mildly reduced (40–49%), or reduced (<40%). ID diagnosis was determined in 1661 patients, of whom 1475 could be classified as having a decompensated HF or a CHF. Patients' median age was 78 years. Decompensated HF represented 60.1% of cases. The overall prevalence of ID was 49.6% (47.1–52.1). In CHF and decompensated HF patients, respectively, ID prevalence was 39.0% (35.1–43.1) and 58.1% (54.7–61.4), P < 0.001; TSAT < 20% was respectively reported in 34.7% and 70.0% of patients (P < 0.001). Patients with preserved LVEF were more likely to have an ID (57.5%) compared with patients with mildly reduced (47.4%) or reduced LVEF (44.3%) (P < 0.001).

Conclusions

Iron deficiency was highly prevalent in patients with decompensated HF or CHF with preserved LVEF. ID prevalence defined by TSAT was higher than by the ESC criteria in decompensated HF patients, questioning the importance of ID definition to assess its prevalence.

The Impact of Clinical, Biochemical, and Echocardiographic Parameters on the Quality of Life in Patients with Heart Failure with Reduced Ejection Fraction

Despite significant advances in HF diagnosis and treatment over the recent decades, patients still characterize poor long-term prognosis with many recurrent hospitalizations and reduced health-related quality of life (HRQoL). We aimed to check the potential relationship between clinical, biochemical, or echocardiographic parameters and HRQoL in patients with HF with reduced ejection fraction (HFrEF). We included 152 adult patients hospitalized due to chronic HFrEF. We used the WHOQoL-BREF questionnaire to assess HRQoL and GNRI to evaluate nutritional status. We also analyzed several biochemical parameters and left ventricle ejection fraction. Forty (26.3%) patients were hospitalized due to HF exacerbation and 112 (73.7%) due to planned HF evaluation. The median age was 57 (48–62) years. Patients with low somatic HRQoL score had lower transferrin saturation (23.7 ± 11.1 vs. 29.7 ± 12.5%; p = 0.01), LDL (2.40 (1.80–2.92) vs. 2.99 (2.38–3.60) mmol/L; p = 0.001), triglycerides (1.18 (0.91–1.57) vs. 1.48 (1.27–2.13) mmol/L; p = 0.006) and LVEF (20 (15–25) vs. 25 (20–30)%; p = 0.003). TIBC (64.9 (58.5–68.2) vs. 57.7 (52.7–68.6); p = 0.02) was significantly higher in this group. We observed no associations between HRQoL and age or gender. The somatic domain of WHOQoL-BREF in patients with HFrEF correlated with the clinical status as well as biochemical and echocardiographic parameters. Assessment of HRQoL in HFrEF seems important in everyday practice and can identify patients requiring a special intervention

Blood Differential Gene Expression in Patients with Chronic Heart Failure and Systemic Iron Deficiency: Pathways Involved in Pathophysiology and Impact on Clinical Outcomes

Background: Iron deficiency is a common disorder in patients with heart failure and is related with adverse outcomes and poor quality of life. Previous experimental studies have shown biological connections between iron homeostasis, mitochondrial metabolism, and myocardial function. However, the mechanisms involved in this crosstalk are yet to be unfolded. Methods: The present research attempts to investigate the intrinsic biological mechanisms between heart failure and iron deficiency and to identify potential prognostic biomarkers by determining the gene expression pattern in the blood of heart failure patients, using whole transcriptome and targeted TaqMan^® low-density array analyses. Results: We performed a stepwise cross-sectional longitudinal study in a cohort of chronic heart failure patients with and without systemic iron deficiency. First, the full transcriptome was performed in a nested case-control exploratory cohort of 7 paired patients and underscored 1128 differentially expressed transcripts according to iron status (cohort1#). Later, we analyzed the messenger RNA levels of 22 genes selected by their statistical significance and pathophysiological relevance, in a validation cohort of 71 patients (cohort 2#). Patients with systemic iron deficiency presented lower mRNA levels of mitochondrial ferritin, sirtuin-7, small integral membrane protein 20, adrenomedullin and endothelin converting enzyme-1. An intermediate mitochondrial ferritin gene expression and an intermediate or low sirtuin7 and small integral membrane protein 20 mRNA levels were associated with an increased risk of all-cause mortality and heart failure admission ((HR 2.40, 95% CI 1.04–5.50, p-value = 0.039), (HR 5.49, 95% CI 1.78–16.92, p-value = 0.003), (HR 9.51, 95% CI 2.69–33.53, p-value < 0.001), respectively). Conclusions: Patients with chronic heart failure present different patterns of blood gene expression depending on systemic iron status that affect pivotal genes involved in iron regulation, mitochondrial metabolism, endothelial function and cardiovascular physiology, and correlate with adverse clinical outcomes.

Prevalence of iron deficiency and red blood cell transfusions in surgical patients

Background and Objectives

While iron deficiency (ID) is the most common cause of anaemia, little is known about the prevalence and type of ID in preoperative surgical patients. The aims of the present study were to investigate the prevalence and types of ID in a large cohort of surgical patients, and how these are related to perioperative blood use after correction for confounders such as haemoglobin level.

Materials and Methods

Data were retrospectively extracted from electronic case records of all patients who underwent elective surgery between September 2016 and November 2017 (n = 2711). Iron parameters, haemoglobin and details of perioperative red cell transfusions were collected.

Results

Of 2711 patients, 618 (22.8%) were iron deficient (= transferrin saturation [TSAT] < 16%) preoperatively, 173 (6.4% of the cohort) had an absolute iron deficiency (AID; TSAT < 16% and ferritin < 30 μg/L) and 445 (16.4%) had functional/mixed ID (TSAT < 16% and ferritin ≥ 30 μg/L). Corrected for Hb level, iron‐deficient patients received significantly more red cell units than patients without ID (p = 0.026). AID was not associated with a significantly higher incidence of transfusions (7.5% of patients transfused; p = 0.12 after correction for Hb) than patients without ID, whereas patients with functional/mixed deficiency did receive significantly more transfusions (6.1%; p = 0.021) as compared to patients without ID (1.7%).

Conclusion

Preoperative ID, in particular the functional/mixed type, was associated with a higher risk of receiving perioperative red cell transfusions as compared to patients without ID. Adequately treating ID might, therefore, reduce the need for perioperative red cell transfusions.

Prognostic impact of iron deficiency in acute coronary syndromes

BACKGROUND

Iron deficiency (IDef) is a prevalent condition in patients with heart disease and in those with heart failure (HF). Evidence has shown that this deficit is associated with worse prognosis. Data in literature are scarce on the prognostic impact of IDef in acute coronary syndromes (ACS), which is the main objective of this study.

METHODS

Observational, retrospective study which included 817 patients admitted for ACS. Two groups were defined according to the presence (n=298) or absence of IDef (n=519) on admission. The clinical event under study was the occurrence of death or severe HF in the long term. Independent predictors of prognosis were determined with logistic regression analysis.

RESULTS

Thirty-six percent of patients had IDef. There was higher mortality (p=0.004), higher incidence of HF (p=0.011) during follow-up and a higher rate of hospital readmissions (p=0.048) in this group. IDef was an independent predictor of death or severe HF in follow-up, along with anemia, left ventricular dysfunction, renal dysfunction and the absence of revascularization. IDef also enabled us to further stratify the prognosis of patients without anemia based on the occurrence of death or severe HF and those with lower Killip classes (≤2) based on the occurrence of death.

CONCLUSION

IDef was an independent predictor of death or severe HF in patients admitted with ACS and enabled additional stratification for those without anemia on admission and in those with Killip classes ≤2.

The relationship between self-care, long-term mortality, and heart failure hospitalization: insights from a real-world cohort study

AIMS

The assumption that improved self-care in the setting of heart failure (HF) care necessarily translates into improvements in long-term mortality and/or hospitalization is not well established. We aimed to study the association between self-care and long-term mortality and other major adverse HF events (MAHFE).

METHODS AND RESULTS

We conducted an observational, prospective, cohort study of 1123 consecutive patients with chronic HF. The primary endpoint was all-cause mortality. We used the European Heart Failure Self-care Behaviour Scale 9-item version (EHFSCBS-9) to measure global self-care (overall score) and three specific dimensions of self-care including autonomy-based adherence, consulting behaviour and provider-based adherence. After a mean follow-up of 3.3 years, all-cause death occurred in 487 patients (43%). In adjusted analysis, higher EHFScBS-9 scores (better self-care) at baseline were associated with lower risk of all-cause death [hazard ratio (HR) 0.993, 95% confidence interval (CI) (0.988-0.997), P-value = 0.002], cardiovascular (CV) death [HR 0.989, 95% CI (0.981-0.996), P-value = 0.003], HF hospitalization [HR 0.993, 95% CI (0.988-0.998), P-value = 0.005], and the combination of MAHFE [HR 0.995, 95% CI (0.991-0.999), P-value = 0.018]. Similarly, impaired global self-care [HR 1.589, 95% CI (1.201-2.127), P-value = 0.001], impaired autonomy-based adherence [HR 1.464, 95% CI (1.114-1.923), P-value = 0.006], and impaired consulting behaviour dimensions [HR 1.510, 95% CI (1.140-1.923), P-value = 0.006] were all associated with higher risk of all-cause mortality.

CONCLUSION

In this study, we have shown that worse self-care is an independent predictor of long-term mortality (both, all-cause and CV), HF hospitalization, and the combinations of these endpoints in patients with chronic HF. Important dimensions of self-care such as autonomy-based adherence and consulting behaviour also determine the risk of all these outcomes in the long term.

Neurohormonal activation induces intracellular iron deficiency and mitochondrial dysfunction in cardiac cells

Background

Iron deficiency (ID) is common in patients with heart failure (HF) and is associated with poor outcomes, yet its role in the pathophysiology of HF is not well-defined. We sought to determine the consequences of HF neurohormonal activation in iron homeostasis and mitochondrial function in cardiac cells.

Methods

HF was induced in C57BL/6 mice by using isoproterenol osmotic pumps and embryonic rat heart-derived H9c2 cells were subsequently challenged with Angiotensin II and/or Norepinephrine. The expression of several genes and proteins related to intracellular iron metabolism were assessed by Real time-PCR and immunoblotting, respectively. The intracellular iron levels were also determined. Mitochondrial function was analyzed by studying the mitochondrial membrane potential, the accumulation of radical oxygen species (ROS) and the adenosine triphosphate (ATP) production.

Results

Hearts from isoproterenol-stimulated mice showed a decreased in both mRNA and protein levels of iron regulatory proteins, transferrin receptor 1, ferroportin 1 and hepcidin compared to control mice. Furthermore, mitoferrin 2 and mitochondrial ferritin were also downregulated in the hearts from HF mice. Similar data regarding these key iron regulatory molecules were found in the H9c2 cells challenged with neurohormonal stimuli. Accordingly, a depletion of intracellular iron levels was found in the stimulated cells compared to non-stimulated cells, as well as in the hearts from the isoproterenol-induced HF mice. Finally, neurohormonal activation impaired mitochondrial function as indicated by the accumulation of ROS, the impaired mitochondrial membrane potential and the decrease in the ATP levels in the cardiac cells.

Conclusions

HF characteristic neurohormonal activation induced changes in the regulation of key molecules involved in iron homeostasis, reduced intracellular iron levels and impaired mitochondrial function. The current results suggest that iron could be involved in the pathophysiology of HF.

Prognostic impact of iron deficiency in acute coronary syndromes

BACKGROUND

Iron deficiency (IDef) is a prevalent condition in patients with heart disease and in those with heart failure (HF). Evidence has shown that this deficit is associated with a worse prognosis. There is only a small amount of data in the literature regarding the prognostic impact of IDef in acute coronary syndromes (ACS), which is the main objective of this study.

METHODS

Observational, retrospective study which included 817 patients admitted for ACS. Two groups were defined according to the presence (n = 298) or absence of IDeF (n = 519) on admission. The clinical event under study was the occurrence of death or severe HF in long term. Independent predictors of prognosis were determined with logistic regression analysis.

RESULTS

36% of patients had IDef. These patients had a higher mortality rate (p = 0.004), higher incidence of HF (p = 0.011) during follow-up and a higher rate of hospital readmissions (p = 0.048). IDef was an independent predictor of death or severe HF in follow-up, along with anemia, left ventricular dysfunction, renal dysfunction and the absence of revascularization. Besides, IDef also enabled us to further stratify the prognosis of patients without anemia based on the occurrence of death or severe HF and those with lower Killip classes (≤2) based on the occurrence of death.

CONCLUSION

IDef was an independent predictor of death or severe HF in patients admitted with ACS and enabled additional stratification for those without anemia on admission and in those with Killip classes ≤2.

High soluble transferrin receptor in patients with heart failure: a measure of iron deficiency and a strong predictor of mortality

AIMS

Iron deficiency (ID) is frequent in heart failure (HF), linked with exercise intolerance and poor prognosis. Intravenous iron repletion improves clinical status in HF patients with left ventricular ejection fraction (LVEF) ≤45%. However, uncertainty exists about the accuracy of serum biomarkers in diagnosing ID. The aims of this study were (i) to identify the iron biomarker with the greatest accuracy for the diagnosis of ID in bone marrow in patients with ischaemic HF, and (ii) to establish the prevalence of ID using this biomarker and its prognostic value in HF patients.

METHODS AND RESULTS

Bone marrow was stained for iron in 30 patients with ischaemic HF with LVEF ≤45% and 10 healthy controls, and ID was diagnosed for 0-1 grades (Gale scale). A total of 791 patients with HF with LVEF ≤45% were prospectively followed up for 3 years. Serum ferritin, transferrin saturation, soluble transferrin receptor (sTfR) were assessed as iron biomarkers. Most patients with HF (n = 25, 83%) had ID in bone marrow, but none of the controls (P < 0.001). Serum sTfR had the best accuracy in predicting ID in bone marrow (area under the curve 0.920, 95% confidence interval 0.761-0.987, for cut-off 1.25 mg/L sensitivity 84%, specificity 100%). Serum sTfR was ≥1.25 mg/L in 47% of HF patients, in 56% and 46% of anaemics and non-anaemics, respectively (P < 0.05). The reclassification methods revealed that serum sTfR significantly added the prognostic value to the baseline prognostic model, and to the greater extent than plasma N-terminal pro B-type natriuretic peptide. Based on internal derivation and validation procedures, serum sTfR ≥1.41 mg/L was the optimal threshold for predicting 3-year mortality, independent of other established variables.

CONCLUSIONS

High serum sTfR accurately reflects depleted iron stores in bone marrow in patients with HF, and identifies those with a high 3-year mortality.

Use of intravenous iron in patients with iron deficiency and chronic heart failure: Real-world evidence

INTRODUCTION AND OBJECTIVES

Treatment with intravenous iron in patients with heart failure (HF) and iron deficiency (ID) improves symptoms, however its impact on survival and safety is unknown. We aimed to evaluate the management of ID and anemia with intravenous iron in patients with HF and long-term safety of intravenous iron.

METHODS

We evaluated anemia and ID in patients with chronic HF at 3 university hospitals. Anemia was defined using the World Health Organization definition and ID was defined as ferritin <100 ug/L or a Transferrin Saturation <20% if ferritin between 100 and 299 ug/L. We assessed treatment with intravenous iron during follow-up and its association with mortality and HF hospitalizations using multivariate cox regression analysis.

RESULTS

We included 2,114 patients, median age 72 years and 57% had reduced left ventricular ejection fraction. ID was present in 55% and ID and anemia in 29%. Treatment with intravenous iron was used in 24% of patients with ID and 34% of patients with ID and anemia. In patients with ID, after multivariate adjustment, treatment with intravenous iron was associated with lower all-cause mortality: HR = 0.38 (0.28-0.56), lower cardiovascular mortality: HR = 0.34 (0.20-0.57) and no differences in HF hospitalizations: HR = 1.15 (0.88-1.50). Similar outcomes were found for patients with anemia and ID.

CONCLUSIONS

In a real-world cohort of patients with HF, treatment with intravenous iron was used in one third of patients with ID and anemia and appears safe in mid-term follow-up.

Iron Deficiency: Impact on Functional Capacity and Quality of Life in Heart Failure with Preserved Ejection Fraction

The effects of iron deficiency (ID) have been widely studied in heart failure (HF) with reduced ejection fraction. On the other hand, studies in HF with preserved ejection fraction (HFpEF) are few and have included small numbers of participants. The aim of this study was to assess the role that ID plays in functional capacity and quality of life (QoL) in HFpEF while comparing several iron-related biomarkers to be used as potential predictors. ID was defined as ferritin <100 ng/mL or transferrin saturation <20%. Submaximal exercise capacity, measured by the 6-min walking test (6MWT), and QoL, assessed by the Minnesotta Living with Heart Failure Questionnaire (MLHFQ), were compared between iron deficient patients and patients with normal iron status. A total of 447 HFpEF patients were included in the present cross-sectional study, and ID prevalence was 73%. Patients with ID performed worse in the 6MWT compared to patients with normal iron status (ID 271 ± 94 m vs. non-ID 310 ± 108 m, p < 0.01). They also scored higher in the MLHFQ, denoting worse QoL (ID 49 ± 22 vs. non-ID 43 ± 23, p = 0.01). Regarding iron metabolism biomarkers, serum soluble transferrin receptor (sTfR) was the strongest independent predictor of functional capacity (β = −63, p < 0.0001, R² 0.39) and QoL (β = 7.95, p < 0.0001, R² 0.14) in multivariate models. This study postulates that ID is associated with worse functional capacity and QoL in HFpEF as well, and that sTfR is the best iron-related biomarker to predict both. Our study also suggests that the effects of ID could differ among HFpEF patients by left ventricular ejection fraction.

Association Between Norepinephrine Levels and Abnormal Iron Status in Patients With Chronic Heart Failure: Is Iron Deficiency More Than a Comorbidity?

Background

Mechanisms underlying iron homeostasis dysregulation in patients with chronic heart failure remain unsettled. In cardiomyocyte models, norepinephrine may lead to intracellular iron depletion, but the potential association between catecholamines (sympathetic activation markers) and iron metabolism biomarkers in chronic heart failure is unknown.

Methods and Results

In this cross‐sectional analysis, we studied the association between plasma norepinephrine levels and serum iron status biomarkers indicating iron storage (ferritin), iron transport (transferrin saturation), and iron demand (soluble transferrin receptor) in a prospective cohort of 742 chronic heart failure patients (mean age, 72±11 years; 56% male). Impaired iron status was defined as ferritin <100 μg/L or transferrin saturation <20%. Impaired iron status was observed in 69% of patients. In multivariate models, greater norepinephrine levels were associated with impaired iron transport (transferrin saturation <20%, odds ratio=2.28; 95% CI [1.19–4.35]; P=0.013), but not with impaired iron storage (ferritin <100 μg/L, odds ratio=1.25; 95% CI [0.73–2.16]; P=0.415). Norepinephrine was a significant predictor of increased iron demand (soluble transferrin receptor, standardized β‐coefficient=0.12; P=0.006) and low transferrin saturation (standardized β‐coefficient=−0.12; P=0.003). However, norepinephrine levels were not associated with iron or ferritin levels (P>0.05). Adjusted norepinephrine marginal means were significantly higher in patients with impaired iron status compared with those with normal iron status (528 pg/mL [505–551] versus 482 pg/mL [448–518], respectively; P=0.038).

Conclusions

In chronic heart failure patients, increased sympathetic activation estimated with norepinephrine levels is associated with impaired iron status and, particularly, dysregulation of biomarkers suggesting impaired iron transport and increased iron demand. Whether the relationship between norepinephrine and iron metabolism is bidirectional and entails causality need to be elucidated in future research.

Iron deficiency anaemia revisited

Iron deficiency anaemia is a global health concern affecting children, women and the elderly, whilst also being a common comorbidity in multiple medical conditions. The aetiology is variable and attributed to several risk factors decreasing iron intake and absorption or increasing demand and loss, with multiple aetiologies often coexisting in an individual patient. Although presenting symptoms may be nonspecific, there is emerging evidence on the detrimental effects of iron deficiency anaemia on clinical outcomes across several medical conditions. Increased awareness about the consequences and prevalence of iron deficiency anaemia can aid early detection and management. Diagnosis can be easily made by measurement of haemoglobin and serum ferritin levels, whilst in chronic inflammatory conditions, diagnosis may be more challenging and necessitates consideration of higher serum ferritin thresholds and evaluation of transferrin saturation. Oral and intravenous formulations of iron supplementation are available, and several patient and disease-related factors need to be considered before management decisions are made. This review provides recent updates and guidance on the diagnosis and management of iron deficiency anaemia in multiple clinical settings.

Micronutrient Depletion in Heart Failure: Common, Clinically Relevant and Treatable

Heart failure (HF) is a chronic condition with many imbalances, including nutritional issues. Next to sarcopenia and cachexia which are clinically evident, micronutrient deficiency is also present in HF. It is involved in HF pathophysiology and has prognostic implications. In general, most widely known micronutrients are depleted in HF, which is associated with symptoms and adverse outcomes. Nutritional intake is important but is not the only factor reducing the micronutrient availability for bodily processes, because absorption, distribution, and patient comorbidity may play a major role. In this context, interventional studies with parenteral micronutrient supplementation provide evidence that normalization of micronutrients is associated with improvement in physical performance and quality of life. Outcome studies are underway and should be reported in the following years.

The Burden of Iron Deficiency in Heart Failure: Therapeutic Approach

Heart failure (HF) is highlighted by its burdening symptom-limited exercise capacity and recurrent hospitalizations. Despite substantial advances regarding disease-modifying drugs in HF with reduced ejection fraction, additional therapeutic strategies to improve quality of life are invaluable. Currently, iron deficiency (ID) is overwhelmingly recognized in over 30% to 50% of patients with stable chronic HF, which worsens prognosis. The established pathophysiological mechanisms of progressive HF may be intertwined with increasing myocardial iron scarcity, wherein one begets the other. Most importantly, ID constitutes a novel target for symptom relief in carefully selected patients. In this regard, intravenous iron may be a safe and efficacious intervention, potentially reducing HF hospitalizations. We discuss the evidence and gaps in knowledge concerning iron therapy in HF and propose a practical, comprehensive, clinically oriented algorithm for timely adequate iron replenishment in different clinical scenarios. Finally, we further debate imperative decision-making before intervention and the drawbacks of such a strategy.

Myocardial Energetics and Heart Failure: a Review of Recent Therapeutic Trials

PURPOSE OF REVIEW

Several novel therapeutics being tested in patients with heart failure are based on myocardial energetics. This review will provide a summary of the recent trials in this area, including therapeutic options targeting various aspects of cellular and mitochondrial metabolism.

RECENT FINDINGS

Agents that improve the energetic balance in myocardial cells have the potential to improve clinical heart failure status. The most promising therapies currently under investigation in this arena include (1) elamipretide, a cardiolipin stabilizer; (2) repletion of iron deficiency with intravenous ferrous carboxymaltose; (3) coenzyme Q10; and (4) the partial adenosine receptor antagonists capadenoson and neladenosone. Myocardial energetics-based therapeutics are groundbreaking in that they utilize novel mechanisms of action to improve heart failure symptoms, without causing the adverse neurohormonal side effects associated with current guideline-based therapies. The drugs appear likely to be added to the heart failure therapy armamentarium as adjuncts to current regimens in the near future.

Established and Emerging Concepts to Treat Imbalances of Iron Homeostasis in Inflammatory Diseases

Inflammation, being a hallmark of many chronic diseases, including cancer, inflammatory bowel disease, rheumatoid arthritis, and chronic kidney disease, negatively affects iron homeostasis, leading to iron retention in macrophages of the mononuclear phagocyte system. Functional iron deficiency is the consequence, leading to anemia of inflammation (AI). Iron deficiency, regardless of anemia, has a detrimental impact on quality of life so that treatment is warranted. Therapeutic strategies include (1) resolution of the underlying disease, (2) iron supplementation, and (3) iron redistribution strategies. Deeper insights into the pathophysiology of AI has led to the development of new therapeutics targeting inflammatory cytokines and the introduction of new iron formulations. Moreover, the discovery that the hormone, hepcidin, plays a key regulatory role in AI has stimulated the development of several therapeutic approaches targeting the function of this peptide. Hence, inflammation-driven hepcidin elevation causes iron retention in cells and tissues. Besides pathophysiological concepts and diagnostic approaches for AI, this review discusses current guidelines for iron replacement therapies with special emphasis on benefits, limitations, and unresolved questions concerning oral versus parenteral iron supplementation in chronic inflammatory diseases. Furthermore, the review explores how therapies aiming at curing the disease underlying AI can also affect anemia and discusses emerging hepcidin antagonizing drugs, which are currently under preclinical or clinical investigation.

Screening, diagnosis and treatment of iron deficiency in chronic heart failure: putting the 2016 European Society of Cardiology heart failure guidelines into clinical practice

Iron deficiency is common in patients with chronic heart failure (CHF) and is associated with reduced exercise performance, impaired health-related quality of life and an increased risk of mortality, irrespective of whether or not anaemia is present. Iron deficiency is a serious but treatable condition. Several randomized controlled clinical trials have demonstrated the ability of intravenous (IV) iron, primarily IV ferric carboxymaltose (FCM), to correct iron deficiency in patients with heart failure with reduced ejection fraction (HFrEF), resulting in improvements in exercise performance, CHF symptoms and health-related quality of life. The importance of addressing the issue of iron deficiency in patients with CHF is reflected in the 2016 European Society of Cardiology (ESC) heart failure guidelines, which recognize iron deficiency as an important co-morbidity, independent of anaemia. These guidelines recommend that all newly diagnosed heart failure patients are routinely tested for iron deficiency and that IV FCM should be considered as a treatment option in symptomatic patients with HFrEF and iron deficiency (serum ferritin < 100 µg/L, or ferritin 100-299 µg/L and transferrin saturation < 20%). Despite these specific recommendations, there is still a lack of practical, easy-to-follow advice on how to diagnose and treat iron deficiency in clinical practice. This article is intended to complement the current 2016 ESC heart failure guidelines by providing practical guidance to all health care professionals relating to the procedures for screening, diagnosis and treatment of iron deficiency in patients with CHF.

Iron deficiency in chronic heart failure: case-based practical guidance

In patients with chronic heart failure, iron deficiency, even in the absence of anaemia, can aggravate the underlying disease and have a negative impact on clinical outcomes and quality of life. The 2016 European Society of Cardiology guidelines for the diagnosis and treatment of acute and chronic heart failure recognize iron deficiency as a co‐morbidity in chronic heart failure and recommend iron status screening in all newly diagnosed patients with chronic heart failure. Furthermore, the guidelines specifically recommend considerations of intravenous iron therapy, ferric carboxymaltose, for the treatment of iron deficiency. However, in spite of these recommendations, iron deficiency remains often overlooked and undertreated. This may be due, in part, to the lack of clinical context and practical guidance accompanying the guidelines for the treating physician. Here, we provide practical guidance complemented by a case study to assist and improve the timely diagnosis, treatment, and routine management of iron deficiency in patients with chronic heart failure.

Iron status in the elderly: A review of recent evidence

A comprehensive literature review of iron status in the elderly was undertaken in order to update a previous review (Fairweather-Tait et al, 2014); 138 summarised papers describe research on the magnitude of the problem, aetiology and age-related physiological changes that may affect iron status, novel strategies for assessing iron status with concurrent health conditions, hepcidin, lifestyle factors, iron supplements, iron status and health outcomes (bone mineral density, frailty, inflammatory bowel disease, kidney failure, cancer, cardiovascular, and neurodegenerative diseases). Each section of this review concludes with key points from the relevant papers. The overall findings were that disturbed iron metabolism plays a major role in a large number of conditions associated with old age. Correction of iron deficiency/overload may improve disease prognosis, but diagnosis of iron deficiency requires appropriate cut-offs for biomarkers of iron status in elderly men and women to be agreed. Iron deficiency (with or without anemia), anemia of inflammation, and anemia of chronic disease are all widespread in the elderly and, once identified, should be investigated further as they are often indicative of underlying disease. Management options should be reviewed and updated, and novel therapies, which show potential for treating anemia of inflammation or chronic disease, should be considered.

Depleted iron stores are associated with inspiratory muscle weakness independently of skeletal muscle mass in men with systolic chronic heart failure

BACKGROUND

Skeletal and respiratory muscle dysfunction constitutes an important pathophysiological feature of heart failure (HF). We assessed the relationships between respiratory muscle function, skeletal muscle mass, and physical fitness in men with HF with reduced left ventricular ejection fraction (HFrEF), and investigated the hypothesis of whether iron deficiency (ID) contributes to respiratory muscle dysfunction in these patients.

METHODS

We examined 53 male outpatients with stable HFrEF without asthma or chronic obstructive pulmonary disease (age: 64 ± 10 years; New York Heart Association [NYHA] class I/II/III: 36/51/13%; ischaemic aetiology: 83%; all with left ventricular ejection fraction ≤40%) and 10 middle-aged healthy men (control group). We analysed respiratory muscle function (maximal inspiratory and expiratory pressure at the mouth [MIP and MEP, respectively]), appendicular lean mass/body mass index (ALM/BMI; ALM was measured using dual-energy X-ray absorptiometry), physical fitness (components of Functional Fitness Test for Older Adults), and iron status.

RESULTS

MIP, MEP, and ALM/BMI (but not MIP adjusted for ALM/BMI) were lower in men with HFrEF vs. healthy men. MIP, MEP, and MIP adjusted for ALM/BMI (but not ALM/BMI) were lower in men with HFrEF with vs. without ID. In a multivariable linear regression model lower serum ferritin (but not transferrin saturation) was associated with lower MIP independently of ALM/BMI, left ventricular ejection fraction, N-terminal pro-B-type natriuretic peptide (NT-proBNP), and haemoglobin concentration. In multivariable linear regression models, lower MIP was associated with worse results in Functional Fitness Test when adjusted for ALM/BMI or relevant clinical variables (NYHA class, estimated glomerular filtration rate, NT-proBNP, and haemoglobin concentration).

CONCLUSIONS

In men with HFrEF, low ferritin reflecting depleted iron stores is associated with inspiratory muscle weakness independently of skeletal muscle mass. Inspiratory muscle dysfunction correlates with worse physical fitness independently of either skeletal muscle mass or disease severity.

Iron deficiency across chronic inflammatory conditions: International expert opinion on definition, diagnosis, and management

Iron deficiency, even in the absence of anemia, can be debilitating, and exacerbate any underlying chronic disease, leading to increased morbidity and mortality. Iron deficiency is frequently concomitant with chronic inflammatory disease; however, iron deficiency treatment is often overlooked, partially due to the heterogeneity among clinical practice guidelines. In the absence of consistent guidance across chronic heart failure, chronic kidney disease and inflammatory bowel disease, we provide practical recommendations for iron deficiency to treating physicians: definition, diagnosis, and disease‐specific diagnostic algorithms. These recommendations should facilitate appropriate diagnosis and treatment of iron deficiency to improve quality of life and clinical outcomes.

Peak Exercise Oxygen Uptake Predicts Recurrent Admissions in Heart Failure With Preserved Ejection Fraction

INTRODUCTION AND OBJECTIVES

Heart failure with preserved ejection fraction (HFpEF) is a highly prevalent syndrome with an elevated risk of morbidity and mortality. To date, there is scarce evidence on the role of peak exercise oxygen uptake (peak VO₂) for predicting the morbidity burden in HFpEF. We sought to evaluate the association between peak VO₂ and the risk of recurrent hospitalizations in patients with HFpEF.

METHODS

A total of 74 stable symptomatic patients with HFpEF underwent a cardiopulmonary exercise test between June 2012 and May 2016. A negative binomial regression method was used to determine the association between the percentage of predicted peak VO₂ (pp-peak VO₂) and recurrent hospitalizations. Risk estimates are reported as incidence rate ratios.

RESULTS

The mean age was 72.5 ± 9.1 years, 53% were women, and all patients were in New York Heart Association functional class II to III. Mean peak VO₂ and median pp-peak VO₂ were 10 ± 2.8mL/min/kg and 60% (range, 47-67), respectively. During a median follow-up of 276 days [interquartile range, 153-1231], 84 all-cause hospitalizations in 31 patients (41.9%) were registered. A total of 15 (20.3%) deaths were also recorded. On multivariate analysis, accounting for mortality as a terminal event, pp-peak VO₂ was independently and linearly associated with the risk of recurrent admission. Thus, and modeled as continuous, a 10% decrease of pp-peak VO₂ increased the risk of recurrent hospitalizations by 32% (IRR, 1.32; 95%CI, 1.03-1.68; P = .028).

CONCLUSIONS

In symptomatic elderly patients with HFpEF, pp-peak VO₂ predicts all-cause recurrent admission.

Management of anemia in patients with congestive heart failure

Anemia is an independent risk factor for adverse patient outcomes. There are no guidelines for management of anemia in patients with congestive heart failure (CHF), despite its high incidence. Four objectives were defined by the International Anemia Management and Clinical Outcomes Expert Panel (AMCO), a multinational group of interdisciplinary experts identified by the Society for the Advancement of Blood Management (SABM) to: determine the prevalence of anemia in outpatients; to determine the prevalence of hospital-acquired anemia; to assess the impact of anemia management on clinical outcomes such as quality of life and functional status; and to provide recommendations for primary care physicians and specialists for the diagnosis, evaluation, and management of anemia in patients with CHF. Anemia and iron deficiency were confirmed to be highly prevalent in patients with CHF. Intravenous iron therapy improves anemia, cardiac function and exercise tolerance, leading to improvement in quality of life. Anemia management has been demonstrated to be cost-effective. Clinical care pathways to manage anemia in patients with CHF are recommended as best practices in order to improve patient outcomes. Am. J. Hematol. 92:88-93, 2017. © 2016 Wiley Periodicals, Inc.

Iron Deficiency Treatment in Patients with Heart Failure

Iron deficiency (ID) is one of the major risk factors for disability and mortality worldwide, and it was identified as a common and ominous comorbidity in patients with heart failure (HF), both with and without anaemia. Based on two clinical trials (FAIR-HF and CONFIRM-HF) and other epidemiological evidence, ID has been recognized as an important therapeutic target in symptomatic patients with HF and LVEF ≤45%.Intravenous iron supplementation has been demonstrated to be safe and effective for iron repletion and related with an improvement in clinical status, exercise capacity, and quality of life. Ongoing trials are testing the hypothesis that such a therapy may also reduce the risk of HF hospitalizations and cardiovascular death.

Iron Deficiency Is a Determinant of Functional Capacity and Health-related Quality of Life 30 Days After an Acute Coronary Syndrome

BACKGROUND AND OBJECTIVES

Iron deficiency (ID) is a prevalent condition in patients with ischemic heart disease and heart failure. Little is known about the impact of ID on exercise capacity and quality of life (QoL) in the recovery phase after an acute coronary syndrome (ACS).

METHODS

Iron status and its impact on exercise capacity and QoL were prospectively evaluated in 244 patients 30 days after the ACS. QoL was assessed by the standard EuroQoL-5 dimensions, EuroQoL visual analogue scale, and Heart-QoL questionnaires. Exercise capacity was analyzed by treadmill/6-minute walk tests. The effect of ID on cardiovascular mortality and readmission rate was also investigated.

RESULTS

A total of 46% of the patients had ID. These patients had lower exercise times (366±162 vs 462±155seconds; P<.001), metabolic consumption rates (7.9±2.9 vs 9.3±2.6 METS; P=.003), and EuroQoL-5 dimensions (0.76±0.25 vs 0.84±0.16), visual analogue scale (66±16 vs 72±17), and Heart-QoL (1.9±0.6 vs 2.2±0.6) scores (P<.05). ID independently predicted lower exercise times (OR, 2.9; 95%CI, 1.1-7.6; P=.023) and worse QoL (OR, 1.9; 95%CI, 1.1-3.3; P<.001) but had no effect on cardiovascular morbidity or mortality.

CONCLUSIONS

ID, a prevalent condition in ACS patients, results in a poorer mid-term functional recovery, as measured by exercise capacity and QoL.