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

Iron deficiency and supplementation in heart failure

Non-anaemic iron deficiency (NAID) is a strategic target in cardiovascular medicine because of its association with a range of adverse effects in various conditions. Endeavours to tackle NAID in heart failure have yielded mixed results, exposing knowledge gaps in how best to define 'iron deficiency' and the handling of iron therapies by the body. To address these gaps, we harness the latest understanding of the mechanisms of iron homeostasis outside the erythron and integrate clinical and preclinical lines of evidence. The emerging picture is that current definitions of iron deficiency do not assimilate the multiple influences at play in patients with heart failure and, consequently, fail to identify those with a truly unmet need for iron. Additionally, current iron supplementation therapies benefit only certain patients with heart failure, reflecting differences in the nature of the unmet need for iron and the modifying effects of anaemia and inflammation on the handling of iron therapies by the body. Building on these insights, we identify untapped opportunities in the management of NAID, including the refinement of current approaches and the development of novel strategies. Lessons learned from NAID in cardiovascular disease could ultimately translate into benefits for patients with other chronic conditions such as chronic kidney disease, chronic obstructive pulmonary disease and cancer.

The findings of a service evaluation on the practice of assessment and treatment of iron deficiency in people admitted to a UK hospital with decompensated Heart Failure

BACKGROUND

Iron Deficiency (ID) is common in Heart Failure (HF) and associated with poor outcomes. Replacement with intravenous (IV) iron can improve functional status, quality of life and risk of unplanned admission. In 2015/16 a local service evaluation was performed which found that of people admitted with HF, only 27.5 % had assessment of iron status, and when identified, replacement occurred in fewer than half. Education strategies were employed to increase awareness of the importance of assessment and correction.

OBJECTIVES

To assess if practice had improved following education strategies.

METHODS

A review of 220 patient records for people admitted with HF in 2020/21 to establish if iron status assessed, presence of ID, and whether if ID identified it was treated, and by which route. Trends in 2020/21 data were explored in sub-groups by age, sex, type of HF, anaemia status, input from HF specialists and type of ID.

RESULTS

Compared to 2015/16, more assessments of iron status were performed (45% vs 27.5 %), ID was corrected more frequently (57% vs 46 %) and increased use of the IV route for replacement (83% vs 58 %) CONCLUSIONS: Despite the impact of COVID-19 on usual care in 2020/21, improvement was seen in proportion of assessment and treatment of ID following simple education strategies for key stakeholders. There may be scope to improve practice further if the findings remain similar post pandemic. If so, a formal Quality Improvement approach may be helpful.

Intravenous iron for acute and chronic heart failure with reduced ejection fraction (HFrEF) patients with iron deficiency: An updated systematic review and meta-analysis

Patients with heart failure (HF) and iron deficiency are at increased risk of adverse clinical outcomes. We searched databases for randomised controlled trials that compared IV iron to placebo, in patients with HF with reduced ejection fraction (HFrEF). A total of 7,813 participants, all having HFrEF with 3,998 receiving IV iron therapy, and 3,815 control recipients were included. There was a significant improvement in Kansas City Cardiomyopathy Questionnaire favouring IV iron with MD 7.39, 95% CI [3.55, 11.22], p = 0.0002. Subgroup analysis, based on acute and chronic HF, has displayed a sustained statistical significance. Additionally, a significant increase in the left ventricular ejection fraction % was observed, with MD 3.76, 95% CI [2.32, 5.21], p < 0.00001. A significant improvement in 6-min walk test was noted, with MD 34.87, 95% CI [20.02, 49.72], p < 0.00001. Furthermore, IV iron showed significant improvement in NYHA class, peak VO2, serum ferritin, and haemoglobin levels. Finally, despite the lack of difference in terms of all-cause hospitalisation and HF-related death, IV iron was associated with a significant reduction in HF-related, any cardiovascular reason hospitalisations, and all-cause death; which supports the need for implementation of IV iron as a standard of care in patients with HF and iron deficiency.

[The effect of the treatmet of iron on patients with failure heart and insufficient of iron. An Meta-analisis of randomized clinical trials]

INTRODUCTION

Approximately 45% of patients with heart failure had iron deficiency for the rest of their lives.

OBJECTIVE

To determine the effect of iron treatment in patients with heart failure and iron deficiency or anemia.

MATERIALS AND METHODS

The studies were selected in: PubMed, Scopus, Cochrane and Google Scholar, from the beginning of June to July 2023. The selected articles that met the inclusion criteria, the relevant information of the studies were collected according to the selection variables and were recorded in the Revman 5.0 program of the Cochrane collaboration. The primary outcome was composed of hospitalization for heart failure or cardiovascular death.

RESULTS

Of the 7 included studies, 6717 patients were obtained, the average age was 70 years with a predominance of the male gender (57%). The primary outcome was lower in patients in the control group compared to the placebo group (OR, 0.62; 95%CI, 0.54-0.70). The 6-minute walk test (6-MWT) was improved in the iron-supplemented group compared to the placebo group (OR, 0.79; 95%CI, 0.64-0.98). Adverse events were fewer in the iron supplement group compared to the placebo group (OR, 0.78; 95%CI, 0.67-0.91).

CONCLUSION

In this meta-analysis of randomized controlled trials, the effect of iron supplementation is found to reduce the incidence rate of hospitalization for heart failure or cardiovascular death. In addition to a reduction in adverse events, such as gastrointestinal and neurological disorders, it also improves 6-MWT.

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.

Iron Dyshomeostasis and Mitochondrial Function in the Failing Heart: A Review of the Literature

Cardiac contraction and relaxation require a substantial amount of energy provided by the mitochondria. The failing heart is adenosine triphosphate (ATP)- and creatine-depleted. Studies have found iron is involved in almost every aspect of mitochondrial function, and previous studies have shown myocardial iron deficiency in heart failure (HF). Many clinicians advocated intravenous iron repletion for HF patients meeting the conventional criteria for systemic iron deficiency. While clinical trials showed improved quality of life, iron repletion failed to significantly impact survival or significant cardiovascular adverse events. There is evidence that in HF, labile iron is trapped inside the mitochondria causing oxidative stress and lipid peroxidation. There is also compelling preclinical evidence demonstrating the detrimental effects of both iron overload and depletion on cardiomyocyte function. We reviewed the mechanisms governing myocardial and mitochondrial iron content. Mitochondrial dynamics (i.e., fusion, fission, mitophagy) and the role of iron were also investigated. Ferroptosis, as an important regulated cell death mechanism involved in cardiomyocyte loss, was reviewed along with agents used to manipulate it. The membrane stability and iron content of mitochondria can be altered by many agents. Some studies are showing promising improvement in the cardiomyocyte function after iron chelation by deferiprone; however, whether the in vitro and in vivo findings will be reflected on on clinical grounds is still unclear. Finally, we briefly reviewed the clinical trials on intravenous iron repletion. There is a need for more well-simulated animal studies to shed light on the safety and efficacy of chelation agents and pave the road for clinical studies.

Iron Deficiency in Chronic Pediatric Heart Failure: Overall Assessment and Outcomes in Dilated Cardiomyopathy

OBJECTIVE

To evaluate the frequency of iron status assessment in pediatric heart failure and the prevalence and adverse effects of absolute iron deficiency in dilated cardiomyopathy-induced heart failure.

STUDY DESIGN

We retrospectively reviewed records of children with chronic heart failure at our center between 2010 and 2020. In children with dilated cardiomyopathy, we analyzed baseline cardiac function, hemoglobin level, and subsequent risk of composite adverse events (CAE), including death, heart transplant, ventricular assist device (VAD) placement, and transplant registry listing. Absolute iron deficiency and iron sufficiency were defined as transferrin saturations <20% and ≥30%, respectively; and indeterminant iron status as 20%-29%.

RESULTS

Of 799 patients with chronic heart failure, 471 (59%) had no iron-related laboratory measurements. Of 68 children with dilated cardiomyopathy, baseline transferrin saturation, and quantitative left ventricular ejection fraction (LVEF), 33 (49%) and 14 (21%) were iron deficient and sufficient, respectively, and 21 (31%) indeterminant. LVEF was reduced to 23.6 ± 12.1% from 32.9 ± 16.8% in iron deficiency and sufficiency, respectively (P = .04), without a significant difference in hemoglobin. After stratification by New York Heart Association classification, in advanced class IV, hemoglobin was reduced to 10.9 ± 1.3 g/dL vs 12.7 ± 2.0 g/dL in iron deficiency and sufficiency, respectively (P = .01), without a significant difference in LVEF.

CONCLUSIONS

In this single-center study, iron deficiency was not monitored in most children with chronic heart failure. In pediatric dilated cardiomyopathy-induced heart failure, absolute iron deficiency was prevalent and associated with clinically consequential and possibly correctable decreases in cardiac function and hemoglobin concentration.

Intravenous Iron for Heart Failure: Updated Systematic Review and Meta-Analysis

While the administration of intravenous (IV) iron to those with heart failure has been implicated to be associated with a possible reduction in hospitalizations and improvement in symptoms, a recent large multicenter trial only showed modest benefits in reducing hospitalization, necessitating the updated systematic review. We conducted a systematic review and meta-analysis, searching the MEDLINE and EMBASE database until January 9, 2023. Outcomes included total heart failure hospitalizations, first heart failure hospitalization, six-minute walk test (6MWT) distance, and incidence of infection. There were 13 studies with 3410 participants (1,790 with IV iron). Pooled analysis that reported the incidence of cardiovascular death showed that patients with IV iron did not have significantly lower odds of cardiovascular death or first heart failure hospitalization. In contrast, those who received IV iron had significantly lower total heart failure hospitalization (pooled odds ratio (OR) 0.63, 95% confidence interval (CI) 0.44-0.90, I2 59.0%, P = .017) and a composite of cardiovascular death and first heart failure hospitalization (pooled OR 0.55, 95% CI 0.47-0.64, I2 0%, P = .656). While the efficacy is modest, IV iron therapy could be associated with reduced hospitalization for heart failure without significant adverse events.

Comparison of different intravenous iron preparations in terms of total oxidant and total antioxidant status, single center data

Iron deficiency anemia is the most common and preventable cause of anemia. Oral and parenteral iron preparations can be used for treatment. There are some concerns about the effect on oxidative stress of parenteral preparations. In this study, we aimed to investigate the effect of ferric carboxymaltose and iron sucrose on short- and long-term oxidant-antioxidant status. The study was designed as a prospective, single-center, observational study. Patients diagnosed with iron deficiency anemia and receiving intravenous iron therapy were included. Patients were divided into 3 groups as those receiving 1000 mg iron sucrose, 1000 mg ferric carboxymaltose, and 1500 mg ferric carboxymaltose. Blood samples were collected for blood tests before treatment, at the 1st hour of the first infusion, and at the 1st month of follow-up. The total oxidant and total antioxidant status were analyzed to evaluate oxidative stress and antioxidant status. Fifty-eight patients are included. Nineteen patients received iron sucrose 1000 mg (G1), 21 patients received ferric carboxymaltose 1000 mg (G2), and 18 patients received ferric carboxymaltose 1500 mg (G3). First hour total antioxidant status was higher in the iron sucrose group than in the ferric carboxymaltose group [G1 and G2 (p = 0.027), G1 and G3 (p = 0.004)]. At the 1st hour, total oxidant status was higher in iron sucrose group than in ferric carboxymaltose group [G1 and G2 (p = 0.016), G1 and G3 (p = 0.011)]. There was no difference in total oxidant and antioxidant stress between the three treatment groups at the 1st month evaluation [p: 0.19 and p: 0.12]. Total oxidant and antioxidant status in iron sucrose and ferric carboxymaltose formulations were found to be higher in the iron sucrose group in the acute period at the 1st hour after infusion. There was no significant difference between antioxidant and oxidant total status in all three treatment groups at the 1st month of long-term control. The fact that total oxidant status was lower in the ferric carboxymaltose group containing high-dose treatment compared to iron sucrose according to the 1st hour change showed that high-dose iron did not significantly affect oxidant stress in the short term. In addition, long-term oxidant stress evaluation at the 1st month did not show any difference between iron preparations. In conclusion, it has been shown that high-dose intravenous iron therapy, which is easier to use in clinical practice, has no effect on the oxidant-antioxidant system.

Modulation of the nitric oxide/cGMP pathway in cardiac contraction and relaxation: Potential role in heart failure treatment

Evidence exists that heart failure (HF) has an overall impact of 1-2 % in the global population being often associated with comorbidities that contribute to increased disease prevalence, hospitalization, and mortality. Recent advances in pharmacological approaches have significantly improved clinical outcomes for patients with vascular injury and HF. Nevertheless, there remains an unmet need to clarify the crucial role of nitric oxide/cyclic guanosine 3',5'-monophosphate (NO/cGMP) signalling in cardiac contraction and relaxation, to better identify the key mechanisms involved in the pathophysiology of myocardial dysfunction both with reduced (HFrEF) as well as preserved ejection fraction (HFpEF). Indeed, NO signalling plays a crucial role in cardiovascular homeostasis and its dysregulation induces a significant increase in oxidative and nitrosative stress, producing anatomical and physiological cardiac alterations that can lead to heart failure. The present review aims to examine the molecular mechanisms involved in the bioavailability of NO and its modulation of downstream pathways. In particular, we focus on the main therapeutic targets and emphasize the recent evidence of preclinical and clinical studies, describing the different emerging therapeutic strategies developed to counteract NO impaired signalling and cardiovascular disease (CVD) development.