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

Anemia: A Connection Between Heart Failure and Kidney Failure

Erythropoiesis-stimulating agents (ESAs) have improved the quality of life and reduced the need for transfusions in patients with chronic kidney disease. However, randomized trials showed no benefit but possible safety issues following high doses of ESAs given to reach normal hemoglobin levels. Iron therapy is used together with ESA; when given proactively, it may reduce the risk of mortality and cardiovascular events in hemodialysis patients. Recent trials also showed benefits of intravenous iron therapy in patients with heart failure. New drugs for correcting anemia may retain the present efficacy of ESAs as antianemic drugs and reduce cardiovascular risks.

Intravenous iron for heart failure with evidence of iron deficiency: a meta-analysis of randomised trials

BACKGROUND

The recent AFFIRM-AHF trial assessing the effect of intravenous (IV) iron on outcomes in patients hospitalised with worsening heart failure who had iron deficiency (ID) narrowly missed its primary efficacy endpoint of recurrent hospitalisations for heart failure (HHF) or cardiovascular (CV) death. We conducted a meta-analysis to determine whether these results were consistent with previous trials.

METHODS

We searched for randomised trials of patients with heart failure investigating the effect of IV iron vs placebo/control groups that reported HHF and CV mortality from 1st January 2000 to 5th December 2020. Seven trials were identified and included in this analysis. A fixed effect model was applied to assess the effects of IV iron on the composite of first HHF or CV mortality and individual components of these.

RESULTS

Altogether, 2,166 patients were included (n = 1168 assigned to IV iron; n = 998 assigned to control). IV iron reduced the composite of HHF or CV mortality substantially [OR 0.73; (95% confidence interval 0.59-0.90); p = 0.003]. Outcomes were consistent for the pooled trials prior to AFFIRM-AHF. Whereas first HHF were reduced substantially [OR 0.67; (0.54-0.85); p = 0.0007], the effect on CV mortality was uncertain but appeared smaller [OR 0.89; (0.66-1.21); p = 0.47].

CONCLUSION

Administration of IV iron to patients with heart failure and ID reduces the risk of the composite outcome of first heart failure hospitalisation or cardiovascular mortality, but this outcome may be driven predominantly by an effect on HHF. At least three more substantial trials of intravenous iron are underway.

Iron status, fibroblast growth factor 23 and cardiovascular and kidney outcomes in chronic kidney disease

Disordered iron and mineral homeostasis are interrelated complications of chronic kidney disease that may influence cardiovascular and kidney outcomes. In a prospective analysis of 3747 participants in the Chronic Renal Insufficiency Cohort Study, we investigated risks of mortality, heart failure, end-stage kidney disease (ESKD), and atherosclerotic cardiovascular disease according to iron status, and tested for mediation by C-terminal fibroblast growth factor 23 (FGF23), hemoglobin and parathyroid hormone. Study participants were agnostically categorized based on quartiles of transferrin saturation and ferritin as: "Iron Replete" (27.1% of participants; referent group for all outcomes analyses), "Iron Deficiency" (11.1%), "Functional Iron Deficiency" (7.6%), "Mixed Iron Deficiency" (iron indices between the Iron Deficiency and Functional Iron Deficiency groups; 6.3%), "High Iron" (9.2%), or "Non-Classified" (the remaining 38.8% of participants). In multivariable-adjusted Cox models, Iron Deficiency independently associated with mortality (hazard ratio 1.28, 95% confidence interval 1.04-1.58) and heart failure (1.34, 1.05- 1.72). Mixed Iron Deficiency associated with mortality (1.61, 1.27-2.04) and ESKD (1.33, 1.02-1.73). High Iron associated with mortality (1.54, 1.24-1.91), heart failure (1.58, 1.21-2.05), and ESKD (1.41, 1.13-1.77). Functional Iron Deficiency did not significantly associate with any outcome, and no iron group significantly associated with atherosclerotic cardiovascular disease. Among the candidate facilitators, FGF23 most significantly mediated the risks of mortality and heart failure conferred by Iron Deficiency. Thus, alterations in iron homeostasis associated with adverse cardiovascular and kidney outcomes in patients with chronic kidney disease.

Anaemia in Heart Failure Patients, Associated with Angiotensin - Renin - Aldosterone System Altering Medications

Heart failure (HF) remains one of the most common diseases and one of the major causes of death worldwide. HF is often associated with other chronic diseases, most commonly with anemia. Anemia increases patients' mortality and lowers their quality of life. There are a few pathophysiological mechanisms that explain anemia in patients with HF - hemodilution, absolute or functional iron deficiency, activation of the inflammatory cascade, chronic kidney disease, and impaired erythropoietin production and activity. Moreover, congestive HF is often treated with angiotensin-converting enzyme inhibitors and aldosterone receptors blockers, which could be linked to the development of anemia.

Intravenous iron in heart failure and chronic kidney disease

Intravenous iron therapy is increasingly being used worldwide to treat anemia in chronic kidney disease and more recently iron deficiency in heart failure. Promising results were obtained in randomized clinical trials in the latter, showing symptomatic and functional capacity improvement with intravenous iron therapy. Meanwhile, confirmation of clinical benefit in hard-endpoints such as mortality and hospitalization is expected in large clinical trials that are already taking place. In chronic kidney disease, concern about iron overload is being substituted by claims of direct cardiovascular benefit of iron supplementation, as suggested by preliminary studies in heart failure. We discuss the pitfalls of present studies and gaps in knowledge, stressing the known differences between iron metabolism in heart and renal failure. Systemic and cellular iron handling and the role of hepcidin are reviewed, as well as the role of iron in atherosclerosis, especially in view of its relevance to patients undergoing dialysis. We summarize the evidence available concerning iron overload, availability and toxicity in CKD, that should be taken into account before embracing aggressive intravenous iron supplementation.

Exercise Dynamic of Patients with Chronic Heart Failure and Reduced Ejection Fraction

PURPOSE OF REVIEW

Exercise causes various dynamic changes in all body parts either in healthy subject or in heart failure (HF) patients. The present review of current knowledge about HF patients with reduced ejection fraction focuses on dynamic changes along a "metabo-hemodynamic" perspective.

RECENT FINDINGS

Studies on the dynamic changes occurring during exercise span many years. Thanks to the availability of advanced methods, it is nowadays possible to properly characterize respiratory, hemodynamic, and muscular function adjustments and their mismatch with the pulmonary and systemic circulations. Exercise is a dynamic event that involves several body functions. In HF patients, it is important to know at what level the limitation takes place in order to better manage these patients and to optimize therapeutic strategies.

Systemic iron deficiency does not affect the cardiac iron content and progression of heart failure

Chronic heart failure (HF) is often accompanied by systemic iron deficiency (ID). However, effects of ID on cardiac iron status and progression of HF are unknown. To investigate these effects rats underwent LAD ligation to induce post-myocardial infarction HF or sham operation. After 3 weeks the animals from both groups were randomized into three subgroups: control, moderate ID and severe ID+anemia (IDA) by a combination of phlebotomy and low iron diet for 5 weeks. Serum and hepatic iron content were reduced by 55% and 70% (ID) and by 80% and 77% (IDA), respectively, while cardiac iron content was unchanged in HF rats. Changes in expression of all cardiomyocyte iron handling proteins indicating preserved cardiomyocytes iron status in HF and ID/IDA. Contractile function of LV cardiomyocytes, Ca²⁺ transient amplitude, sarcoplasmic reticulum Ca²⁺ release and SERCA2a function was augmented by ID and IDA and it was accompanied by an increase in serum catecholamines. Neither ID nor IDA affected left ventricular (LV) systolic or diastolic function or dimensions. To sum up, systemic ID does not result in cardiac ID and does not affect progression of HF and even improves contractile function and Ca²⁺ handling of isolated LV cardiomyocytes, however, at the cost of increased catecholamine level. This suggests that intravenous iron therapy should be considered as an additional therapeutic option in HF, preventing the increase of catecholaminergic drive with its well-known long-term adverse effects.

Supplementation with Iron in Pulmonary Arterial Hypertension. Two Randomized Crossover Trials

Rationale: Iron deficiency, in the absence of anemia, is common in patients with idiopathic and heritable pulmonary arterial hypertension (PAH) and is associated with a worse clinical outcome. Oral iron absorption may be impeded by elevated circulating hepcidin concentrations. The safety and benefit of parenteral iron replacement in this patient population is unclear. Objectives: To evaluate the safety and efficacy of parenteral iron replacement in PAH. Methods: In two randomized, double-blind, placebo-controlled 12-week crossover studies, 39 patients in Europe received a single infusion of ferric carboxymaltose (Ferinject) (1,000 mg or 15 mg/kg if weight <66.7 kg) or saline as placebo, and 17 patients in China received iron dextran (Cosmofer) (20 mg iron/kg body weight) or saline placebo. All patients had idiopathic or heritable PAH and iron deficiency at entry as defined by a serum ferritin <37 μg/L or iron <10.3 μmol/L or transferrin saturations <16.4%. Results: Both iron treatments were well tolerated and improved iron status. Analyzed separately and combined, there was no effect on any measure of exercise capacity (using cardiopulmonary exercise testing or 6-minute walk test) or cardiopulmonary hemodynamics, as assessed by right heart catheterization, cardiac magnetic resonance, or plasma NT-proBNP (N-terminal-pro hormone brain natriuretic peptide) at 12 weeks. Conclusions: Iron repletion by administration of a slow-release iron preparation as a single infusion to patients with PAH with iron deficiency without overt anemia was well tolerated but provided no significant clinical benefit at 12 weeks. Clinical trial registered with ClinicalTrials.gov (NCT01447628).

Natural history and prognostic significance of iron deficiency and anaemia in ambulatory patients with chronic heart failure

AIMS

Iron deficiency (ID) and anaemia are common in heart failure; less is known about changes over time.

METHODS AND RESULTS

We investigated prevalence, incidence and resolution of ID and anaemia in 906 patients with chronic heart failure (median age 73 (65-79) years, 70% men, 51% with heart failure with reduced ejection fraction) 1 year apart. ID was defined as serum iron ≤13 µmol/L and anaemia as haemoglobin <13.0 g/dL for men or <12.0 g/dL for women. FAIR-HF criteria for ID were also considered. At baseline, 10% had anaemia without ID, 23% had ID without anaemia, 20% had both, and 47% had neither. Percentages changed little over 1 year, but 157 (30%) patients had new-onset ID, 104 (16%) new-onset anaemia, whilst ID resolved in 173 (44%) and anaemia in 63 (23%). Compared to those who remained iron replete (iron >13 µmol/L), mortality was higher in those with persistent or incident ID at 1 year [hazard ratio (HR) 1.81 (1.23-2.67), and HR 1.40 (0.91-2.14), respectively] in multivariable models (P = 0.02). Compared to persistent ID, resolution of ID was associated with a lower mortality [HR 0.61 (0.44-0.86); P = 0.004]. Changes in ID defined by FAIR-HF criteria were not similarly associated with mortality. Anaemia was associated with a poor outcome even if it resolved.

CONCLUSIONS

The prevalence and incidence of ID and anaemia are high in chronic heart failure but so is the rate of resolution. Persistent or incident ID, defined by a serum iron ≤13 µmol/L, is associated with higher mortality and resolution of ID with lower mortality.

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.

Heart Failure Hospitalization Risk associated with Iron Status in Veterans with CKD

BACKGROUND AND OBJECTIVES

CKD is an independent risk factor for heart failure. Iron dysmetabolism potentially contributes to heart failure, but this relationship has not been well characterized in CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We performed a historical cohort study using data from the Veterans Affairs Corporate Data Warehouse to evaluate the relationship between iron status and heart failure hospitalization. We identified a CKD cohort with at least one set of iron indices between 2006 and 2015. The first available date of serum iron indices was identified as the study index date. The cohort was divided into four iron groups on the basis of the joint quartiles of serum transferrin saturation (shown in percent) and ferritin (shown in nanograms per milliliter): reference (16%-28%, 55-205 ng/ml), low iron (0.4%-16%, 0.9-55 ng/ml), high iron (28%-99.5%, 205-4941 ng/ml), and function iron deficiency (0.8%-16%, 109-2783 ng/ml). We compared 1-year heart failure hospitalization risk between the iron groups using matching weights derived from multinomial propensity score models and Poisson rate-based regression.

RESULTS

A total of 78,551 veterans met the eligibility criteria. The covariates were well balanced among the iron groups after applying the propensity score weights (n=31,819). One-year adjusted relative rate for heart failure hospitalization in the iron deficiency groups were higher compared with the reference group (low iron: 1.29 [95% confidence interval, 1.19 to 1.41]; functional iron deficiency: 1.25 [95% confidence interval, 1.13 to 1.37]). The high-iron group was associated with lower 1-year relative rate of heart failure hospitalization (0.82; 95% confidence interval, 0.72 to 0.92). Furthermore, the association between iron deficiency and heart failure hospitalization risk remained consistent regardless of the diabetes status or heart failure history at baseline.

CONCLUSIONS

Iron deficiency, regardless of cause, was associated with higher heart failure hospitalization risk in CKD. Higher iron status was associated with lower heart failure hospitalization risks.

Anemia of cardiorenal syndrome

Cardiorenal syndrome includes a spectrum of disorders of the kidneys and heart in which loss of function in one organ contributes to reduced function in the other organ. Cardiorenal syndrome is frequently complicated by comorbid anemia, which leads to reciprocal and progressive cardiac and renal deterioration. The triad of heart failure, chronic kidney disease (CKD), and anemia is termed cardiorenal anemia syndrome (CRAS). There are currently no evidence-based recommendations for managing patients with CRAS; however, the treatment of these patients is multifactorial. Not only must the anemia be controlled, but heart failure and kidney injury must be addressed, in addition to other comorbidities. Intravenous iron and erythropoiesis-stimulating agents are the mainstays of treatment for anemia of CKD, addressing both iron and erythropoiesis deficiencies. Since erythropoiesis-stimulating agent therapy can be associated with adverse outcomes at higher doses in patients with CKD and is not used in routine practice in patients with heart failure, treatment options for managing anemia in patients with CRAS are limited. Several new therapies, particularly the hypoxia-inducible factor-prolyl hydroxylase inhibitors, are currently under clinical development. The hypoxia-inducible factor-prolyl hydroxylase inhibitors have shown promising results for treating anemia of CKD in clinical trials and may confer benefits in patients with CRAS, potentially addressing some of the limitations of erythropoiesis-stimulating agents. Updated clinical practice guidelines for the screening and management of anemia in cardiorenal syndrome, in light of potential new therapies and clinical evidence, would improve the clinical outcomes of patients with this complex syndrome.

Iron deficiency in pulmonary arterial hypertension: prevalence and potential usefulness of oral supplementation

BACKGROUND

The aim of this study was to evaluate the prevalence of iron depletion in a prevalent population of patients with pulmonary arterial hypertension (PAH) and to gain preliminary insights on the possibility of its treatment with oral drugs.

METHODS

Iron status was determined in 31 consecutive prevalent idiopathic patients with PAH. Iron depletion was defined as serum iron <10 mmol/L and decreased transferrin saturation irrespective of the coexistence of anaemia. Patients underwent laboratory examinations, 6-min walking test and echocardiography in the same day. A subgroup of iron depleted patients received one oral capsule/day containing 30 mg of pyrophosphate sucrosomial iron for 16 weeks. After this period all patients were re-evaluated.

RESULTS

Iron depletion was observed in 22 patients (71%), of whom 6 were also anaemic and 16 were not anaemic. Iron depletion was associated with higher systolic pulmonary artery pressure (60 [50-90] vs. 45 [40-50] mmHg, p = .007), greater prevalence of moderate to severe tricuspid regurgitation (36% vs. 0%, p = .039), lower tricuspid annular plane systolic excursion (23 [21-24] vs. 19 [18-20] mm; p = .025]) and higher left ventricular eccentricity index (1.35 vs. 1, p = .042). After 16 weeks of treatment, 6-min walking distance significantly improved (500 [390-500] vs. 530 [410-550] metres; p = .043).

CONCLUSIONS

Iron deficiency is highly prevalent in patients with PAH and is associated with worse clinical conditions. Treatment with oral sucrosomial iron is a therapeutic option which should be further investigated in future trials.

A multicentre prospective double blinded randomised controlled trial of intravenous iron (ferric Derisomaltose (FDI)) in Iron deficient but not anaemic patients with chronic kidney disease on functional status

BACKGROUND

Iron deficiency (ID) is common in patients with chronic kidney disease (CKD). Intravenous (IV) iron in heart failure leads to improvement in exercise capacity and improvement in quality-of-life measurements; however, data in patients with CKD are lacking.

METHODS

The Iron and the Heart Study was a prospective double blinded randomised study in non-anaemic CKD stages 3b-5 patients with ID which investigated whether 1000 mg of IV iron (ferric derisomaltose (FDI)) could improve exercise capacity in comparison to placebo measured at 1 and 3 months post infusion. Secondary objectives included effects on haematinic profiles and haemoglobin, safety analysis and quality of life questionnaires (QoL).

RESULTS

We randomly assigned 54 patients mean (SD) age for FDI (n = 26) 61.6 (10.1) years vs placebo (n = 28; 57.8 (12.9) years) and mean eGFR (33.2 (9.3) vs. 29.1 (9.6) ml/min/1.73m2) at baseline, respectively. Adjusting for baseline measurements, six-minute walk test (6MWT) showed no statistically significant difference between arms at 1 month (p = 0.736), or 3 months (p = 0.741). There were non-significant increases in 6MWT from baseline to 1 and 3 months in the FDI arm. Haemoglobin (Hb) at 1 and 3 months remained stable. There were statistically significant increases in ferritin (SF) and transferrin saturation (TSAT) at 1 and 3 months (p < 0.001). There was a modest numerical improvement in QoL parameters. There were no adverse events attributable to IV iron.

CONCLUSION

This study demonstrated a short-term beneficial effect of FDI on exercise capacity, but it was not significant despite improvements in parameters of iron status, maintenance of Hb concentration, and numerical increases in functional capacity and quality of life scores. A larger study will be required to confirm if intravenous iron is beneficial in iron deficient non-anaemic non-dialysis CKD patients without heart failure to improve the 6MWT.

TRIAL REGISTRATION

European Clinical Trials Database (EudraCT) No: 2014-004133-16 REC no: 14/YH/1209 Date First Registered: 2015-02-17 and date of end of trail 2015-05-23 Sponsor ref R1766 and Protocol No: IHI 141.

Iron Deficiency without Anemia Decreases Physical Endurance and Mitochondrial Complex I Activity of Oxidative Skeletal Muscle in the Mouse

Iron deficiency (ID), with or without anemia, is responsible for physical fatigue. This effect may be linked to an alteration of mitochondrial metabolism. Our aim was to assess the impact of ID on skeletal striated muscle mitochondrial metabolism. Iron-deficient non-anemic mice, obtained using a bloodletting followed by a low-iron diet for three weeks, were compared to control mice. Endurance was assessed using a one-hour submaximal exercise on a Rotarod device and activities of mitochondrial complexes I and IV were measured by spectrophotometry on two types of skeletal striated muscles, the soleus and the quadriceps. As expected, ID mice displayed hematologic markers of ID and reduced iron stores, although none of them were anemic. In ID mice, endurance was significantly reduced and activity of the respiratory chain complex I, normalized to citrate synthase activity, was significantly reduced in the soleus muscle but not in the quadriceps. Complex IV activities were not significantly different, neither in the soleus nor in the quadriceps. We conclude that ID without anemia is responsible for impaired mitochondrial complex I activity in skeletal muscles with predominant oxidative metabolism. These results bring pathophysiological support to explain the improved physical activity observed when correcting ID in human. Further studies are needed to explore the mechanisms underlying this decrease in complex I activity and to assess the role of iron therapy on muscle mitochondrial metabolism.

Intravenous iron for heart failure with evidence of iron deficiency: a meta-analysis of randomised trials

Background

The recent AFFIRM-AHF trial assessing the effect of intravenous (IV) iron on outcomes in patients hospitalised with worsening heart failure who had iron deficiency (ID) narrowly missed its primary efficacy endpoint of recurrent hospitalisations for heart failure (HHF) or cardiovascular (CV) death. We conducted a meta-analysis to determine whether these results were consistent with previous trials.

Methods

We searched for randomised trials of patients with heart failure investigating the effect of IV iron vs placebo/control groups that reported HHF and CV mortality from 1st January 2000 to 5th December 2020. Seven trials were identified and included in this analysis. A fixed effect model was applied to assess the effects of IV iron on the composite of first HHF or CV mortality and individual components of these.

Results

Altogether, 2,166 patients were included (n = 1168 assigned to IV iron; n = 998 assigned to control). IV iron reduced the composite of HHF or CV mortality substantially [OR 0.73; (95% confidence interval 0.59–0.90); p = 0.003]. Outcomes were consistent for the pooled trials prior to AFFIRM-AHF. Whereas first HHF were reduced substantially [OR 0.67; (0.54–0.85); p = 0.0007], the effect on CV mortality was uncertain but appeared smaller [OR 0.89; (0.66–1.21); p = 0.47].

Conclusion

Administration of IV iron to patients with heart failure and ID reduces the risk of the composite outcome of first heart failure hospitalisation or cardiovascular mortality, but this outcome may be driven predominantly by an effect on HHF. At least three more substantial trials of intravenous iron are underway.

Graphic abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s00392-021-01837-8.

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.

Iron deficiency as therapeutic target in heart failure: a translational approach

Heart failure (HF) is a potentially debilitating condition, with a prognosis comparable to many forms of cancer. It is often complicated by anemia and iron deficiency (ID), which have been shown to even further harm patients' functional status and hospitalization risk. Iron is a cellular micronutrient that is essential for oxygen uptake and transportation, as well as mitochondrial energy production. Iron is crucially involved in electrochemical stability, maintenance of structure, and contractility of cardiomyocytes. There is mounting evidence that ID indeed hampers the homeostasis of these properties. Animal model and stem cell research has verified these findings on the cellular level, while clinical trials that treat ID in HF patients have shown promising results in improving real patient outcomes, as electromechanically compromised cardiomyocytes translate to HF exacerbations and arrhythmias in patients. In this article, we review our current knowledge on the role of iron in cardiac muscle cells, the contribution of ID to anemia and HF pathophysiology and the capacity of IV iron therapy to ameliorate the patients' arrhythmogenic profile, quality of life, and prognosis.

Association of Baseline Anemia with Mid-Term Clinical Outcomes in Patients Who Underwent Trans-Radial Primary Percutaneous Coronary Intervention

Radial access is recommended for primary percutaneous coronary intervention (PCI), because it has fewer bleeding complications than trans-femoral PCI. However, even if trans-radial PCI is chosen, patients with ST-elevation myocardial infarction (STEMI) presenting with anemia on admission might have poor clinical outcomes. The aim of this retrospective study was to investigate whether anemia on admission was associated with mid-term clinical outcomes in patients who underwent trans-radial primary PCI. The primary endpoint was a composite of all-cause death, recurrent acute myocardial infarction, and readmission for heart failure. A total of 288 consecutive patients with STEMI who underwent trans-radial primary PCI were divided into an anemia group (n = 79) and a non-anemia group (n = 209). The median follow-up duration was 301 days. The anemia group was significantly older than the non-anemia group (77.3 ± 11.9 versus 64.4 ± 12.7 years, respectively; P < 0.001). There were significantly more females in the anemia group than in the non-anemia group (36.7% versus 14.4%, respectively; P < 0.001). Kaplan-Meier analysis revealed that the composite outcome-free survival was significantly worse in the anemia group than in the non-anemia group (P < 0.001). Multivariate Cox hazard model analysis revealed that hemoglobin levels on admission were significantly associated with the composite outcome (per 1 g/dL increase: hazard ratio 0.76, 95% confidence interval 0.66-0.88, P < 0.001) after controlling for confounding factors. In conclusion, baseline anemia was significantly associated with poor clinical outcomes. Patients with STEMI presenting with anemia should be managed carefully, even if trans-radial primary PCI is chosen.

Anaemia and iron deficiency in patients with rheumatoid arthritis and other chronic diseases

Anaemia is one of the most common symptoms accompanying many chronic diseases, e.g. collagenases, neoplasms, and chronic inflammations (inflammatory bowel disease, chronic kidney disease and heart failure). Iron deficiency anaemia is the most common type of anaemia (80%). It affects 1% to 2% of the population. Iron deficiency (ID) – absolute or functional – is characterised by reduced ferritin levels and transferrin saturation (TSAT) of less than 20%. Iron deficiency is the most common dietary deficiency. However, iron deficiency might be one of the common causes of anaemia of chronic disease (ACD). Anaemia affects 33% to 60% of patients with RA. Rheumatoid arthritis (RA) is a chronic immune-mediated systemic connective tissue disease, in which chronic inflammation of the synovial tissue of the joints damages articular cartilages, bones and other joint structures. The prevalence of RA is approximately 0.3% to 2%. Low haemoglobin levels in RA patients are significantly correlated with disability, activity and duration of the disease as well as damage to joints and joint pain. Treatment of anaemia in RA patients includes iron supplementation, blood transfusions, the use of erythropoiesis-stimulating agents, and treatment of the underlying condition. Biological treatments used in RA patients, such as e.g. infliximab, tocilizumab and anakinra, not only slow the progression of joint involvement but also prevent anaemia.

Iron deficiency without anaemia: a diagnosis that matters

Iron deficiency anaemia (IDA) currently affects 1.2 billion people and iron deficiency without anaemia (IDWA) is at least twice as common. IDWA is poorly recognised by clinicians despite its high prevalence, probably because of suboptimal screening recommendations. Diagnosing IDWA relies on a combination of tests, including haemoglobin and ferritin levels, as well as transferrin saturation. Although the causes of iron deficiency may sometimes be obvious, many tend to be overlooked. Iron sufficiency throughout pregnancy is necessary for maternal and foetal health. Preoperative IDWA must be corrected to reduce the risk of transfusion and postoperative anaemia. Oral iron is the first-line treatment for managing IDWA; however, intravenous supplementation should be used in chronic inflammatory conditions and when oral therapy is poorly tolerated or ineffective. This review considers the causes and clinical features of IDWA, calls for greater awareness of the condition, and proposes diagnostic and management algorithms.

ESA, Iron Therapy and New Drugs: Are There New Perspectives in the Treatment of Anaemia?

Anemia is a well-known consequence of chronic kidney disease (CKD); it is mainly due to a relative insufficiency of erythropoietin synthesis by the failing kidneys. Over the years, the combination of erythropoiesis stimulating agents (ESA) and iron has become the standard of care of anemia. All ESAs effectively increase hemoglobin (Hb) levels in a substantial percentage of patients. However, in the last decade, their use has been surrounded by safety issues in increased cardiovascular risk, especially when used at high doses in inflamed and hyporesponsive patients. This has led to the definition of a more cautious Hb target. Iron deficiency is very frequent in CKD patients, with a higher frequency in non-dialysis patients. Traditionally, iron supplementation is mostly used as supportive therapy for anemia control. However, the concept is growing that intravenous iron therapy per se could be beneficial in the presence of heart failure. A new class of drugs, prolyl hydroxylase domain (PHD) inhibitors (PHD inhibitors) is becoming available for the treatment of anemia in CKD patients. Theoretically, these agents have a number of advantages, the main ones being that of stimulating the synthesis of endogenous erythropoietin and increasing iron availability. The impact of their future use in clinical practice is still to be defined. Another possible strategy could be targeting serum hepcidin and its related pathways. This possibility is fascinating from the scientific point of view, but at present its development phase is still far from clinical application.

Safety and Effectiveness of an Accelerated Intravenous Iron Administration Protocol in Hospitalized Patients With Heart Failure

BACKGROUND

The ACC/AHA heart failure (HF) guidelines include a class IIb recommendation for intravenous (IV) iron replacement in patients with iron deficiency and New York Heart Association class II or III to improve functional status and quality of life. Several studies have addressed the use of IV iron formulations such as ferric carboxymaltose or iron sucrose in HF population; however, few studies focused on sodium ferric gluconate complex (SFGC).

OBJECTIVES

To assess the safety and effectiveness of an IV SFGC administration protocol in patients hospitalized with HF.

METHODS

A retrospective cohort study was conducted. We included patients admitted to the HF service from September 2017 to March 2018. The primary outcome was the frequency of adverse reactions. The secondary outcome was the odds of HF readmissions between the 2 groups (IV SFGC vs. control).

RESULTS

Of the 123 patients, 70 received IV iron (SFGC group) and 53 did not receive IV iron (control group). Five (7%) patients of the 70 in the SFGC group experienced adverse events, which included hypotension (n = 2, 2.8%), fever (n = 2, 2.8%) and myalgia (n = 2, 2.8%). Nine (12.8%) and 18 (25.7%) were readmitted within 30 days and 6 months respectively. In the control arm, 5 (9.4%) and 14 (26.4%) were admitted within 30 days and 6 months respectively. The odds of HF readmission at 30 days [OR 1.4 (95% CI: 0.45, 4.5)] and at 6 months [OR 0.96 (95% CI: 0.43, 2.2)] were similar in those who did not receive IV iron compared to those who received IV iron.

CONCLUSIONS

Sodium ferric gluconate complex given at an accelerated dosing schedule appears to provide a more efficient means to prescribe IV iron in the inpatient setting and is safe with a low frequency of hypotension, fevers, and myalgias.

Management of Anaemia of Chronic Disease: Beyond Iron-Only Supplementation

Chronic diseases are characterised by altered autophagy and protein metabolism disarrangement, resulting in sarcopenia, hypoalbuminemia and hypo-haemoglobinaemia. Hypo-haemoglobinaemia is linked to a worse prognosis independent of the target organ affected by the disease. Currently, the cornerstone of the therapy of anaemia is iron supplementation, with or without erythropoietin for the stimulation of haematopoiesis. However, treatment strategies should incorporate the promotion of the synthesis of heme, the principal constituent of haemoglobin (Hb) and of many other fundamental enzymes for human metabolism. Heme synthesis is controlled by a complex biochemical pathway. The limiting step of heme synthesis is D-amino-levulinic acid (D-ALA), whose availability and synthesis require glycine and succinil-coenzyme A (CoA) as precursor substrates. Consequently, the treatment of anaemia should not be based only on the sufficiency of iron but, also, on the availability of all precursor molecules fundamental for heme synthesis. Therefore, an adequate clinical therapeutic strategy should integrate a standard iron infusion and a supply of essential amino acids and vitamins involved in heme synthesis. We reported preliminary data in a select population of aged anaemic patients affected by congestive heart failure (CHF) and catabolic disarrangement, who, in addition to the standard iron therapy, were treated by reinforced therapeutic schedules also providing essential animo acids (AAs) and vitamins involved in the maintenance of heme. Notably, such individualised therapy resulted in a significantly faster increase in the blood concentration of haemoglobin after 30 days of treatment when compared to the nonsupplemented standard iron therapy.

Role of comorbidities in heart failure prognosis Part I: Anaemia, iron deficiency, diabetes, atrial fibrillation

Cardiovascular and non-cardiovascular comorbidities are frequently observed in heart failure patients, complicating the therapeutic management and leading to poor prognosis. The prompt recognition of associated comorbid conditions is of great importance to optimize the clinical management, the follow-up, and the treatment of patients affected by chronic heart failure. Anaemia and iron deficiency are commonly reported in all heart failure forms, have a multifactorial aetiology and are responsible for reduced exercise tolerance, impaired quality of life, and poor long-term prognosis. Diabetes mellitus is highly prevalent in heart failure and a poor glycaemic control is associated with worst outcome. Two specific heart failure forms are usually observed in diabetic patients: an ischaemic cardiomyopathy or a typical diabetic cardiomyopathy. The implementation of use of sodium-glucose cotransporter-2 inhibitors will much improve in the near future the long-term prognosis of patients affected by heart failure and diabetes. Among cardiovascular comorbidities, atrial fibrillation is the most common arrhythmic disease of heart failure patients and it is still not clear whether its presence should be considered as a prognostic indicator or as a marker of advanced disease. The aim of the present review was to explore the clinical and prognostic impact of anaemia and iron deficiency, diabetes mellitus, and atrial fibrillation in patients affected by chronic heart failure.

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.

Intravenous iron in heart failure and chronic kidney disease

Intravenous iron therapy is increasingly being used worldwide to treat anemia in chronic kidney disease and more recently iron deficiency in heart failure. Promising results were obtained in randomized clinical trials in the latter, showing symptomatic and functional capacity improvement with intravenous iron therapy. Meanwhile, confirmation of clinical benefit in hard-endpoints such as mortality and hospitalization is expected in large clinical trials that are already taking place. In chronic kidney disease, concern about iron overload is being substituted by claims of direct cardiovascular benefit of iron supplementation, as suggested by preliminary studies in heart failure. We discuss the pitfalls of present studies and gaps in knowledge, stressing the known differences between iron metabolism in heart and renal failure. Systemic and cellular iron handling and the role of hepcidin are reviewed, as well as the role of iron in atherosclerosis, especially in view of its relevance to patients undergoing dialysis. We summarize the evidence available concerning iron overload, availability and toxicity in CKD, that should be taken into account before embracing aggressive intravenous iron supplementation.

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.

The emerging role of iron in heart failure and vascular calcification in CKD

Iron deficiency is a frequent comorbidity of cardiovascular (CV) diseases and nearly 50% of patients with heart failure (HF) with or without anaemia have low levels of available iron. There is a strong association between anaemia and the increase in mortality and hospitalizations in patients with CV disease and HF. Moreover, anaemia and chronic kidney disease (CKD) often coexist in patients with HF, with anaemia increasing the risk of death in these subjects and with a further increased risk in CKD population. The evidence that the treatment of iron deficiency and the increase in haemoglobin are associated with a better prognosis in HF patients has elicited new interest in the utilization of iron in HF and CKD patients. One of the central players in CV disease is vascular calcification (VC), which has been recognized as a major independent risk factor for incident CV disease and overall mortality in chronic disease patients. In this review, we summarize the evidences generated by clinical trials aimed to study the effect of iron deficiency correction, the effect of iron-based phosphate binder in in vivo models of kidney failure and the effect of iron in in vitro models of VC, trying to give an overview of the present knowledge on iron effect and its mechanisms of action.

Efficacy and safety of iron therapy in patients with chronic heart failure and iron deficiency: a systematic review and meta-analysis based on 15 randomised controlled trials

Trials studying iron administration in patients with chronic heart failure (CHF) and iron deficiency (ID) have sprung up these years but the results remain inconsistent. The aim of this meta-analysis was to comprehensively evaluate the efficacy and safety of iron therapy in patients with CHF and ID. A literature search was conducted across PubMed, Embase, Cochrane Library, OVID and Web of Science up to 31 July 2019 to search for randomised controlled trials (RCT) comparing iron therapy with placebo in CHF with ID, regardless of presence of anaemia. Published studies reporting data of any of the following outcomes were included: all-cause death, cardiovascular hospitalisation, adverse events, New York Heart Association (NYHA) functional class, left ventricular ejection fraction (LVEF), N-terminal pro b-type natriuretic peptide, peak oxygen consumption, 6 min walking test (6MWT) distance and quality of life (QoL) parameters. 15 RCTs with a total of 1627 patients (911 in iron therapy and 716 in control) were included. Iron therapy was demonstrated to reduce the risk of cardiovascular hospitalisation (OR 0.35, 95% CI 0.12 to 0.99, p=0.049), but was ineffective in reducing all-cause death (OR 0.59, 95% CI 0.33 to 1.06, p=0.078) or cardiovascular death (OR 0.80, 95% CI 0.39 to 1.63, p=0.540). Iron therapy resulted in a reduction in NYHA class (mean difference (MD) -0.73, 95% CI -0.99 to -0.47, p<0.001), an increase in LVEF (MD +4.35, 95% CI 0.69 to 8.00, p=0.020), 6MWT distance (MD +35.44, 95% CI 11.55 to 59.33, p=0.004) and an improvement in QoL: EQ-5D score (MD +4.07, 95% CI 0.84 to 7.31, p=0.014); Minnesota Living With Heart Failure Questionnaire score (MD -19.47, 95% CI -23.36 to -15.59, p<0.001) and Patients Global Assessment (PGA) scale (MD 0.71, 95% CI 0.32 to 1.10, p<0.001). There was no significant difference in adverse events or serious adverse events between iron treatment group and control group. Iron therapy reduces cardiovascular hospitalisation in patients with CHF with ID, and additionally improves cardiac function, exercise capacity and QoL in patients with CHF with ID and anaemia, without an increase of adverse events.

Anaemia, iron status, and gender predict the outcome in patients with chronic heart failure

Aims

Anaemia and iron deficiency (ID) are frequently found in patients with chronic heart failure (CHF) and associated with adverse outcome. However, it is unclear whether absolute [transferrin saturation (TSAT) <20%, ferritin <100 μg/L] or inflammation‐driven functional ID (TSAT <20%, ferritin >100 μg/L) with and without anaemia had similar or different consequences for such patients.

Methods and results

Within this retrospective cohort study, 2223 patients (1601 men and 622 women) with CHF, referred to our department, between 2000 and 2018, were followed for a median time of 84 months. Anaemia was found in 393 patients and was an independent predictor for an adverse outcome [HR 2.164 (95% CI 1.865–2.512), P < 0.001]. In 674 patients with available parameters of iron metabolism, ID was present in 228 patients and was associated with an unfavourable outcome [HR 1.499 (95% CI 1.158–1.940), P = 0.002]. ID was best predicting an adverse outcome in men ≤59 years, with heart failure with reduced ejection fraction, preserved kidney function, no inflammation, and a body mass index (BMI) ≥25.5 kg/m². Functional ID in women and absolute ID in men were associated with poor prognosis. Of note, TSAT <20% but not low ferritin levels were predictive for an adverse outcome. Anaemic patients with high ferritin levels, advanced inflammation, older age, low BMI, male gender, and reduced glomerular filtration rate had the worst prognosis.

Conclusions

Anaemia and low tissue iron availability as reflected by TSAT <20% are negative predictors of outcome in patients with CHF. Systemic inflammation, renal function, BMI, age, and gender are important contributors for the clinical course.

Structural and functional abnormalities in iron-depleted heart

Iron deficiency (ID) is a common and ominous comorbidity in heart failure (HF) and predicts worse outcomes, independently of the presence of anaemia. Accumulated data from animal models of systemic ID suggest that ID is associated with several functional and structural abnormalities of the heart. However, the exact role of myocardial iron deficiency irrespective of systemic ID and/or anaemia has been elusive. Recently, several transgenic models of cardiac-specific ID have been developed to investigate the influence of ID on cardiac tissue. In this review, we discuss structural and functional cardiac consequences of ID in these models and summarize data from clinical studies. Moreover, the beneficial effects of intravenous iron supplementation are specified.

Improving exercise capacity and quality of life using non-invasive heart failure treatments: evidence from clinical trials

Endpoints of large-scale trials in chronic heart failure have mostly been defined to evaluate treatments with regard to hospitalizations and mortality. However, patients with heart failure are also affected by very severe reductions in exercise capacity and quality of life. We aimed to evaluate the effects of heart failure treatments on these endpoints using available evidence from randomized trials. Interventions with evidence for improvements in exercise capacity include physical exercise, intravenous iron supplementation in patients with iron deficiency, and - with less certainty - testosterone in highly selected patients. Erythropoiesis-stimulating agents have been reported to improve exercise capacity in anaemic patients with heart failure. Sinus rhythm may have some advantage when compared with atrial fibrillation, particularly in patients undergoing pulmonary vein isolation. Studies assessing treatments for heart failure co-morbidities such as sleep-disordered breathing, diabetes mellitus, chronic kidney disease and depression have reported improvements of exercise capacity and quality of life; however, the available data are limited and not always consistent. The available evidence for positive effects of pharmacologic interventions using angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, beta-blockers, and mineralocorticoid receptor antagonists on exercise capacity and quality of life is limited. Studies with ivabradine and with sacubitril/valsartan suggest beneficial effects at improving quality of life; however, the evidence base is limited in particular for exercise capacity. The data for heart failure with preserved ejection fraction are even less positive, only sacubitril/valsartan and spironolactone have shown some effectiveness at improving quality of life. In conclusion, the evidence for state-of-the-art heart failure treatments with regard to exercise capacity and quality of life is limited and appears not robust enough to permit recommendations for heart failure. The treatment of co-morbidities may be important for these patient-related outcomes. Additional studies on functional capacity and quality of life in heart failure are required.

Management of Iron-Deficiency Anemia on Inpatients and Appropriate Discharge and Follow-Up

Background

The aims of the study were to identify appropriate supplementation of iron for inpatients and to identify factors involved in appropriate discharge documentation and follow-up.

Methods

This was a retrospective analysis of 103 patients at a community hospital in New York City.

Results

A total of 57 (57/103, 55.3%) patients were admitted due to symptomatic anemia. Twenty (20/103, 19.4%) of those with iron-deficiency anemia had either esophagogastroduodenoscopy or colonoscopy. Gastroenterologist or hematologist was consulted for 45/103 (43.7%). Inpatient iron supplementation was given for 62/103 (60.2%) of patients; and 43/103 (41.7%) had blood transfusion. Upon discharge, 50/103 (48.5%) had appropriate documentation of iron-deficiency anemia on discharge paperwork. Appropriate follow-up was done for 54/103 (52.4%). Iron supplementation was provided for 53/103 (51.5%) of patients. Having inpatient esophagogastroduodenoscopy or colonoscopy, blood transfusion, or symptomatic anemia had a statistical significance for likelihood of appropriate discharge documentation.

Conclusions

Iron-deficiency anemia can have high rates of mortality and morbidity in the population. Appropriate discharge of patients with iron-deficiency anemia and factors related to this are paramount for clinicians in order to have the best patient outcomes.

Iron Sucrose: A Wealth of Experience in Treating Iron Deficiency

Iron deficiency and iron-deficiency anemia are associated with increased morbidity and mortality in a wide range of conditions. In many patient populations, this can be treated effectively with oral iron supplementation; but in patients who are unable to take or who do not respond to oral iron therapy, intravenous iron administration is recommended. Furthermore, in certain conditions, such as end-stage kidney disease, chronic heart failure, and inflammatory bowel disease, intravenous iron administration has become first-line treatment. One of the first available intravenous iron preparations is iron sucrose (Venofer®), a nanomedicine that has been used clinically since 1949. Treatment with iron sucrose is particularly beneficial owing to its ability to rapidly increase hemoglobin, ferritin, and transferrin saturation levels, with an acceptable safety profile. Recently, important new data relating to the use of iron sucrose, including the findings from the landmark PIVOTAL trial in patients with end-stage kidney disease, have been reported. Several years ago, a number of iron sucrose similars became available, although there have been concerns about the clinical appropriateness of substituting the original iron sucrose with an iron sucrose similar because of differences in efficacy and safety. This is a result of the complex and unique physicochemical properties of nanomedicines such as iron sucrose, which make copying the molecule difficult and problematic. In this review, we summarize the evidence accumulated during 70 years of clinical experience with iron sucrose in terms of efficacy, safety, and cost-effectiveness.

Intravenous iron: a framework for changing the management of iron deficiency

For decades intravenous iron was considered dangerous. Newer formulations with carbohydrate cores binding elemental iron more tightly allow complete iron replacement within 15-60 min in one visit. Meta-analyses and prospective comparisons of different formulations support equivalent safety to placebo with less toxicity than oral iron. Of the available formulations, the preponderance of published evidence supports equal safety and efficacy. In this Viewpoint, we report evidence supporting repositioning of intravenous iron to the frontline in multiple disorders with iron deficiency, which include heart failure, chronic kidney disease, inflammatory bowel disease, patient blood management in the perioperative period, and obstetrics and gynaecology. We have also highlighted neonatal evidence supporting the inadequacy of oral iron in late pregnancy, a critical period of iron need for normal foetal brain development. Physicians should consider prioritising the use of intravenous iron rather than oral iron as a treatment for iron deficiency in some of these clinical scenarios.

Effect of ferric-carboxy maltose on oxygen kinetics and functional status in heart failure patients with iron deficiency

There is a very high prevalence of iron deficiency anemia in patients with systolic heart failure. The present study is a prospective, parallel, 1:1 randomized controlled trial of intravenous ferric-carboxy maltose compared with standard of care in patients with heart failure. A total of 70 patients who presented to us with symptomatic chronic heart failure were included and randomly assigned to either groups (35 per group). Post 12 weeks, there were improvements noticed in peak VO₂, New York Heart Association functional classification, 6-min walk test distance covered and reduction in Minnesota Living with Heart Failure Questionnaire score in the ferric-carboxy maltose as compared with standard of care group. However, no improvement in ejection fraction was noticed.

Iron deficiency is commonly seen in patients with heart failure. This study was performed to observe the effect of intravenous iron therapy (ferric-carboxy maltose) in this population. The outcome showed significant benefit in symptoms and improvement in quality of life. These results are in concordance with other similar trials. Therefore, simple intravenous iron replacement along with other heart failure measures can make life easier for patients with heart failure.

The effect of iron deficiency on cardiac resynchronization therapy: results from the RIDE-CRT Study

Aims

Cardiac resynchronization therapy (CRT) improves functional status, induces reverse left ventricular remodelling, and reduces hospitalization and mortality in patients with symptomatic heart failure, left ventricular systolic dysfunction, and QRS prolongation. However, the impact of iron deficiency on CRT response remains largely unclear. The purpose of the study was to assess the effect of functional and absolute iron deficiency on reverse cardiac remodelling, clinical response, and outcome after CRT implantation.

Methods and results

The relation of iron deficiency and cardiac resynchronization therapy response (RIDE‐CRT) study is a prospective observational study. We enrolled 77 consecutive CRT recipients (mean age 71.3 ± 10.2 years) with short‐term follow‐up of 3.3 ± 1.9 months and long‐term follow‐up of 13.0 ± 3.2 months. Primary endpoints were reverse cardiac remodelling on echocardiography and clinical CRT response, assessed by change in New York Heart Association classification. Echocardiographic CRT response was defined as relative improvement of left ventricular ejection fraction ≥ 20% or left ventricular global longitudinal strain ≥ 20%. Secondary endpoints were hospitalization for heart failure and all‐cause mortality (mean follow‐up of 29.0 ± 8.4 months). At multivariate analysis, iron deficiency was identified as independent predictor of echocardiographic (hazard ratio 4.97; 95% confidence interval 1.15–21.51; P = 0.03) and clinical non‐response to CRT (hazard ratio 4.79; 95% confidence interval 1.30–17.72, P = 0.02). We found a significant linear‐by‐linear association between CRT response and type of iron deficiency (P = 0.004 for left ventricular ejection fraction improvement, P = 0.02 for left ventricular global longitudinal strain improvement, and P = 0.003 for New York Heart Association response). Iron deficiency was also significantly associated with an increase in all‐cause mortality (P = 0.045) but not with heart failure hospitalization.

Conclusions

Iron deficiency is a negative predictor of effective CRT therapy as assessed by reverse cardiac remodelling and clinical response. Assessment of iron substitution might be a relevant treatment target to increase CRT response and outcome in chronic heart failure patients.

Exercise Intolerance in Patients With Heart Failure: JACC State-of-the-Art Review

Exercise intolerance is the cardinal symptom of heart failure (HF) and is of crucial relevance, because it is associated with a poor quality of life and increased mortality. While impaired cardiac reserve is considered to be central in HF, reduced exercise and functional capacity are the result of key patient characteristics and multisystem dysfunction, including aging, impaired pulmonary reserve, as well as peripheral and respiratory skeletal muscle dysfunction. We herein review the different modalities to quantify exercise intolerance, the pathophysiology of HF, and comorbid conditions as they lead to reductions in exercise and functional capacity, highlighting the fact that distinct causes may coexist and variably contribute to exercise intolerance in patients with HF.

Iron and Heart Failure: Diagnosis, Therapies, and Future Directions

To date, 3 clinical trials have shown symptomatic benefit from the use of intravenous (IV) iron in patients with heart failure (HF) with low serum iron. This has led to recommendations in support of the use of IV iron in this population. However, the systemic and cellular mechanisms of iron homeostasis in cardiomyocyte health and disease are distinct, complex, and poorly understood. Iron metabolism in HF appears dysregulated, but it is still unclear whether the changes are maladaptive and pathologic or compensatory and protective for the cardiomyocytes. The serum markers of iron deficiency in HF do not accurately reflect cellular and mitochondrial iron levels, and the current definition based on the ferritin and transferrin saturation values is broad and inclusive of patients who do not need IV iron. This is particularly relevant in view of the potential risks that are associated with the use of IV iron. Reliable markers of cellular iron status may differentiate subgroups of HF patients who would benefit from cellular and mitochondrial iron chelation rather than IV iron.

Keeping heart homeostasis in check through the balance of iron metabolism

Highly active cardiomyocytes need iron for their metabolic activity. In physiological conditions, iron turnover is a delicate process which is dependent on global iron supply and local autonomous regulatory mechanisms. Though less is known about the autonomous regulatory mechanisms, data suggest that these mechanisms can preserve cellular iron turnover even in the presence of systemic iron disturbance. Therefore, activity of local iron protein machinery and its relationship with global iron metabolism is important to understand cardiac iron metabolism in physiological conditions and in cardiac disease. Our knowledge in this respect has helped in designing therapeutic strategies for different cardiac diseases. This review is a synthesis of our current knowledge concerning the regulation of cardiac iron metabolism. In addition, different models of cardiac iron dysmetabolism will be discussed through the examples of heart failure (cardiomyocyte iron deficiency), myocardial infarction (acute changes in cardiac iron turnover), doxorubicin-induced cardiotoxicity (cardiomyocyte iron overload in mitochondria), thalassaemia (cardiomyocyte cytosolic and mitochondrial iron overload) and Friedreich ataxia (asymmetric cytosolic/mitochondrial cardiac iron dysmetabolism). Finally, future perspectives will be discussed in order to resolve actual gaps in knowledge, which should be helpful in finding new treatment possibilities in different cardiac diseases.

Intravenous iron therapy for non-anaemic, iron-deficient adults

BACKGROUND

Iron deficiency is one of the most common nutritional deficiencies, and has a number of physiological manifestations. Early, or non-anaemic iron deficiency can result in fatigue and diminished exercise capacity. Oral iron preparations have a high incidence of intolerable side effects, and are ineffective in certain forms of iron deficiency. Consequently, intravenous iron preparations are increasingly used in the treatment of non-anaemic iron deficiency. The newer, more stable iron preparations in particular purport to have a lower incidence of side effects, and are now used across a range of different patient populations.

OBJECTIVES

To assess the effects of intravenous iron therapy in the treatment of adults with non-anaemic iron deficiency.

SEARCH METHODS

On 18 October 2019 we electronically searched CENTRAL, MEDLINE, Embase, two further databases and two trials registries 2019. We handsearched the references of full-text extracted studies, and contacted relevant study authors for additional data.

SELECTION CRITERIA

We included randomised controlled trials that compared any intravenous iron preparation to placebo in adults. We excluded other forms of comparison such as oral iron versus placebo, intramuscular iron versus placebo, or intravenous iron studies where other iron preparations were used as the comparator. We also excluded studies involving erythropoietin therapy or obstetric populations.

DATA COLLECTION AND ANALYSIS

Two review authors screened references for eligibility, extracted data and assessed risk of bias. We resolved differences in opinion through discussion and consensus, and where necessary, involved a third review author to adjudicate disputes. We contacted study authors to request additional data where appropriate. The primary outcome measures were haemoglobin concentration at the end of follow-up, and quality-of-life scores at end of follow-up. Secondary outcome measures were serum ferritin, peak oxygen consumption (as measured by cardiopulmonary exercise testing), adverse effects (graded as mild to moderate and severe) and bacterial infection. We pooled data for continuous outcomes, which we then reported as mean differences (MDs) with 95% confidence intervals (CIs). We reported quality-of-life metrics as standardised mean difference (SMD), and then converted them back into a more familiar measure, the Piper Fatigue Scale. We analysed dichotomous outcomes as risk ratios (RRs). Given an expected degree of heterogeneity, we used a random-effects model for all outcomes. We performed the analysis with the software package Review Manager 5.

MAIN RESULTS

This review includes 11 studies with 1074 participants. Outcome metrics for which data were available (haemoglobin concentration, quality-of-life scores, serum ferritin, peak oxygen consumption and mild to moderate adverse effects) were similar across the included studies. The incidence of severe adverse events across all studies was zero. None of the studies measured bacterial infection as a specific outcome metric. Substantial heterogeneity influenced the results of the meta-analysis, arising from differing patient populations, definitions of iron deficiency, iron preparations and dosing regimens, and time to end of follow-up. Consequently, many outcomes are reported with small group sizes and wide confidence intervals, with a subsequent downgrading in the quality of evidence. The level of bias in many included studies was high, further reducing confidence in the robustness of the results. We found that intravenous iron therapy may lead to a small increase in haemoglobin concentration of limited clinical significance compared to placebo (MD 3.04 g/L, 95% CI 0.65 to 5.42; I2 = 42%; 8 studies, 548 participants; low-quality evidence). Quality-of-life scores (Piper Fatigue Scale MD 0.73, 95% CI 0.29 to 1.18; I2 = 0%; studies = 3) and peak oxygen consumption (MD 2.77 mL/kg/min, 95% CI -0.89 to 6.43; I2 = 36%; 2 studies, 32 participants) were associated with very low-quality evidence, and we remain uncertain about the role of intravenous iron for these metrics. We were unable to present pooled estimates for the outcomes of serum ferritin at the end of follow-up or mild to moderate adverse effects due to extreme statistical heterogeneity. Ultimately, despite the results of the meta-analysis, the low- or very low-quality evidence for all outcomes precludes any meaningful interpretation of results beyond suggesting that further research is needed. We performed a Trial Sequential Analysis for all major outcomes, none of which could be said to have reached a necessary effect size.

AUTHORS' CONCLUSIONS

Current evidence is insufficient to show benefit of intravenous iron preparations for the treatment of non-anaemic iron deficiency across a variety of patient populations, beyond stating that it may result in a small, clinically insignificant increase in haemoglobin concentration. However, the certainty for even this outcome remains limited. Robust data for the effectiveness of intravenous iron for non-anaemic iron deficiency is still lacking, and larger studies are required to assess the effect of this therapy on laboratory, patient-centric, and adverse-effect outcomes.

Iron therapy for preoperative anaemia

BACKGROUND

Preoperative anaemia is common and occurs in 5% to 76% of patients preoperatively. It is associated with an increased risk of perioperative allogeneic blood transfusion, longer hospital stay, and increased morbidity and mortality. Iron deficiency is one of the most common causes of anaemia. Oral and intravenous iron therapy can be used to treat anaemia. Parenteral iron preparations have been shown to be more effective in conditions such as inflammatory bowel disease, chronic heart failure and postpartum haemorrhage due to rapid correction of iron stores. A limited number of studies has investigated iron therapy for the treatment of preoperative anaemia. The aim of this Cochrane Review is to summarise the evidence for iron supplementation, both enteral and parenteral, for the management of preoperative anaemia.

OBJECTIVES

To evaluate the effects of preoperative iron therapy (enteral or parenteral) in reducing the need for allogeneic blood transfusions in anaemic patients undergoing surgery.

SEARCH METHODS

We ran the search on 30 July 2018. We searched the Cochrane Injuries Group's Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL, the Cochrane Library), Ovid MEDLINE(R), Ovid MEDLINE(R) In-Process & Other Non-Indexed Citations, Ovid MEDLINE(R) Daily and Ovid OLDMEDLINE(R), Embase Classic and Embase (Ovid), CINAHL Plus (EBSCO), PubMed, and clinical trials registries, and we screened reference lists. We ran a top-up search on 28 November 2019; one study is now awaiting classification.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) that compared preoperative iron monotherapy to placebo, no treatment, standard care or another form of iron therapy for anaemic adults undergoing surgery. We defined anaemia as haemoglobin values less than 13 g/dL for males and 12 g/dL for non-pregnant females.

DATA COLLECTION AND ANALYSIS

Two review authors collected data and a third review author checked all collected data. Data were collected on the proportion of patients who receive a blood transfusion, the amount of blood transfused per patient (units), quality of life, ferritin levels and haemoglobin levels, measured as continuous variables at the following predetermined time points: pretreatment (baseline), preoperatively but postintervention, and postoperatively. We performed statistical analysis using the Cochrane software, Review Manager 5. We summarised outcome data in tables and forest plots. We used the GRADE approach to describe the quality of the body of evidence.

MAIN RESULTS

Six RCTs, with a total of 372 participants, evaluated preoperative iron therapy to correct anaemia before planned surgery. Four studies compared iron therapy (either oral (one study) or intravenous (three studies)) with no treatment, placebo or usual care, and two studies compared intravenous iron therapy with oral iron therapy. Iron therapy was delivered over a range of periods that varied from 48 hours to three weeks prior to surgery. The 372 participants in our analysis fall far short of the 819 required - as calculated by our information size calculation - to detect a 30% reduction in blood transfusions. Five trials, involving 310 people, reported the proportion of participants who received allogeneic blood transfusions. Meta-analysis of iron therapy versus placebo or standard care showed no difference in the proportion of participants who received a blood transfusion (risk ratio (RR) 1.21, 95% confidence interval (CI) 0.87 to 1.70; 4 studies, 200 participants; moderate-quality evidence). Only one study that compared oral versus intravenous iron therapy measured this outcome, and reported no difference in risk of transfusion between groups. There was no difference between the iron therapy and placebo/standard care groups for haemoglobin level preoperatively at the end of the intervention (mean difference (MD) 0.63 g/dL, 95% CI -0.07 to 1.34; 2 studies, 83 participants; low-quality evidence). However, intravenous iron therapy produced an increase in preoperative postintervention haemoglobin levels compared with oral iron (MD 1.23 g/dL, 95% CI 0.80 to 1.65; 2 studies, 172 participants; low-quality evidence). Ferritin levels were increased by intravenous iron, both when compared to standard care ((MD 149.00, 95% CI 25.84 to 272.16; 1 study, 63 participants; low-quality evidence) or to oral iron (MD 395.03 ng/mL, 95% CI 227.72 to 562.35; 2 studies, 151 participants; low-quality evidence). Not all studies measured quality of life, short-term mortality or postoperative morbidity. Some measured the outcomes, but did not report the data, and the studies which did report the data were underpowered. Therefore, uncertainty remains regarding these outcomes. The inclusion of new research in the future is very likely to change these results.

AUTHORS' CONCLUSIONS

The use of iron therapy for preoperative anaemia does not show a clinically significant reduction in the proportion of trial participants who received an allogeneic blood transfusion compared to no iron therapy. Results for intravenous iron are consistent with a greater increase in haemoglobin and ferritin when compared to oral iron, but do not provide reliable evidence. These conclusions are drawn from six studies, three of which included very small numbers of participants. Further, well-designed, adequately powered, RCTs are required to determine the true effectiveness of iron therapy for preoperative anaemia. Two studies are currently in progress, and will include 1500 randomised participants.

[Position Paper. The role of iron deficiency in patients with chronic heart failure and current corrective approaches]

.