Iron deficiency in heart failure with preserved ejection fraction: a systematic review and meta-analysis

Heart failure with preserved ejection fraction epidemiology, pathophysiology, diagnosis and treatment strategies

The prevalence of HF with preserved ejection raction (HFpEF, with EF ≥50%) is increasing across all populations with high rates of hospitalization and mortality, reaching up to 80% and 50%, respectively, within a 5-year timeframe. Comorbidity-driven systemic inflammation is thought to cause coronary microvascular dysfunction and increased epicardial adipose tissue, leading to downstream friborsis and molecular changes in the cardiomyocyte, leading to increased stiffness and diastolic dynsfunction. HFpEF poses unique challenges in terms of diagnosis due to its complex and diverse nature. The diagnosis of HFpEF relies on a combination of clinical assessment, imaging studies, and biomarkers. An additional important step in diagnosing HFpEF involves excluding certain cardiac diagnoses that may be specific underlying causes of HFpEF or may be masquerading as HFpEF and require specific alternative treatment approaches. In addition to administering sodium-glucose cotransporter 2 inhibitors to all patients, the most effective approach to enhance clinical outcomes may involve tailored therapy based on each patient's unique clinical profile. Exercise should be recommended for all patients to improve the quality of life. Glucagon-like peptide-1 1 agonists are a promising treatment option in obese HFpEF patients. Novel approaches targeting inflammation are also in early phase trials.

Heart failure with preserved ejection fraction: diagnosis, risk assessment, and treatment

The aetiology of heart failure with preserved ejection fraction (HFpEF) is heterogenous and overlaps with that of several comorbidities like atrial fibrillation, diabetes mellitus, chronic kidney disease, valvular heart disease, iron deficiency, or sarcopenia. The diagnosis of HFpEF involves evaluating cardiac dysfunction through imaging techniques and assessing increased left ventricular filling pressure, which can be measured directly or estimated through various proxies including natriuretic peptides. To better narrow down the differential diagnosis of HFpEF, European and American heart failure guidelines advocate the use of different algorithms including comorbidities that require diagnosis and rigorous treatment during the evaluation process. Therapeutic recommendations differ between guidelines. Whilst sodium glucose transporter 2 inhibitors have a solid evidence base, the recommendations differ with regard to the use of inhibitors of the renin-angiotensin-aldosterone axis. Unless indicated for specific comorbidities, the use of beta-blockers should be discouraged in HFpEF. The aim of this article is to provide an overview of the current state of the art in HFpEF diagnosis, clinical evaluation, and treatment.

Ferric carboxymaltose and exercise capacity in heart failure with preserved ejection fraction and iron deficiency: the FAIR-HFpEF trial

BACKGROUND AND AIMS

Evidence is lacking that correcting iron deficiency (ID) has clinically important benefits for patients with heart failure with preserved ejection fraction (HFpEF).

METHODS

FAIR-HFpEF was a multicentre, randomized, double-blind trial designed to compare intravenous ferric carboxymaltose (FCM) with placebo (saline) in 200 patients with symptomatic HFpEF and ID (serum ferritin < 100 ng/mL or ferritin 100-299 ng/mL with transferrin saturation < 20%). The primary endpoint was change in 6-min walking test distance (6MWTD) from baseline to week 24. Secondary endpoints included changes in New York Heart Association class, patient global assessment, and health-related quality of life (QoL).

RESULTS

The trial was stopped because of slow recruitment after 39 patients had been included (median age 80 years, 62% women). The change in 6MWTD from baseline to week 24 was greater for those assigned to FCM compared to placebo [least square mean difference 49 m, 95% confidence interval (CI) 5-93; P = .029]. Changes in secondary endpoints were not significantly different between groups. The total number of adverse events (76 vs. 114) and serious adverse events (5 vs. 19; rate ratio 0.27, 95% CI 0.07-0.96; P = .043) was lower with FCM than placebo.

CONCLUSIONS

In patients with HFpEF and markers of ID, intravenous FCM improved 6MWTD and was associated with fewer serious adverse events. However, the trial lacked sufficient power to identify or refute effects on symptoms or QoL. The potential benefits of intravenous iron in HFpEF with ID should be investigated further in a larger cohort.

Heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) accounts for nearly half of all heart failure cases and has a prevalence that is expected to rise with the growing ageing population. HFpEF is associated with significant morbidity and mortality. Specific HFpEF risk factors include age, diabetes, hypertension, obesity and atrial fibrillation. Haemodynamic contributions to HFpEF include changes in left ventricular structure, diastolic and systolic dysfunction, left atrial myopathy, pulmonary hypertension, right ventricular dysfunction, chronotropic incompetence, and vascular dysfunction. Inflammation, fibrosis, impaired nitric oxide signalling, sarcomere dysfunction, and mitochondrial and metabolic defects contribute to the cellular and molecular changes observed in HFpEF. HFpEF impacts multiple organ systems beyond the heart, including the skeletal muscle, peripheral vasculature, lungs, kidneys and brain. The diagnosis of HFpEF can be made in individuals with signs and symptoms of heart failure with abnormality in natriuretic peptide levels or evidence of cardiopulmonary congestion, facilitated by the use of HFpEF risk scores and additional imaging and testing with the exclusion of HFpEF mimics. Management includes initiation of guideline-directed medical therapy and management of comorbidities. Given the significant impact of HFpEF on quality of life, future research efforts should include a particular focus on how patients can live better with this disease.

Biomarkers in Heart Failure with Preserved Ejection Fraction: A Perpetually Evolving Frontier

Heart failure with preserved ejection fraction (HFpEF) represents a complex clinical syndrome, often very difficult to diagnose using the available tools. As the global burden of this disease is constantly growing, surpassing the prevalence of heart failure with reduced ejection fraction, during the last few years, efforts have focused on optimizing the diagnostic and prognostic pathways using an immense panel of circulating biomarkers. After the paradigm of HFpEF development emerged more than 10 years ago, suggesting the impact of multiple comorbidities on myocardial structure and function, several phenotypes of HFpEF have been characterized, with an attempt to find an ideal biomarker for each distinct pathophysiological pathway. Acknowledging the limitations of natriuretic peptides, hundreds of potential biomarkers have been evaluated, some of them demonstrating encouraging results. Among these, soluble suppression of tumorigenesis-2 reflecting myocardial remodeling, growth differentiation factor 15 as a marker of inflammation and albuminuria as a result of kidney dysfunction or, more recently, several circulating microRNAs have proved their incremental value. As the number of emerging biomarkers in HFpEF is rapidly expanding, in this review, we aim to explore the most promising available biomarkers linked to key pathophysiological mechanisms in HFpEF, outlining their utility for diagnosis, risk stratification and population screening, as well as their limitations.

Outcomes and complications of heart failure with iron deficiency anemia: a nationwide analysis

INTRODUCTION

Heart failure is a pressing public health concern, affecting millions in the United States and projected to rise significantly by 2030. Iron deficiency, prevalent in nearly half of ambulatory heart failure patients, contributes to anemia and diminishes patient outcomes. In this study, we aim to evaluate the impact of iron deficiency anemia on acute heart failure hospitalizations outcomes.

METHODS

Utilizing the 2019 National Inpatient Sample (NIS) database, a retrospective observational study assessed 112,864 adult patients hospitalized with heart failure and 7,865 cases also had a concomitant diagnosis of iron deficiency anemia (IDA).

RESULTS

Among 112,864 heart failure hospitalizations in 2019, approximately 7% had concomitant iron deficiency anemia (IDA). Heart failure patients with IDA exhibited distinct demographic characteristics, with females comprising 51.1% (p < 0.01) and higher rates of complicated hypertension (p < 0.01), complicated diabetes (p < 0.01), and peripheral vascular disease (p < 0.01). Adjusted mean LOS for patients with IDA was significantly longer at 1.31 days (95% CI 0.71-1.47; p < 0.01), persisting in both HFpEF and HFrEF subgroups. While total hospital charges were comparable in HFpEF, HFrEF patients with IDA incurred significantly higher charges ($13427.32, 95% CI: 1463.35-$25391.29, p = 0.03) than those without IDA. Complications such as atrial fibrillation and acute kidney injury were notably more prevalent in HFpEF and HFrEF patients with IDA.

CONCLUSION

The study highlighted that iron deficiency in heart failure patients leads to extended hospital stays, increased costs, and heightened risks of specific complications, particularly in HFrEF. Our study emphasized the implications of IDA in patients with heart failure ranging from prolonged hospitalizations and increased costs. Addressing iron deficiency is crucial, given its substantial impact on heart failure hospitalizations and outcomes, emphasizing the need for proactive diagnosis and management.

Management of Iron Deficiency in Heart Failure: Practical Considerations and Implementation of Evidence-Based Iron Supplementation

Iron deficiency (ID) is present in approximately 50% of patients with heart failure (HF) and even higher prevalence rate up to 80% in post-acute HF setting. The current guidelines for HF recommend intravenous (IV) iron replacement in HF with reduced or mildly reduced ejection fraction and ID based on clinical trials showing improvements in quality of life and exercise capacity, and an overall treatment benefit for recurrent HF hospitalization. However, several barriers cause challenges in implementing IV iron supplementation in practice due, in part, to clinician knowledge gaps and limited resource availability to protocolize routine utilization in appropriate patients. Thus, the current review will discuss practical considerations in ID treatment, implementation of evidence-based ID treatment to improve regional health disparities with toolkits, inclusion/exclusion criteria of IV iron supplementation, and clinical controversies in ID treatment, as well as gaps in evidence and questions to be answered.

Intravenous iron in patients with iron deficiency and heart failure: a review of modern evidence

PURPOSE OF REVIEW

Iron deficiency is common in patients with heart failure, affecting up to half of ambulatory patients and an even greater percentage of patients admitted for acute decompensation. Iron deficiency in this population is also associated with poor outcomes, including worse quality of life in addition to increased hospitalizations for heart failure and mortality. Evidence suggests that patients with iron deficiency in heart failure may benefit from repletion with IV iron.

RECENT FINDINGS

In this review, we outline the etiology and pathophysiology of iron deficiency in heart failure as well as various iron formulations available. We discuss evidence for intravenous iron repletion with a particular focus on recent studies that have evaluated its effects on hospitalizations and mortality. Finally, we discuss areas of uncertainty and future study and provide practical guidance for iron repletion.

SUMMARY

In summary, there is overwhelming evidence that intravenous iron repletion in patients with iron deficiency in heart failure is both beneficial and safe. However, further evidence is needed to better identify which patients would most benefit from iron repletion as well as the ideal repletion strategy.

Exercise training response according to baseline ferrokinetics in heart failure with preserved ejection fraction: A substudy of the TRAINING-HF trial

BACKGROUND

Iron deficiency (ID) is associated with impaired functional capacity in patients with heart failure (HF), even in those with preserved ejection fraction (HFpEF). This study aimed to evaluate the effect of baseline ferrokinetics on peak oxygen consumption (peakVO2) improvement after a 12-week physical therapy programme in patients with stable HFpEF.

METHODS

This study is a post-hoc sub-analysis of a randomized clinical trial in which 59 stable patients with HFpEF were randomized to receive a 12-week programme of inspiratory muscle training (IMT), functional electrical stimulation (FES), IMT + FES or usual care (UC) to evaluate change in peakVO2 (NCT02638961). Serum ferritin and transferrin saturation (TSAT) determinations were assessed at baseline. ID was defined as ferritin <100 ng/mL and/or TSAT <20% if ferritin was within 100-299 ng/mL. We used a linear mixed regression model to analyse between-treatment changes in peakVO2 across ferrokinetics status at 12 and 24 weeks.

RESULTS

The mean age was 74 ± 9 years, and 36 (61%) had ID. The mean of peakVO2 was 9.9 ± 2.5 mL/kg/min. The median of ferritin and transferrin saturation (TSAT) was 91 (50-181) ng/mL and 23% (16-30), respectively. A total of 52 patients completed the trial (13 patients per arm). Compared with those patients on UC, patients allocated to any of the active arms showed less improvement in peak VO2 when they showed ID (P-value for interaction <0.001), lower values of ferritin (P-value for interaction <0.001), or TSAT (P-value for interaction <0.001).

CONCLUSIONS

Ferrokinetics status plays an essential role in modifying the aerobic capacity response to physical therapies in patients with HFpEF. Further studies are required to confirm these findings.

Advance in the pharmacological and comorbidities management of heart failure with preserved ejection fraction: evidence from clinical trials

The prevalence of heart failure with preserved ejection fraction (HFpEF) accounts for approximately 50% of the total heart failure population, and with the aging of the population and the increasing prevalence of hypertension, obesity, and type 2 diabetes (T2DM), the incidence of HFpEF continues to rise and has become the most common subtype of heart failure. Compared with heart failure with reduced ejection fraction, HFpEF has a more complex pathophysiology and is more often associated with hypertension, T2DM, obesity, atrial fibrillation, renal insufficiency, pulmonary hypertension, obstructive sleep apnea, and other comorbidities. HFpEF has generally been considered a syndrome with high phenotypic heterogeneity, and no effective treatments have been shown to reduce mortality to date. Diuretics and comorbidity management are traditional treatments for HFpEF; however, they are mostly empirical due to a lack of clinical evidence in the setting of HFpEF. With the EMPEROR-Preserved and DELIVER results, sodium-glucose cotransporter 2 inhibitors become the first evidence-based therapies to reduce rehospitalization for heart failure. Subgroup analyses of the PARAGON-HF, TOPCAT, and CHARM-Preserved trials suggest that angiotensin receptor-neprilysin inhibitors, spironolactone, and angiotensin II receptor blockers may be beneficial in patients at the lower end of the ejection fraction spectrum. Other potential pharmacotherapies represented by non-steroidal mineralocorticoid receptor antagonists finerenone and antifibrotic agent pirfenidone also hold promise for the treatment of HFpEF. This article intends to review the clinical evidence on current pharmacotherapies of HFpEF, as well as the comorbidities management of atrial fibrillation, hypertension, T2DM, obesity, pulmonary hypertension, renal insufficiency, obstructive sleep apnea, and iron deficiency, to optimize the clinical management of HFpEF.

Heart Failure with Preserved Ejection Fraction: How to Deal with This Chameleon

Heart failure with preserved ejection fraction (HFpEF) is characterized by a notable heterogeneity in both phenotypic and pathophysiological features, with a growing incidence due to the increase in median age and comorbidities such as obesity, arterial hypertension, and cardiometabolic disease. In recent decades, the development of new pharmacological and non-pharmacological options has significantly impacted outcomes, improving clinical status and reducing mortality. Moreover, a more personalized and accurate therapeutic management has been demonstrated to enhance the quality of life, diminish hospitalizations, and improve overall survival. Therefore, assessing the peculiarities of patients with HFpEF is crucial in order to obtain a better understanding of this disorder. Importantly, comorbidities have been shown to influence symptoms and prognosis, and, consequently, they should be carefully addressed. In this sense, it is mandatory to join forces with a multidisciplinary team in order to achieve high-quality care. However, HFpEF remains largely under-recognized and under-treated in clinical practice, and the diagnostic and therapeutic management of these patients remains challenging. The aim of this paper is to articulate a pragmatic approach for patients with HFpEF focusing on the etiology, diagnosis, and treatment of HFpEF.

Interaction between systemic iron parameters and left ventricular structure and function in the preserved ejection fraction population: a two-sample bidirectional Mendelian randomization study

BACKGROUND

Left ventricular (LV) remodeling and diastolic function in people with heart failure (HF) are correlated with iron status; however, the causality is uncertain. This Mendelian randomization (MR) study investigated the bidirectional causal relationship between systemic iron parameters and LV structure and function in a preserved ejection fraction population.

METHODS

Transferrin saturation (TSAT), total iron binding capacity (TIBC), and serum iron and ferritin levels were extracted as instrumental variables for iron parameters from meta-analyses of public genome-wide association studies. Individuals without myocardial infarction history, HF, or LV ejection fraction (LVEF) < 50% (n = 16,923) in the UK Biobank Cardiovascular Magnetic Resonance Imaging Study constituted the outcome dataset. The dataset included LV end-diastolic volume, LV end-systolic volume, LV mass (LVM), and LVM-to-end-diastolic volume ratio (LVMVR). We used a two-sample bidirectional MR study with inverse variance weighting (IVW) as the primary analysis method and estimation methods using different algorithms to improve the robustness of the results.

RESULTS

In the IVW analysis, one standard deviation (SD) increased in TSAT significantly correlated with decreased LVMVR (β = -0.1365; 95% confidence interval [CI]: -0.2092 to -0.0638; P = 0.0002) after Bonferroni adjustment. Conversely, no significant relationships were observed between other iron and LV parameters. After Bonferroni correction, reverse MR analysis showed that one SD increase in LVEF significantly correlated with decreased TSAT (β = -0.0699; 95% CI: -0.1087 to -0.0311; P = 0.0004). No heterogeneity or pleiotropic effects evidence was observed in the analysis.

CONCLUSIONS

We demonstrated a causal relationship between TSAT and LV remodeling and function in a preserved ejection fraction population.

Anemia and Iron Deficiency Predict All-Cause Mortality in Patients with Heart Failure and Preserved Ejection Fraction: 6-Year Follow-Up Study

AIMS

The aim of this study was to assess the prevalence of anemia and iron deficiency in patients with heart failure with preserved ejection fraction (HFpEF) and its impact on clinical outcomes.

METHODS

We retrospectively analyzed 212 patients with HFpEF and identified anemia as a serum hemoglobin level of less than 13 g/dL in men and less than 12 g/dL in women. Additionally, ID was defined as a serum ferritin concentration < 100 ng/mL or 100-299 ng/mL with transferrin saturation < 20%. Patients were followed up for an average of 66.2 ± 12.1 months, with the endpoint being all-cause mortality among patients with HFpEF, both with and without anemia and iron deficiency. Furthermore, we explored other predictors of all-cause mortality.

RESULTS

The average age of the entire group was 70.6 ± 10.5 years, with females comprising 55% of the patients. Anemia was present in 81 (38.2%) patients, while 108 (50.9%) had iron deficiency. At the end of the follow-up period, 60 (28.3%) of the patients had passed away. Patients with anemia displayed more heart failure (HF) symptoms, diastolic dysfunction, higher NT-pro-BNP levels, and worse baseline functional capacity than those without. Similarly, patients with iron deficiency showed more pronounced HF symptoms and worse functional capacity than those without. The results from the multivariable analyses revealed that anemia (hazard ratio [HR]: 5.401, 95% confidence interval [CI]: 4.303-6.209, log-rank p = 0.001), advanced age, iron deficiency (HR: 3.502, 95% CI: 2.204-6.701, log-rank p = 0.015), decreased left ventricular ejection fraction, chronic kidney disease, and paroxysmal nocturnal dyspnea were all independently associated with all-cause mortality.

CONCLUSIONS

It is essential to consider anemia and iron deficiency as common comorbidities in managing and prognosis HFpEF, as they significantly increase mortality risk.

Safety and Efficacy of Ferric Carboxymaltose in Heart Failure With Preserved Ejection Fraction and Iron Deficiency

Heart Failure with Preserved Ejection Fraction (HFpEF) is a prevalent cardiovascular condition characterized by a complex pathophysiology and limited therapeutic options. Coinciding iron deficiency often compounds the clinical picture, contributing to symptom burden and adverse outcomes. The review underscores the urgency for effective treatments in light of its increasing incidence and considerable healthcare burden. It highlights the clinical significance of addressing iron deficiency in HFpEF patients. FCM emerges as a promising therapeutic modality, demonstrating the ability to rapidly restore iron stores and enhance patients' quality of life while reducing hospitalization rates and mortality. The review thoroughly elucidates the impact of iron deficiency on HFpEF symptoms and outcomes, elucidating how FCM effectively mitigates these challenges. Detailed discussions encompass FCM's mechanism of action, pharmacokinetics, and safety profile. Notably, FCM's adaptability to diverse patient profiles and clinical settings is emphasized, reinforcing its clinical utility. Clinical evidence, including study designs, patient cohorts, and key findings, affirms FCM's potential as a valuable therapeutic option. Real-world data analysis further underscores FCM's practicality and safety beyond controlled clinical trials. The review concludes by addressing future research directions and critical research gaps, accentuating the need for mechanistic insights, long-term outcome studies, and refined patient selection criteria. As FCM increasingly integrates into clinical practice, it offers promise in revolutionizing HFpEF management, addressing an unmet need in this intricate cardiovascular condition.

Modulation of miR-29 influences myocardial compliance likely through coordinated regulation of calcium handling and extracellular matrix

MicroRNAs (miRNAs) control the expression of diverse subsets of target mRNAs, and studies have found miRNA dysregulation in failing hearts. Expression of miR-29 is abundant in heart, increases with aging, and is altered in cardiomyopathies. Prior studies demonstrate that miR-29 reduction via genetic knockout or pharmacologic blockade can blunt cardiac hypertrophy and fibrosis in mice. Surprisingly, this depended on specifically blunting miR-29 actions in cardiomyocytes versus fibroblasts. To begin developing more translationally relevant vectors, we generated a novel transgene-encoded miR-29 inhibitor (TuD-29) that can be incorporated into a viral-mediated gene therapy for cardioprotection. Here, we corroborate that miR-29 expression and activity is higher in cardiomyocytes versus fibroblasts and demonstrate that TuD-29 effectively blunts hypertrophic responses in cultured cardiomyocytes and mouse hearts. Furthermore, we found that adeno-associated virus (AAV)-mediated miR-29 overexpression in mouse hearts induces early diastolic dysfunction, whereas AAV:TuD-29 treatment improves cardiac output by increasing end-diastolic and stroke volumes. The integration of RNA sequencing and miRNA-target interactomes reveals that miR-29 regulates genes involved in calcium handling, cell stress and hypertrophy, metabolism, ion transport, and extracellular matrix remodeling. These investigations support a likely versatile role for miR-29 in influencing myocardial compliance and relaxation, potentially providing a unique therapeutic avenue to improve diastolic function in heart failure patients.

The immunology of heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) now accounts for the majority of new heart failure diagnoses and continues to increase in prevalence in the United States. Importantly, HFpEF is a highly morbid, heterogeneous syndrome lacking effective therapies. Inflammation has emerged as a potential contributor to the pathogenesis of HFpEF. Many of the risk factors for HFpEF are also associated with chronic inflammation, such as obesity, hypertension, aging, and renal dysfunction. A large amount of preclinical evidence suggests that immune cells and their associated cytokines play important roles in mediating fibrosis, oxidative stress, metabolic derangements, and endothelial dysfunction, all potentially important processes in HFpEF. How inflammation contributes to HFpEF pathogenesis, however, remains poorly understood. Recently, a variety of preclinical models have emerged which may yield much needed insights into the causal relationships between risk factors and the development of HFpEF, including the role of specific immune cell subsets or inflammatory pathways. Here, we review evidence in animal models and humans implicating inflammation as a mediator of HFpEF and identify gaps in knowledge requiring further study. As the understanding between inflammation and HFpEF evolves, it is hoped that a better understanding of the mechanisms underlying immune cell activation in HFpEF can open up new therapeutic avenues.

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.

Iron deficiency in heart failure: screening, prevalence, incidence and outcome data from the Swedish Heart Failure Registry and the Stockholm CREAtinine Measurements collaborative project

AIMS

Iron deficiency (ID) is common in heart failure (HF) and linked with poor prognosis regardless of anaemia. We assessed temporal trends in ID testing, ID prevalence, ID incidence, iron need, and outcomes associated with ID in HF across the ejection fraction (EF) spectrum.

METHODS AND RESULTS

From the Swedish HF registry, we enrolled 15 197 patients from Region Stockholm with available EF and collected laboratory tests from routine practice. Iron screening improved since 2016 but remained <25% as of 2018. In 1486 patients with iron biomarkers at baseline, the prevalence of ID was 55% (HF with reduced EF 54%; mildly reduced EF 51%; preserved EF 61%). Iron need was ≥1500 mg in 72% of patients. ID was independently associated with higher risk for HF rehospitalizations (incidence rate ratio [IRR] 1.62, 95% confidence interval [CI] 1.13-2.31) and with cardiovascular (CV) death or repeated HF hospitalizations (IRR 1.63, 95% CI 1.15-2.30) regardless of EF (p-interaction 0.21 and 0.26, respectively), but not with all-cause death, CV death, or first HF hospitalization. Among 96 patients without ID at baseline and with follow-up iron biomarkers, 21% developed ID within 6 months.

CONCLUSIONS

Iron deficiency screening improved over time but is still limitedly implemented, despite being highly prevalent and incident, and independently associated with CV death or HF rehospitalizations regardless of EF. Most patients with ID had an iron need necessitating either repeated administrations of intravenous iron or a preparation permitting >1000 mg doses. These data highlight the need for improved screening for ID in HF.

Treatment of Iron Deficiency in Heart Failure

PURPOSE OF REVIEW

Heart failure (HF) is commonly associated with iron deficiency (ID), defined as insufficient levels of iron to meet physiological demands. ID's association with anaemia is well understood but it is increasingly recognised as an important comorbidity in HF, even in the absence of anaemia. This review summarises contemporary evidence for the measurement and treatment of ID, in both HFrEF and HFpEF, and specific HF aetiologies, and highlights important gaps in the evidence-base.

RECENT FINDINGS

ID is common among patients with HF and associated with increased morbidity and mortality. Correcting ID in patients with HF can impact upon functional status, exercise tolerance, symptoms, and overall quality of life, irrespective of anaemia status. ID is a modifiable comorbidity in HF. Therefore, recognising and treating ID has emerging therapeutic potential and is important for all clinicians who care for patients with HF to understand the rationale and approach to treatment.

Hypophosphataemia risk associated with ferric carboxymaltose in heart failure: A pooled analysis of clinical trials

AIMS

Iron deficiency is a common finding among patients with heart failure (HF) and is associated with adverse outcomes, including decreased quality of life, increased risk of hospitalization, and decreased survival. Intravenous ferric carboxymaltose (FCM) has been shown to improve outcomes among patients with HF and concomitant iron deficiency, but FCM is associated with an increased risk of hypophosphataemia. We aimed to better characterize this risk among HF populations.

METHODS AND RESULTS

This pooled analysis examined data from 41 studies of adults with iron deficiency across disease states and therapeutic areas. Among the 7931 patients treated with FCM available for analysis, 14% made up the HF subgroup. Additional subgroups included women's health (36%), non-dialysis-dependent chronic kidney disease (NDD-CKD; 27%), haemodialysis-dependent chronic kidney disease (HD-CKD; 1%), gastrointestinal (10%), neurology (3%), and other (10%). The incidence of post-baseline moderate or severe hypophosphataemia (i.e. serum phosphate [PO4 3- ] level <2.0 mg/dL) varied across the therapeutic areas, with the lowest incidences observed in the HD-CKD (0%), HF (8.1%), and NDD-CKD (12.8%) subgroups. The prevalence of moderate or severe hypophosphataemia among the women's health, other, gastrointestinal, and neurology subgroups was 30.1%, 40.6%, 51.0%, and 55.6%, respectively. In the HF subgroup, one patient (<0.1%) had a serum PO4 3- of <1.0 mg/dL recorded, compared with 4.8% and 4.0% of the subjects in the neurology and gastrointestinal groups, respectively. With the exception of the HD-CKD subgroup, mean serum PO4 3- levels decreased through weeks 2 to 4, and then returned toward baseline and plateaued by week 8. The strongest predictor of hypophosphataemia was preserved kidney function (estimated glomerular filtration rate: >60 mL/min/1.73 m2 vs. <30 mL/min/1.73 m2 ; odds ratio: 12.2). Among patients in the HF subgroup, the incidence of treatment-emergent adverse events potentially related to hypophosphataemia (e.g. cardiac failure, ventricular tachyarrhythmias, fatigue, muscle weakness, bone pain, neurological symptoms, and muscle pain) was lower among FCM-treated patients than among those receiving placebo, and lower among patients with a post-baseline PO4 3- <2 mg/dL vs. those not meeting such criteria.

CONCLUSIONS

The risk of laboratory-assessed hypophosphataemia in HF patients treated with FCM was lower than that seen in patients in other therapeutic areas treated with FCM, and clinical events associated with hypophosphataemia are uncommon with FCM therapy in this population. Appropriate monitoring, particularly soon after administration in the unlikely event of repeated dosing in HF patients, will allow for further refinement of management strategies. [Correction added on 24 February 2023, after first online publication: In the preceding sentence, "…administration, will allow…" has been corrected to "…administration in the unlikely event of repeated dosing in HF patients, will allow…" in this version.].

Markers of Iron Metabolism and Outcomes in Patients with Heart Failure: A Systematic Review

Iron deficiency (ID) in conjunction with heart failure (HF) poses a challenge for clinicians and is associated with worse HF outcomes. Treatment of ID with IV iron supplementation for patients with HF has demonstrated benefits in quality of life (QoL) and HF-related hospitalizations. The aim of this systematic review was to summarize the evidence linking iron metabolism biomarkers with outcomes in patients with HF to assist in the optimal use of these biomarkers for patient selection. A systematic review of observational studies in English from 2010 to 2022 was conducted using PubMed, with keywords of “Heart Failure” and respective iron metabolism biomarkers (“Ferritin”, “Hepcidin”, “TSAT”, “Serum Iron”, and “Soluble Transferrin Receptor”). Studies pertaining to HF patients, with available quantitative data on serum iron metabolism biomarkers, and report of specific outcomes (mortality, hospitalization rates, functional capacity, QoL, and cardiovascular events) were included, irrespective of left ventricular ejection fraction (LVEF) or other HF characteristics. Clinical trials of iron supplementation and anemia treatment were removed. This systematic review was conducive to formal assessment of risk of bias via Newcastle-Ottawa Scale. Results were synthesized based on their respective adverse outcomes and iron metabolism biomarker(s). Initial and updated searches identified 508 unique titles once duplicates were removed. The final analysis included 26 studies: 58% focused on reduced LVEF; age range was 53–79 years; males composed 41–100% of the reported population. Statistically significant associations of ID were observed with all-cause mortality, HF hospitalization rates, functional capacity, and QoL. Increased risk for cerebrovascular events and acute renal injury have also been reported, but these findings were not consistent. Varying definitions of ID were utilized among the studies; however, most studies employed the current European Society of Cardiology criteria: serum ferritin < 100 ng/mL or the combination of ferritin between 100–299 ng/mL and transferrin saturation (TSAT) < 20%. Despite several iron metabolism biomarkers demonstrating strong association with several outcomes, TSAT better predicted all-cause mortality, as well as long-term risk for HF hospitalizations. Low ferritin was associated with short-term risk for HF hospitalizations, worsening functional capacity, poor QoL, and development of acute renal injury in acute HF. Elevated soluble transferrin receptor (sTfR) levels were associated with worse functional capacity and QoL. Finally, low serum iron was significantly associated with increased risk for cardiovascular events. Considering the lack of consistency among the iron metabolism biomarkers for association with adverse outcomes, it is important to incorporate additional biomarker data, beyond ferritin and TSAT, when assessing for ID in HF patients. These inconsistent associations question how best to define ID to ensure proper treatment. Further research, potentially tailored to specific HF phenotypes, is required to optimize patient selection for iron supplementation therapy and appropriate targets for iron stores replenishment.

What dietary interventions have been tested in heart failure with preserved ejection fraction? A systematic scoping review

AIMS

To determine what dietary interventions have been tested in heart failure with preserved ejection fraction (HFpEF), the modulation method, and outcomes employed and to summarize any evidence for benefit.

METHODS AND RESULTS

We performed key word searches in five bibliographic databases from 2001 to 2021, to identify randomized or experimental dietary interventions tested in HFpEF or mixed heart failure (HF) samples. Study characteristics were summarized according to population, intervention, comparator, outcome categories and intervention complexity was assessed. Twenty-five clinical investigations were retrieved; only 10 (40%) were conducted exclusively in HFpEF; the remainder enrolled mixed HF samples. Most studies employed either highly tailored prescribed diets (n = 12, 48%) or dietary supplementation (n = 10, 40%) modalities. Dietary pattern interventions (n = 3, 12%) are less well represented in the literature.

CONCLUSION

Heterogeneity made pooling studies challenging. Better reporting of baseline characteristics and the use of standardized HF lexicon would ensure greater confidence in interpretation of studies involving mixed HF populations. The field would benefit greatly from explicit reporting of the biological mechanism of action (e.g. the causal pathway) that an intervention is designed to modulate so that studies can be synthesized via their underlying mechanism of action by which diet may affect HF. An extension of the current set of core outcomes proposed by the European Society of Cardiology Heart Failure Association would ensure dietary clinical endpoints are more consistently defined and measured.

REGISTRATION

PROSPERO: CRD42019145388.

Mean corpuscular haemoglobin concentration and outcomes in heart failure with preserved ejection fraction

AIMS

This study aims to evaluate the prognostic value of mean corpuscular haemoglobin concentration (MCHC) on clinical outcomes in patients with heart failure with preserved ejection fraction (HFpEF).

METHODS AND RESULTS

We analysed HFpEF participants from the Americas in the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) trial with available baseline data (n = 1747). Patients were grouped into hypochromia or non-hypochromia group according to a MCHC cut-off level of 330 g/L. Cox proportional hazard model was used to explore the prognostic value of hypochromia on the long-term clinical outcomes (the primary endpoint [composite of cardiovascular mortality, HF hospitalization and aborted cardiac arrest], any-cause and HF hospitalization, all-cause and cardiovascular mortality). Patients were further stratified according to baseline estimated glomerular filtration rate (eGFR) to explore the impact of renal dysfunction on the prognostic value of hypochromia. Baseline hypochromia was prevalent (n = 662, 37.9%) and strongly associated with worse clinical outcomes. In patients with worse renal function (eGFR < 60 mL/min per 1.73 m² ), hypochromia was independently associated with primary endpoint (hazard ratio [HR], 1.56; 95% confidence interval [CI], 1.23-1.98; P < 0.001), any-cause hospitalization (HR, 1.43; 95% CI, 1.20-1.71, P < 0.001) and HF hospitalization (HR, 1.40; 95% CI, 1.07-1.84; P = 0.015), whereas no significant association between hypochromia and these outcomes was found in patients with better renal function.

CONCLUSIONS

Among HFpEF patients, hypochromia (i.e. MCHC ≤ 330 g/L) is independently associated with adverse clinical outcomes, especially when in the presence of co-morbidity renal dysfunction.

Iron deficiency and cardiovascular disease

Iron deficiency (ID) is common in patients with cardiovascular disease. Up to 60% of patients with coronary artery disease, and an even higher proportion of those with heart failure (HF) or pulmonary hypertension have ID; the evidence for cerebrovascular disease, aortic stenosis and atrial fibrillation is less robust. The prevalence of ID increases with the severity of cardiac and renal dysfunction and is probably more common amongst women. Insufficient dietary iron, reduced iron absorption due to increases in hepcidin secondary to the low-grade inflammation associated with atherosclerosis and congestion or reduced gastric acidity, and increased blood loss due to anti-thrombotic therapy or gastro-intestinal or renal disease may all cause ID. For older people in the general population and patients with HF with reduced ejection fraction (HFrEF), both anaemia and ID are associated with a poor prognosis; each may confer independent risk. There is growing evidence that ID is an important therapeutic target for patients with HFrEF, even if they do not have anaemia. Whether this is also true for other HF phenotypes or patients with cardiovascular disease in general is currently unknown. Randomized trials showed that intravenous ferric carboxymaltose improved symptoms, health-related quality of life and exercise capacity and reduced hospitalizations for worsening HF in patients with HFrEF and mildly reduced ejection fraction (<50%). Since ID is easy to treat and is effective for patients with HFrEF, such patients should be investigated for possible ID. This recommendation may extend to other populations in the light of evidence from future trials.

Iron Deficiency and Deranged Myocardial Energetics in Heart Failure

Among different pathomechanisms involved in the development of heart failure, adverse metabolic myocardial remodeling closely related to ineffective energy production, constitutes the fundamental feature of the disease and translates into further progression of both cardiac dysfunction and maladaptations occurring within other organs. Being the component of key enzymatic machineries, iron plays a vital role in energy generation and utilization, hence the interest in whether, by correcting systemic and/or cellular deficiency of this micronutrient, we can influence the energetic efficiency of tissues, including the heart. In this review we summarize current knowledge on disturbed energy metabolism in failing hearts as well as we analyze experimental evidence linking iron deficiency with deranged myocardial energetics.

Effect of Ferric Carboxymaltose Supplementation in Patients with Heart Failure with Preserved Ejection Fraction: Role of Attenuated Oxidative Stress and Improved Endothelial Function

Both clinical and experimental evidence shows that iron deficiency (ID) correlates with an increased incidence of heart failure (HF). Moreover, data on iron supplementation demonstrating a beneficial effect in subjects with HF have mostly been collected in patients undergoing HF with reduced ejection fraction (HFrEF). Relatively poor data, however, exist on the potential of iron supplementation in patients with HF with preserved ejection fraction (HFpEF). Here, we report on data emerging from a multicentric, double-blind, randomized, placebo-controlled study investigating the effect of IV supplementation with a placebo or ferric carboxymaltose (FCM) on 64 subjects with HFpEF. ID was detected by the measurement of ferritin levels. These data were correlated with cardiac performance measurements derived from a 6 min walking test (6MWT) and with echocardiographic determinations of diastolic function. Moreover, an EndoPAT analysis was performed to correlate cardiac functionality with endothelial dysfunction. Finally, the determination of serum malondialdehyde (MDA) was performed to study oxidative stress biomarkers. These measurements were carried out before and 8 weeks after starting treatment with a placebo (100 mL of saline given i.v. in 10 min; n = 32) or FCM at a dose of 500 mg IV infusion (n = 32), which was given at time 0 and repeated after 4 weeks. Our data showed that a condition of ID was more frequently associated with impaired diastolic function, worse 6MWT and endothelial dysfunction, an effect that was accompanied by elevated MDA serum levels. Treatment with FCM, compared to the placebo, improved ferritin levels being associated with an improved 6MWT, enhanced cardiac diastolic function and endothelial reactivity associated with a significant reduction in MDA levels. In conclusion, this study confirmed that ID is a frequent comorbidity in patients with HFpEF and is associated with reduced exercise capacity and oxidative stress-related endothelial dysfunction. Supplementation with FCM determines a significant improvement in diastolic function and the exercise capacity of patients with HFpEF and is associated with an enhanced endothelial function and a reduced production of oxygen radical species.

Why Iron Deficiency in Acute Heart Failure Should Be Treated: A Real-World Clinical Practice Study

Background. This study aims to determine whether the administration of ferric carboxymaltose (FCM) in patients with acute heart failure (AHF) and iron deficiency (ID) improves morbidity and mortality. Methods. We studied 890 consecutive patients admitted for AHF. Patients were divided into six groups according to reduced left ventricular ejection fraction (HFrEF) or preserved (HFpEF), presence of ID, and administration of FCM. Emergency visits, re-admissions, and all-cause mortality were assessed at 6 months. Results. The overall prevalence of ID was 91.2%. In the HFrEF group, no differences were found in isolated events when patients with untreated vs. treated ID were compared, while differences were found in the combined event rate (p = 0.049). The risk calculation showed an absolute risk reduction (ARR) of 10% and relative risk reduction (RRR) of 18%. In HFpEF there was a positive trend with regard to the combined event (p = 0.107), with an ARR of 9% and an RRR of 15%. The number of patients we needed to treat to prevent a combined event was 10.5 in HFrEF and 10.8 in HFpEF. Conclusions. FCM in AHF reduced the combined event rate of emergency visits, re-admission, and all-cause death at 6 months in HF with left ventricular ejection fraction <50%, and showed a positive trend in HFpEF.

SGLT2i in heart failure: can their benefits be expanded across the entire spectrum of ejection fraction?

The publication of the EMPEROR-Preserved trial and data on the benefits of sodium-glucose cotransporter 2 (SGLT2) inhibitors in patients with heart failure (HF) with ejection fraction (EF)> 40% represent a significant step forward in the treatment of HF with preserved EF. Given these results, in February 2022 the US Food and Drug Administration approved the use of empaglifozin in adults with HF with reduced or preserved EF. However, more detailed analysis of the EMPEROR-Preserved trial led to doubts about the effect of empagliflozin in patients with an EF of> 60% this patient group is widely heterogeneous and, probably, a single phenotype cannot be considered in treatment goals or the clinical approach. Moreover, EF occurs on a continuum and classifications of HF according to arbitrary cut-points in EF do not appear consistent with recent evidence, which points to a gradual shift and considerable overlap in underlying mechanisms, phenotypes and treatment response over the spectrum of EF. Enhanced knowledge of pathophysiological mechanisms is essential to establish new therapeutic targets, interpret the results of clinical trials, and develop targeted and effective therapies.

Anemia and iron deficiency in patients with atrial fibrillation

Atrial fibrillation (AF) is the most common cardiac tachyarrhythmia and has a rising global prevalence. Given the increasing burden of AF-related symptoms and complications, new approaches to management are required. Anemia and iron deficiency are common conditions in patients with AF. Furthermore, emerging evidence suggests that the presence of anemia may be associated with worse outcome in these patients. The role of anemia and iron deficiency has been extensively explored in other cardiovascular states, such as heart failure and ischemic heart disease. In particular, the role of iron repletion amongst patients with heart failure is now an established treatment modality. However, despite the strong bidirectional inter-relationship between AF and heart failure, the implications of anemia and iron-deficiency in AF have been scarcely studied. This area is of mechanistic and clinical relevance given the potential that treatment of these conditions may improve symptoms and prognosis in the increasing number of individuals with AF. In this review, we summarise the current published literature on anemia and iron deficiency in patients with AF. We discuss AF complications such as stroke, bleeding, and heart failure, in addition to AF-related symptoms such as exercise intolerance, and the potential impact of anemia and iron deficiency on these. Finally, we summarize current research gaps on anemia, iron deficiency, and AF, and underscore potential research directions.

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.

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.

Iron Deficiency Impacts Diastolic Function, Aerobic Exercise Capacity, and Patient Phenotyping in Heart Failure With Preserved Ejection Fraction: A Subanalysis of the OptimEx-Clin Study

Aims

Iron deficiency (ID) is linked to reduced aerobic exercise capacity and poor prognosis in patients with heart failure (HF) with reduced ejection fraction (HFrEF); however, data for HF with preserved ejection fraction (HFpEF) is scarce. We assessed the relationship between iron status and diastolic dysfunction as well as aerobic exercise capacity in HFpEF, and the contribution of iron status to patient phenotyping.

Methods and Results

Among 180 patients with HFpEF (66% women; median age, 71 years) recruited for the Optimizing Exercise Training in Prevention and Treatment of Diastolic HF (OptimEx-Clin) trial, baseline iron status, including iron, ferritin, and transferrin saturation, was analyzed (n = 169) in addition to exercise capacity (peak oxygen uptake [peak V̇O₂]) and diastolic function (E/e′). ID was present in 60% of patients and was more common in women. In multivariable linear regression models, we found that diastolic function and peak V̇O₂ were independently related to iron parameters; however, these relationships were present only in patients with HFpEF and ID [E/e′ and iron: β−0.19 (95% confidence interval −0.32, −0.07), p = 0.003; E/e′ and transferrin saturation: β−0.16 (−0.28, −0.04), p = 0.011; peak V̇O₂ and iron: β 3.76 (1.08, 6.44), p = 0.007; peak V̇O₂ and transferrin saturation: β 3.58 (0.99, 6.16), p = 0.007]. Applying machine learning, patients were classified into three phenogroups. One phenogroup was predominantly characterized by the female sex and few HFpEF risk factors but a high prevalence of ID (86%, p < 0.001 vs. other phenogroups). When excluding ID from the phenotyping analysis, results were negatively influenced.

Conclusion

Iron parameters are independently associated with impaired diastolic function and low aerobic capacity in patients with HFpEF and ID. Patient phenotyping in HFpEF is influenced by including ID.

Clinical Trial Registration

www.ClinicalTrials.gov, identifier NCT02078947.

Impact of intravenous ferric carboxymaltose on heart failure with preserved and reduced ejection fraction

AIMS

Heart failure (HF) is a proinflammatory disease often associated with the onset of iron deficiency (ID). ID alters mitochondrial function, reducing the generation of cellular energy in skeletal muscle and cardiomyocytes. This study aimed to analyse the response of patients with HF to intravenous iron administration according to the type of HF: preserved ejection fraction (HFpEF) or reduced ejection fraction (HFrEF).

METHODS AND RESULTS

We conducted a retrospective, single-centre study of 565 consecutive outpatients diagnosed with HF, recruited over 5 years, who were given intravenous ferric carboxymaltose (FCM) for the treatment of ID [defined as ferritin < 100 μg/L or ferritin 100-300 μg/L with transferrin saturation (TSAT) < 20%]. Clinical, laboratory, and echocardiographic parameters were analysed before and after administration. After FCM administration, overall ferritin, TSAT, and haemoglobin levels increased up to 5-fold, 1.6-fold, and 1.1-fold, respectively, relative to baseline values in HF patients with reduced and preserved ejection fraction (P < 0.0001), with a greater increase in ferritin and TSAT in HFpEF patients. The left ventricular ejection fraction of the overall series improved by 8 percentage points in both types of HF (from 40% to 48%, P < 0.0001). The percentage of patients with normalization of right ventricular function increased by 6.9 points (from 74.1% to 81%) in HFpEF patients and by 6.4 points (from 53% to 59.4%) in the HFrEF subgroup (P < 0.0001). New York Heart Association functional status slightly improved, from a median of 2.4 (interquartile range, IQR: 2-2.7) to 1.9 (IQR: 1.5-2.5; P < 0.0001) after FCM in both types of HF. No changes were noted in plasma levels of liver enzymes, creatinine, or natriuretic peptide (P > 0.05).

CONCLUSIONS

Intravenous iron administration appeared to improve ejection fraction and cardiac functional status in outpatients with ID and HF with both preserved and reduced ejection fraction.

Impact of change in iron status over time on clinical outcomes in heart failure according to ejection fraction phenotype

Aims

The importance of iron deficiency (ID) in heart failure with preserved ejection fraction (HFpEF) is unknown. In HF with reduced ejection fraction (HFrEF), ID is reported as an independent predictor of mortality in HF although not all published studies agree. Different definitions of ID have been assessed, and the natural history of untreated ID not established, which may explain the conflicting results. This study aimed to assess the relationship between ID and mortality in HFpEF, clarify which definition of ID correlates best with outcomes in HFrEF, and determine the prognostic importance of change in ID status over time.

Methods and results

Analyses were conducted on data from 1563 patients participating in a prospective international cohort study comparing HFpEF with HFrEF. Plasma samples from baseline and 6 month visits were analysed for the presence of ID. Two ID definitions were evaluated: ID_Ferritin = ‘ferritin < 100 mcg/L or ferritin 100–300 mcg/L + transferrin saturation < 20%’ and ID_Tsat = ‘transferrin saturation < 20%’. The risk of all‐cause mortality and death/HF hospitalization associated with baseline ID (ID_Ferritin or ID_Tsat) and change in ID status at 6 months (persistent, resolving, developing, or never present) was estimated in multivariable Cox proportional hazards models. Of 1563 patients, 1115 (71%) had HFrEF and 448 (29%) HFpEF. Prevalence of ID was similar in HFpEF and HFrEF (58%). Patients with ID were more likely to be female, diabetic, and have a higher co‐morbid burden than patients without ID. ID by either definition did not confer independent risk for either all‐cause mortality or death/HF hospitalization for patients with HFpEF [ID_Ferritin hazard ratio (HR) 0.65 (95% confidence interval 0.40–1.05), P = 0.08; ID_Tsat HR 1.16 (0.72–1.87), P = 0.55]. In the overall study cohort (HFrEF + HFpEF) and HFrEF subgroup, ID_Ferritin was inferior to ID_Tsat in prediction of all‐cause mortality [overall cohort: HR 1.21 (0.95–1.53), P = 0.12 vs. HR 1.95 (1.52–2.51), P < 0.01; HFrEF: HR 1.12 (0.85–1.48), P = 0.43 vs. HR 1.57 (1.15–2.14), P < 0.01]. Persistence of ID_Tsat at 6 months was strongly associated with poor outcomes compared with never having ID_Tsat [HR 2.22 (1.42–3.46), P < 0.01] or having ID_Tsat at baseline self‐resolve by 6 months [HR 1.40 (1.06–1.86), P = 0.02].

Conclusions

Iron deficiency is equally prevalent in HFpEF and HFrEF but is negatively prognostic only in HFrEF. The natural history of ID is important; persistent ID is strongly associated with mortality whereas resolution is not. ID_Tsat is the superior definition of ID and should inform future trials investigating the efficacy of intravenous iron replacement in patients with HFrEF.

Could a Multi-Marker and Machine Learning Approach Help Stratify Patients with Heart Failure?

Half of the patients with heart failure (HF) have preserved ejection fraction (HFpEF). To date, there are no specific markers to distinguish this subgroup. The main objective of this work was to stratify HF patients using current biochemical markers coupled with clinical data. The cohort study included HFpEF (n = 24) and heart failure with reduced ejection fraction (HFrEF) (n = 34) patients as usually considered in clinical practice based on cardiac imaging (EF ≥ 50% for HFpEF; EF < 50% for HFrEF). Routine blood tests consisted of measuring biomarkers of renal and heart functions, inflammation, and iron metabolism. A multi-test approach and analysis of peripheral blood samples aimed to establish a computerized Machine Learning strategy to provide a blood signature to distinguish HFpEF and HFrEF. Based on logistic regression, demographic characteristics and clinical biomarkers showed no statistical significance to differentiate the HFpEF and HFrEF patient subgroups. Hence a multivariate factorial discriminant analysis, performed blindly using the data set, allowed us to stratify the two HF groups. Consequently, a Machine Learning (ML) strategy was developed using the same variables in a genetic algorithm approach. ML provided very encouraging explorative results when considering the small size of the samples applied. The accuracy and the sensitivity were high for both validation and test groups (69% and 100%, 64% and 75%, respectively). Sensitivity was 100% for the validation and 75% for the test group, whereas specificity was 44% and 55% for the validation and test groups because of the small number of samples. Lastly, the precision was acceptable, with 58% in the validation and 60% in the test group. Combining biochemical and clinical markers is an excellent entry to develop a computer classification tool to diagnose HFpEF. This translational approach is a springboard for improving new personalized treatment methods and identifying “high-yield” populations for clinical trials.

Iron therapy in iron-deficiency patients with heart failure with preserved ejection fraction: A protocol for meta-analysis

BACKGROUND

Nearly half of patients with heart failure (HF) have preserved ejection fraction (EF) and the mortality and morbidity of patients with HF with preserved EF (HFpEF) are high. However, there is no established therapy to improve survival in these patients. HFpEF patients are often elderly and their primary chronic symptom is severe exercise intolerance. Thus, improvement of exercise capacity presents another important clinical outcome in HFpEF patients. Iron deficiency is common in HF patients, and the presence of iron deficiency, regardless of concomitant anemia, is associated with worse symptoms, impaired exercise capacity, and higher mortality and hospitalization in these patients. Several meta-analyses of randomized controlled trials reported that iron administration improved HF symptoms, exercise capacity, and clinical outcomes in iron-deficiency patients with HF with reduced EF. However, there is insufficient evidence as to the effect of iron administration in iron-deficiency HFpEF patients.

METHODS AND RESULTS

This meta-analysis will include randomized controlled trials on the effects of iron administration on HF symptoms, exercise capacity, and health-related quality of life in iron-deficiency HFpEF patients. Information of studies will be collected from PubMed, Web of Science, Cochrane Library, and ClinicalTrials.gov. The primary outcome will be exercise capacity (6-minute walking distance). The secondary outcomes will be HF symptoms, health-related quality of life, and mortality and hospitalization rates.

CONCLUSION

This meta-analysis will evaluate the effect of iron therapy in iron-deficiency HFpEF patients, providing evidence as to the iron administration in these patients.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020205297.

Interleukin 6 and Development of Heart Failure With Preserved Ejection Fraction in the General Population

Background The cause of heart failure with preserved ejection fraction (HFpEF) is poorly understood, and specific therapies are lacking. Previous studies suggested that inflammation plays a role in the development of HFpEF. Herein, we aimed to investigate in community-dwelling individuals whether a higher plasma interleukin 6 (IL-6) level is associated with an increased risk of developing new-onset heart failure (HF) over time, and specifically HFpEF. Methods and Results We performed a case-cohort study based on the PREVEND (Prevention of Renal and Vascular End-Stage Disease) study, a prospective general population-based cohort study. We included 961 participants, comprising 200 participants who developed HF and a random group of 761 controls. HF with reduced ejection fraction or HFpEF was defined on the basis of the left ventricular ejection fraction of ≤40% or >40%, respectively. In Cox proportional hazard regression analyses, IL-6 levels were statistically significantly associated with the development of HF (hazard ratio [HR], 1.28; 95% CI, 1.02-1.61; P=0.03) after adjustment for key risk factors. Specifically, IL-6 levels were significantly associated with the development of HFpEF (HR, 1.59; 95% CI, 1.16-2.19; P=0.004), whereas the association with HF with reduced ejection fraction was nonsignificant (HR, 1.05; 95% CI, 0.75-1.47; P=0.77). In sensitivity analyses, defining HFpEF as left ventricular ejection fraction ≥50%, IL-6 levels were also significantly associated with the development of HFpEF (HR, 1.47; 95% CI, 1.04-2.06; P=0.03) after adjustment for key risk factors. Conclusions IL-6 is associated with new-onset HFpEF in community-dwelling individuals, independent of potential confounders. Our findings warrant further research to investigate whether IL-6 might be a novel treatment target to prevent HFpEF.

The Prognostic Significance of Anemia in Patients With Heart Failure: A Meta-Analysis of Studies From the Last Decade

Background: Anemia is a commonly occurring comorbidity in patients with heart failure (HF). Although there are a few reports of a higher prevalence of mortality and hospitalization-related outcomes due to accompanying anemia, other studies suggest that anemia does not have an adverse impact on the prognostic outcomes of HF. Two meta-analyses in the past decade had reported the adverse impact of anemia on both mortality and hospitalization- related outcomes. However, only one of these studies had evaluated the outcome while using multivariable adjusted hazard ratios. Moreover, several studies since then reported the prognostic influence of anemia in HF. In this present study, we evaluate the prognostic impact of anemia on mortality and hospitalization outcomes in patients with HF.

Methods: We carried out a systematic search of the academic literature in the scientific databases EMBASE, CENTRAL, Scopus, PubMed, Cochrane, ISI Web of Science, clinicaltrial.gov, and MEDLINE based on the PRISMA guidelines. Meta-analysis was then performed to evaluate the effect (presented as risk ratio) of anemia on the overall mortality and hospitalization outcome in patients with HF.

Results: Out of 1,397 studies, 11 eligible studies were included with a total of 53,502 (20,615 Female, 32,887 Male) HF patients (mean age: 71.6 ± 8.3-years, Hemoglobin: 11.9 ± 1.5 g/dL). Among them, 19,794 patients suffered from anemia (Hb: 10.5 ± 1.6), and 33,708 patients did not have anemia (Hb: 13.2 ± 1.7 g/dL). A meta-analysis revealed a high-odds ratio (OR) for the overall mortality in patients with anemia (OR: 1.43, 95% CI: 1.29–1.84). A high-risk ratio was also reported for hospitalization as the outcome in patients with anemia (1.22, 1.0–1.58).

Conclusion: This systematic review and meta-analysis provide evidence of the high risk of mortality and hospitalization-related outcomes in patients with HF and anemia. The study confirms the findings of previously published meta-analyses suggesting anemia as an important and independent risk factor delineating the prognostic outcome of chronic HF.

Iron deficiency in heart failure

Iron deficiency is a major heart failure co‐morbidity present in about 50% of patients with stable heart failure irrespective of the left ventricular function. Along with compromise of daily activities, it also increases patient morbidity and mortality, which is independent of anaemia. Several trials have established parenteral iron supplementation as an important complimentary therapy to improve patient well‐being and physical performance. Intravenous iron preparations, in the first‐line ferric carboxymaltose, demonstrated in previous clinical trials superior clinical effect in comparison with oral iron preparations, improving New York Heart Association functional class, 6 min walk test distance, peak oxygen consumption, and quality of life in patients with chronic heart failure. Beneficial effect of iron deficiency treatment on morbidity and mortality of heart failure patients is waiting for conformation in ongoing trials. Although the current guidelines for treatment of chronic and acute heart failure acknowledge importance of iron deficiency correction and recommend intravenous iron supplementation for its treatment, iron deficiency remains frequently undertreated and insufficiently diagnosed in setting of the chronic heart failure. This paper highlights the current state of the art in the pathophysiology of iron deficiency, associations with heart failure trajectory and outcome, and an overview of current guideline‐suggested treatment options.

Iron deficiency impacts prognosis but less exercise capacity in heart failure with preserved ejection fraction

AIMS

Whether and how iron deficiency (ID) impacts patients with heart failure (HF) with preserved ejection fraction (HFpEF) remain unclear. The aim of our study was to investigate the impact of ID on functional status, exercise capacity, and prognosis in HFpEF.

METHODS AND RESULTS

The study population consisted of 300 HFpEF patients. ID was defined as serum ferritin <100 μg/L or 100-300 μg/L and transferrin-saturation <20%. Baseline functional status, quality of life (HADS score and EQ 5D index), 6 min walking test, echocardiography, and outcome (all-cause mortality and combined all cause-mortality and HF hospitalization) were evaluated. ID was found in 159 (53%) patients. Patients with ID had a worse prognosis with a higher combined endpoint of all-cause mortality and HF hospitalization after 4 years of follow-up (log rank = 0.008). Pulmonary hypertension, depression, and thyroid disease were more prevalent in the ID group. Multivariable analysis showed that ID was independently associated with body mass index (P = 0.003), pulmonary hypertension (P = 0.008), and thyroid disease (P = 0.01). Although patients with ID had a lower exercise capacity compared with patients without ID (393 m [294-455] vs. 344 m [260-441], P = 0.008), there was no significant correlation after multivariable correction for age, BMI, NT-proBNP, DM, and depression.

CONCLUSIONS

Heart failure with preserved ejection fraction patients with ID have a worse prognosis and impaired exercise capacity compared with those without ID. However, although a trend was observed, after multivariable correction ID was no longer significantly associated with a reduced exercise capacity. This reflects that impaired exercise capacity in HFpEF is complex and seems multifactorial. Interestingly, pulmonary hypertension was an independent predictor of both ID and exercise capacity.

How I treat anemia in heart failure

Anemia is a very common comorbidity in patients with heart failure (HF), affecting ∼30% of stable ambulatory patients and 50% patients with acute decompensated HF. Absolute or functional iron deficiency (ID) is seen in ∼50% patients with HF. Both of these comorbidities often coexist and are independently associated with increased mortality and hospitalizations. These findings led several investigators to test the hypotheses that treatment of anemia and ID in HF would improve symptoms and long-term outcomes. Small studies showed that erythropoiesis-stimulating agents (ESAs) improve subjective measures of HF. However, a large pivotal outcome trial found that the ESA darbepoetin alfa did not improve long-term outcomes in patients with HF with reduced ejection fraction and instead was associated with adverse effects. Studies using IV iron have had somewhat greater success, showing improvements in subjective and some objective measures of HF. However, more research is needed to establish the best treatment options for these high-risk patients. We present 5 common scenarios of patients with HF and anemia and describe our personal approach on how we might treat them based on objective evidence where available. An algorithm that offers guidance in regard to personalized therapy for such patients is also presented.

Diagnosis and Treatment of Iron Deficiency in Heart Failure: OFICSel study by the French Heart Failure Working Group

AIMS

Iron deficiency (ID) occurs in about 50% of patients with heart failure (HF). The European Society of Cardiology (ESC) recommends ID diagnostic testing in newly diagnosed patients with HF and during follow-up, with intravenous iron supplementation (IS) only recommended in patients with HF with reduced ejection fraction (HFrEF). This study aimed to assess prevalence, clinical characteristics, and application of ESC guidelines for ID and IS in patients with HF in the real-life clinical setting.

METHODS AND RESULTS

The French transversal multicentre OFICSel registry (300 cardiologists) conducted in 2017 included patients hospitalized for HF at least once in the previous 5 years. Diverse adult patients were eligible including inpatients and outpatients and those with acute and chronic HF. Data were collected from cardiologists and patients using study-specific surveys. Data included demographic and clinical data, as well as HF and ID management data. Overall, 2822 patients, mainly male (69.3%) with a median age of 69 years (interquartile range 58-78), were included. A total of 1075 patients (38.1%) were tested for ID, with 364 (33.9%) diagnosed. Of these, 168 (46.2%) received IS: 128 (76.2%) intravenous IS and 40 (23.8%) oral. Among the 201 patients with HFrEF diagnosed with ID, 99 (49.3%) received IS: 79 (79.8%) intravenous IS and 20 (20.2%) oral.

CONCLUSIONS

In clinical practice, only one-third of patients with HF had a diagnostic test for ID. In patients with ID with HFrEF, only 39.3% received intravenous IS as recommended. Thus, in general, cardiologists should be encouraged to follow the ESC guidelines to ensure optimal treatment for patients with HF.

Evaluation of the prescribing practice of guideline-directed medical therapy among ambulatory chronic heart failure patients

BACKGROUND

Studies have demonstrated that heart failure (HF) patients who receive direct pharmacist input as part of multidisciplinary care have better clinical outcomes. This study evaluated/compared the difference in prescribing practices of guideline-directed medical therapy (GDMT) for chronic HF patients between two multidisciplinary clinics-with and without the direct involvement of a pharmacist.

METHODS

A retrospective audit of chronic HF patients, presenting to two multidisciplinary outpatient clinics between March 2005 and January 2017, was performed; a Multidisciplinary Ambulatory Consulting Service (MACS) with an integrated pharmacist model of care and a General Cardiology Heart Failure Service (GCHFS) clinic, without the active involvement of a pharmacist.

RESULTS

MACS clinic patients were significantly older (80 vs. 73 years, p < .001), more likely to be female (p < .001), and had significantly higher systolic (123 vs. 112 mmHg, p < .001) and diastolic (67 vs. 60 mmHg, p < .05) blood pressures compared to the GCHF clinic patients. Moreover, the MACS clinic patients showed more polypharmacy and higher prevalence of multiple comorbidities. Both clinics had similar prescribing rates of GDMT and achieved maximal tolerated doses of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) in HFrEF. However, HFpEF patients in the MACS clinic were significantly more likely to be prescribed ACEIs/ARBs (70.5% vs. 56.2%, p = 0.0314) than the GCHFS patients. Patients with both HFrEF and HFpEF (MACS clinic) were significantly less likely to be prescribed β-blockers and mineralocorticoid receptor antagonists. Use of digoxin in chronic atrial fibrillation (AF) in MACS clinic was significantly higher in HFrEF patients (82.5% vs. 58.5%, p = 0.004), but the number of people anticoagulated in presence of AF (27.1% vs. 48.0%, p = 0.002) and prescribed diuretics (84.0% vs. 94.5%, p = 0.022) were significantly lower in HFpEF patients attending the MACS clinic. Age, heart rate, systolic blood pressure (SBP), anemia, chronic renal failure, and other comorbidities were the main significant predictors of utilization of GDMT in a multivariate binary logistic regression.

CONCLUSIONS

Lower prescription rates of some medications in the pharmacist-involved multidisciplinary team were found. Careful consideration of demographic and clinical characteristics, contraindications for use of medications, polypharmacy, and underlying comorbidities is necessary to achieve best practice.

Iron deficiency and safety of ferric carboxymaltose in patients with acute heart failure. AHF-ID study

INTRODUCTION

The presence of iron deficiency (ID) in patients with acute heart failure (AHF) is high. There are few studies on the characteristics of these patients and the safety of ferric carboxymaltose administration (FCM).

OBJECTIVE

Study the differences among patients with AHF based on the presence and type of ID as well as the safety of FCM administration in these patients.

METHOD

The AHF-ID study is a multicentre, analytical, prospective follow-up cohort including patients admitted to six Spanish hospitals for AHF. ID was defined as serum ferritin <100 μg/L (group A) or ferritin 100-299 μg/L with a TSAT <20% (group B). In cases receiving FCM the appearance of adverse events was analysed. Adjusted Cox regression was used to determine the association with 30-days reattendance for AHF after discharge.

RESULTS

A total of 221 patients were recruited; 191 (86.4%) presented ID, 121 (63.4%) group A and 70 (36.6%) group B. There were scarce differences between the groups analysed. No differences were found in 30-days reattendance for AHF. FCM was administered to 158 (71.5%) patients, with 8 (5.1%) presenting adverse events, the most frequent being digestive alterations. Treatment was not discontinued in any case.

CONCLUSIONS

There are scarce differences between the presence and the type of ID in patients with AHF. The administration of FCM in patients with ID and AHF is safe.

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.