Cardiac iron across different transfusion-dependent diseases

Ironing out the details of ferroptosis

Ferroptosis, spurred by excess labile iron and lipid peroxidation, is implicated in various diseases. Advances have been made in comprehending the lipid-peroxidation side of ferroptosis, but the exact role of iron in driving ferroptosis remains unknown. Although iron overload is characterized in multiple disease states, the potential role of ferroptosis within them remains undefined. This overview focuses on the 'ferro' side of ferroptosis, highlighting iron dysregulation in human diseases and potential therapeutic strategies targeting iron regulation and metabolism.

Low Vitamin D Levels Are Associated with Increased Cardiac Iron Uptake in Beta-Thalassemia Major

We evaluated the association of vitamin D and parathormone (PTH) levels with cardiac iron and function in beta-thalassemia major (β-TM) patients. Two-hundred and seventy-eight TM patients (39.04 ± 8.58 years, 56.8% females) underwent magnetic resonance imaging for the assessment of iron overload (T2* technique), biventricular function parameters (cine images), and replacement myocardial fibrosis (late gadolinium enhancement technique). Vitamin D levels were deficient (<20 ng/dL) in 107 (38.5%) patients, insufficient (20-30 ng/dL) in 96 (34.5%) patients, and sufficient (≥30 ng/dL) in 75 (27.0%) patients. Deficient vitamin D patients had a significantly higher frequency of myocardial iron overload (MIO; global heart T2* < 20 ms) than patients with sufficient and insufficient vitamin D levels and a significantly higher left ventricular end-diastolic volume index and mass index than patients with sufficient vitamin D levels. PTH was not associated with cardiac iron, function, or fibrosis. In the multivariate regression analysis, vitamin D, serum ferritin, and pancreatic iron levels were the strongest predictors of global heart T2* values. In receiver operating characteristic curve analysis, a vitamin D level ≤ 17.3 ng/dL predicted MIO with a sensitivity of 81.5% and a specificity of 75.3% (p < 0.0001). In TM, the periodic and regular assessment of vitamin D levels can be beneficial for the prevention of cardiac iron accumulation and subsequent overt dysfunction.

Ferroptosis inhibitor improves cardiac function more effectively than inhibitors of apoptosis and necroptosis through cardiac mitochondrial protection in rats with iron-overloaded cardiomyopathy

Iron overload cardiomyopathy (IOC) is the leading cause of death in cases of iron overload in patients. Previous studies demonstrated that iron overload led to cardiomyocyte dysfunction and death through multiple pathways including apoptosis, necroptosis and ferroptosis. However, the dominant cell death pathway in the iron-overloaded heart needs clarification. We tested the hypothesis that ferroptosis, an iron-dependent cell death, plays a dominant role in IOC, and ferroptosis inhibitor exerts greater efficacy than inhibitors of apoptosis and necroptosis on improving cardiac function in iron-overloaded rats. Iron dextran was injected intraperitoneally into male Wistar rats for four weeks to induce iron overload. Then, the rats were divided into 5 groups: treated with vehicle, apoptosis inhibitor (z-VAD-FMK), necroptosis inhibitor (Necrostatin-1), ferroptosis inhibitor (Ferrostatin-1) or iron chelator (deferoxamine) for 2 weeks. Cardiac function, mitochondrial function, apoptosis, necroptosis and ferroptosis were determined. The increased expression of apoptosis-, necroptosis- and ferroptosis-related proteins, were associated with impaired cardiac and mitochondrial function in iron-overloaded rats. All cell death inhibitors attenuated cardiac apoptosis, necroptosis and ferroptosis in iron-overloaded rats. Ferrostatin-1 was more effective than the other drugs in diminishing mitochondrial dysfunction and Bax/Bcl-2 ratio. Moreover, both Ferrostatin-1 and deferoxamine reversed iron overload-induced cardiac dysfunction as indicated by restored left ventricular ejection fraction and E/A ratio, whereas z-VAD-FMK and Necrostatin-1 only partially improved this parameter. These results indicated that ferroptosis could be the predominant form of cardiomyocyte death in IOC, and that inhibiting ferroptosis might be a potential novel treatment for IOC.

Inflammation, dysregulated iron metabolism, and cardiovascular disease

Iron is an essential trace element associated with both pathologic deficiency and toxic overload. Thus, systemic and cell iron metabolism are highly controlled processes regulated by protein expression and localization, as well as turnover, through the action of cytokines and iron status. Iron metabolism in the heart is challenging because both iron overload and deficiency are associated with cardiac disease. Also associated with cardiovascular disease is inflammation, as many cardiac diseases are caused by or include an inflammatory component. In addition, iron metabolism and inflammation are closely linked. Hepcidin, the master regulator of systemic iron metabolism, is induced by the cytokine IL-6 and as such is among the acute phase proteins secreted by the liver as part of the inflammatory response. In an inflammatory state, systemic iron homeostasis is dysregulated, commonly resulting in hypoferremia, or low serum iron. Less well characterized is cardiac iron metabolism in general, and even less is known about how inflammation impacts heart iron handling. This review highlights what is known with respect to iron metabolism in the heart. Expression of iron metabolism-related proteins and processes of iron uptake and efflux in these cell types are outlined. Evidence for the strong co-morbid relationship between inflammation and cardiac disease is also reviewed. Known connections between inflammatory processes and iron metabolism in the heart are discussed with the goal of linking inflammation and iron metabolism in this tissue, a connection that has been relatively under-appreciated as a component of heart function in an inflammatory state. Therapeutic options connecting inflammation and iron balance are emphasized, with the main goal of this review being to bring attention to alterations in iron balance as a component of inflammatory diseases of the cardiovascular system.

Prognostic value of multiparametric cardiac magnetic resonance in sickle cell patients

The aim of this multicenter study was to prospectively assess the predictive value of multiparametric cardiac magnetic resonance (CMR) for cardiovascular complications in sickle cell disease (SCD) patients. Among all patients with hemoglobinopathies consecutively enrolled in the Myocardial Iron Overload in Thalassemia (MIOT) Network, we selected 102 SCD patients (34.38 ± 12.67 years, 49 females). Myocardial iron overload (MIO) was measured by the multislice multiecho T2* technique. Atrial dimensions and biventricular function parameters were quantified by cine images. Late gadolinium enhancement (LGE) images were acquired to detect focal myocardial fibrosis. At baseline CMR, only two patients had significant MIO (global heart T2* < 20 ms). During a mean follow-up of 63.01 ± 24.95 months, 11 cardiovascular events (10.8%) were registered: 3 pulmonary hypertension, 2 supraventricular arrhythmias, 1 heart failure, 1 death for heart failure, 1 pulmonary embolism, 1 peripheral vascular disease, 1 transient ischemic attack, and 1 death after acute chest syndrome. In the multivariate analysis, the independent CMR predictors of cardiovascular events were left ventricular (LV) ejection fraction (hazard ratio-HR = 0.88; p = 0.025) and right ventricular (RV) mass index (HR = 1.09; p = 0.047). According to the receiver-operating characteristic curve analysis for adverse events, an LV ejection fraction < 58.9% and an RV mass index > 31 g/m² were optimal cut-off values. Reduced left ventricular ejection fraction and increased right ventricular mass index showed a significant prognostic value in patients with SCD. Our data seem to suggest that CMR may be added as a screening tool for identifying SCD patients at high risk for cardiopulmonary and vascular diseases.

Cardiovascular Complications in β-Thalassemia: Getting to the Heart of It

Beta thalassemia is an inherited disorder resulting in abnormal or decreased production of hemoglobin, leading to hemolysis and chronic anemia. The long-term complications can affect multiple organ systems, namely the liver, heart, and endocrine. Myocardial iron overload is a common finding in β-thalassemia. As a result, different cardiovascular complications in the form of cardiomyopathy, pulmonary hypertension, arrhythmias, and vasculopathies can occur, and in extreme cases, sudden cardiac death. Each of these complications pertains to underlying etiologies and risk factors, which highlights the importance of early diagnosis and prevention. In this review, we will discuss different types of cardiovascular complications that can manifest in patients with β-thalassemia, in addition to the current diagnostic modalities, preventive and treatment modalities for these complications.

Quantitative Analysis of Liver Iron Deposition Based on Dual-Energy CT in Thalassemia Patients

Background

To explore the feasibility and accuracy of liver iron deposition based on dual-energy CT in thalassemia patients.

Materials and methods

105 thalassemia patients were examined with dual-energy CT and MR liver scanning. Dual-energy CT was performed to measure CT values on 80kVp, 140kVp, and virtual iron content (VIC) imaging; ΔH was figured out by the difference in CT values between 80kVp and 140kVp. Using the liver iron concentration (LIC) obtained by FerriScan as a gold standard, the correlation between CT measurements and LIC was evaluated. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic performance for dual-energy CT in liver iron quantification and stratification.

Results

The correlation analysis between CT measurements and LIC showed that 80kVp, 140kVp, VIC, and ΔH all had a high positive correlation with LIC (P<0.001). The correlation analysis among different degree groups of VIC, ΔH, and LIC showed that the normal, moderate, and severe groups of VIC and ΔH had moderate or high positive correlations with that of LIC (P<0.01), but the mild group had no correlation (P>0.05). ROC analysis revealed that the corresponding optimal cutoff value of VIC was -2.8, 6.3,11.9 HU (corresponds to 3.2,7.0,15.0 mg/g dry weight) respectively, while the ΔH were 5.1, 8.4, 17.8HU, respectively. The area under the receiver operating characteristic curves (AUCs) for both VIC and ΔH increased with LIC thresholds.

Conclusion

Dual-energy CT can accurately quantify and stratify liver iron deposition, contributing to predicting the status of liver iron deposition in thalassemia patients.

Gene Editing for Sickle Cell Disease and Transfusion Dependent Thalassemias- A cure within reach

Sickle cell disease (SCD) is associated with significant morbidity and shortened life expectancy. Similarly, patients with transfusion dependent beta thalassemia (TdT) require life-long transfusion therapy, chelation therapy and significant organ dysfunction. Allogeneic transplantation from a matched family donor provided the only curative option for patients with SCD and TdT. Unfortunately, less than 20% of patients have a fully matched related donor and results using unrelated donor transplant were associated with high rate of complications. Ex vivo gene therapy through globin gene addition has been investigated extensively and recent encouraging preliminary data resulted in regulatory approval in patients with TdT. Recent improvements in our understanding of the molecular pathways controlling erythropoiesis and globin switching from fetal hemoglobin to adult hemoglobin offer a new and exciting therapeutic options. Rapid and substantial advances in genome editing tools using CRISPR/Cas9, have raised the possibility of genetic editing and correction in patient derived hematopoietic stem and progenitor cells. We will review results of gene editing approach that can induce fetal hemoglobin production in patients with SCD and TdT.

Magnetic resonance imaging T2* of the pancreas value using an online software tool and correlate with T2* value of myocardium and liver among patients with transfusion-dependent thalassemia major

Objective

Patients with thalassemia major do require lifetime blood transfusions that eventually result in iron accumulation in different organs. We described the usefulness of using magnetic resonance imaging (MRI) T2^*imaging values for the evaluation of pancreatic iron load in these patients, and we correlated it with MRI T2^* haemosiderosis of the myocardium and liver that has been recognized as a non-invasive assessment of iron overload among patients with thalassemia major.

Materials and methods

We conducted a cross-sectional study on 39 patients with thalassemia major in one of the tertiary university hospitals for a 1-year period. Demographic data were collected from the patient's history. MRI T2^* of the pancreas, liver, and heart were executed on all patients in the same setting. Objective values of iron overload in these organs were obtained using the MRI post-processing software from online software.

Results

A total of 32 (82.1%) patients had pancreatic iron overload including 2 patients (5.1%) with severe iron overload and 15 patients (38.5%) with moderate and mild iron overload, respectively. Nine patients (23.1%) had myocardial iron overload, which included 3 patients (7.7%) who had severe cardiac haemosiderosis. Notably, 37 patients (94.9%) had liver iron overload, which included 15 patients (38.5%) who had severe liver haemosiderosis. There was a moderate positive correlation between the relaxation time of the pancreas and heart haemosiderosis (r = 0.504, P < 0.001). No significant correlation was found between the relaxation time of the pancreas with the liver and the heart with the liver.

Conclusion

Pancreatic haemosiderosis precedes cardiac haemosiderosis, which establishes a basis for initiating earlier iron chelation therapy to patients with thalassemia major.

Iron overload disorders

Iron overload disorders represent a variety of conditions that lead to increased total body iron stores and resultant end-organ damage. An elevated ferritin and transferrin-iron saturation can be commonly encountered in the evaluation of elevated liver enzymes. Confirmatory homeostatic iron regulator (HFE) genetic testing for C282Y and H63D, mutations most encountered in hereditary hemochromatosis, should be pursued in evaluation of hyperferritinemia. Magnetic resonance imaging with quantitative assessment of iron content or liver biopsy (especially if liver disease is a cause of iron overload) should be used as appropriate. A secondary cause for iron overload should be considered if HFE genetic testing is negative for the C282Y homozygous or C282Y/H63D compound heterozygous mutations. Differential diagnosis of secondary iron overload includes hematologic disorders, iatrogenic causes, or chronic liver diseases. More common hematologic disorders include thalassemia syndromes, myelodysplastic syndrome, myelofibrosis, sideroblastic anemias, sickle cell disease, or pyruvate kinase deficiency. If iron overload has been excluded, evaluation for causes of hyperferritinemia should be pursued. Causes of hyperferritinemia include chronic liver disease, malignancy, infections, kidney failure, and rheumatic conditions, such as adult-onset Still's disease or hemophagocytic lymphohistiocytosis. In this review, we describe the diagnostic testing of patients with suspected hereditary hemochromatosis, the evaluation of patients with elevated serum ferritin levels, and signs of secondary overload and treatment options for those with secondary iron overload.

Studying the some biochemical parameters for thalassemia patients in AL-Najaf province

The current study aims to study some biochemical indicators for thalassemia patients in the Najaf governorate, and the study included 25 patients with major beta thalassemia during the period from November 2019 to February 2020 and their ages ranged between (2 - 65) years and 15 healthy people who arenot He had genetic blood diseases and their ages ranged between (2-65) years. The results of the study showed that there are in some biochemical indicators, as there was a significant increase in the level of the enzyme of liver function  ALT that was the focus in patients 23.74 ± 29.53 U\L and in healthy people it was 4.61 ± 11.67U\L Also, the creatinine concentration patients 9.92 ± 26.08 mmol\L and in healthy was, 68.06 ± 51.54 mmol\L, Except for urea, we notice that there was a decrease in its concentration in patients 0.89 ± 3.96 mmol\L and in healthy was 1.03 ± 2.36 mmol\L, There was an increase in the concentration of iron in the blood in patients 382.05 ±64.37 Umol\L And in healthy was 9.48 ± 61.36 Umol\L, as well as a decrease in the concentration of glucose in patients and an increase in healthy people

Iron overload cardiomyopathy: Using the latest evidence to inform future applications

Iron overload can be the result of either dysregulated iron metabolism in the case of hereditary hemochromatosis or repeated blood transfusions in the case of secondary hemochromatosis (e.g. in β-thalassemia and sickle cell anemia patients). Under iron overload conditions, transferrin (Tf) saturation leads to an increase in non-Tf bound iron which can result in the generation of reactive oxygen species (ROS). These excess ROS can damage cellular components, resulting in the dysfunction of vital organs including iron overload cardiomyopathy (IOC). Multiple studies have demonstrated that L-type and T-type calcium channels are the main routes for iron uptake in the heart, and that calcium channel blockers, given either individually or in combination with standard iron chelators, confer cardioprotective effects under iron overload conditions. Treatment with antioxidants may also provide therapeutic benefits. Interestingly, recent studies have suggested that mitochondrial dynamics and regulated cell death (RCD) pathways are potential targets for pharmacological interventions against iron-induced cardiomyocyte injury. In this review, the potential therapeutic roles of iron chelators, antioxidants, iron uptake/metabolism modulators, mitochondrial dynamics modulators, and inhibitors of RCD pathways in IOC are summarized and discussed.

Triad role of hepcidin, ferroportin, and Nrf2 in cardiac iron metabolism: From health to disease

Iron is an essential trace element required for several vital physiological and developmental processes, including erythropoiesis, bone, and neuronal development. Iron metabolism and oxygen homeostasis are interlinked to perform a vital role in the functionality of the heart. The metabolic machinery of the heart utilizes almost 90 % of oxygen through the electron transport chain. To handle this tremendous level of oxygen, the iron metabolism in the heart is utmost crucial. Iron availability to the heart is therefore tightly regulated by (i) the hepcidin/ferroportin axis, which controls dietary iron absorption, storage, and recycling, and (ii) iron regulatory proteins 1 and 2 (IRP1/2) via hypoxia inducible factor 1 (HIF1) pathway. Despite iron being vital to the heart, recent investigations have demonstrated that iron imbalance is a common manifestation in conditions of heart failure (HF), since free iron readily transforms between Fe²⁺ and Fe³⁺via the Fenton reaction, leading to reactive oxygen species (ROS) production and oxidative damage. Therefore, to combat iron-mediated oxidative stress, targeting Nrf2/ARE antioxidant signaling is rational. The involvement of Nrf2 in regulating several genes engaged in heme synthesis, iron storage, and iron export is beginning to be uncovered. Consequently, it is possible that Nrf2/hepcidin/ferroportin might act as an epicenter connecting iron metabolism to redox alterations. However, the mechanism bridging the two remains obscure. In this review, we tried to summarize the contemporary insight of how cardiomyocytes regulate intracellular iron levels and discussed the mechanisms linking cardiac dysfunction with iron imbalance. Further, we emphasized the impact of Nrf2 on the interplay between systemic/cardiac iron control in the context of heart disease, particularly in myocardial ischemia and HF.

A Novel Insight Into the Fate of Cardiomyocytes in Ischemia-Reperfusion Injury: From Iron Metabolism to Ferroptosis

Ischemia-reperfusion injury (IRI), critically involved in the pathology of reperfusion therapy for myocardial infarction, is closely related to oxidative stress the inflammatory response, and disturbances in energy metabolism. Emerging evidence shows that metabolic imbalances of iron participate in the pathophysiological process of cardiomyocyte IRI [also termed as myocardial ischemia-reperfusion injury (MIRI)]. Iron is an essential mineral required for vital physiological functions, including cellular respiration, lipid and oxygen metabolism, and protein synthesis. Nevertheless, cardiomyocyte homeostasis and viability are inclined to be jeopardized by iron-induced toxicity under pathological conditions, which is defined as ferroptosis. Upon the occurrence of IRI, excessive iron is transported into cells that drive cardiomyocytes more vulnerable to ferroptosis by the accumulation of reactive oxygen species (ROS) through Fenton reaction and Haber–Weiss reaction. The increased ROS production in ferroptosis correspondingly leads cardiomyocytes to become more sensitive to oxidative stress under the exposure of excess iron. Therefore, ferroptosis might play an important role in the pathogenic progression of MIRI, and precisely targeting ferroptosis mechanisms may be a promising therapeutic option to revert myocardial remodeling. Notably, targeting inhibitors are expected to prevent MIRI deterioration by suppressing cardiomyocyte ferroptosis. Here, we review the pathophysiological alterations from iron homeostasis to ferroptosis together with potential pathways regarding ferroptosis secondary to cardiovascular IRI. We also provide a comprehensive analysis of ferroptosis inhibitors and initiators, as well as regulatory genes involved in the setting of MIRI.

Cardiac MR images of thalassemia major patients with myocardial iron overload: a data note

OBJECTIVE

Patients with thalassemia major (TM) have the highest mortality rate due to heart failure induced by myocardial iron overload. However, T2* weighted MR imaging is currently a gold standard approach for measuring iron overload. Examining ventricular volumes with magnetic resonance imaging (MR imaging) and measuring myocardial iron overload in TM patients allows for an early prediction of heart failure. This dataset includes cardiac MR images of TM patients and the control group with clinical and echocardiographic data. This dataset may be useful to researchers investigating myocardial iron overload. This dataset can also be used for medical image processing applications, such as ventricle segmentation.

DATA DESCRIPTION

This study provides open-source cardiac MR images of 50 subjects and clinical and echocardiographic data. From February 2016 to January 2019, all images and clinical data were obtained from the MRI department of a general hospital in Mashhad, Iran. All the images are 16-bit gray-scale and stored in DICOM format. All patient-specific information is removed from image headers to preserve patient privacy. In addition, all images associated with each subject are compressed and saved in the RAR format.

Role of Iron in the Molecular Pathogenesis of Diseases and Therapeutic Opportunities

Iron is an essential mineral that serves as a prosthetic group for a variety of proteins involved in vital cellular processes. The iron economy within humans is highly conserved in that there is no proper iron excretion pathway. Therefore, iron homeostasis is highly evolved to coordinate iron acquisition, storage, transport, and recycling efficiently. A disturbance in this state can result in excess iron burden in which an ensuing iron-mediated generation of reactive oxygen species imparts widespread oxidative damage to proteins, lipids, and DNA. On the contrary, problems in iron deficiency either due to genetic or nutritional causes can lead to a number of iron deficiency disorders. Iron chelation strategies have been in the works since the early 1900s, and they still remain the most viable therapeutic approach to mitigate the toxic side effects of excess iron. Intense investigations on improving the efficacy of chelation strategies while being well tolerated and accepted by patients have been a particular focus for many researchers over the past 30 years. Moreover, recent advances in our understanding on the role of iron in the pathogenesis of different diseases (both in iron overload and iron deficiency conditions) motivate the need to develop new therapeutics. We summarized recent investigations into the role of iron in health and disease conditions, iron chelation, and iron delivery strategies. Information regarding small molecule as well as macromolecular approaches and how they are employed within different disease pathogenesis such as primary and secondary iron overload diseases, cancer, diabetes, neurodegenerative diseases, infections, and in iron deficiency is provided.

Advancement of echocardiography for surveillance of iron overload cardiomyopathy: comparison to cardiac magnetic resonance imaging

The prevalence of iron overload cardiomyopathy (IOC) is increasing. Patients with transfusion-dependent anemias or conditions associated with increased iron absorption over time are at a significant risk for the development of iron-overloaded states such as IOC. Current guidelines regarding the diagnostic evaluation and follow-up of patients at risk for IOC exist, and are composed of multiple components, including such as echocardiography, genetic testing, magnetic resonance imaging of liver, and cardiac magnetic resonance imaging (CMR). While these are considered reliable for the evaluation of patients at risk for an iron-overloaded state, there is an access challenge associated with initial and serial CMR scanning in this patient population. Furthermore, there are other limiting factors, such as patient characteristics that may preclude the use of CMR as a viable diagnostic imaging modality for these patients. On the other hand, recent evidence in the literature suggests that transthoracic echocardiography, which has had significant technological advances, can equal or even outperform CMR to identify cardiac functional abnormalities such as subclinical left ventricular strain and left atrial functional abnormalities in iron overload conditions. Therefore, there is a potential role of more frequent use of echocardiography for surveillance of the development of IOC. Our purpose with this narrative review is to describe recent advances in echocardiography and propose a potential increased use of echocardiography in the surveillance of the development of IOC.

Moxibustion with deferasirox results in safe, accelerated, and sustained cardiac iron chelation for a young Diamond Blackfan Anemia patient: An integrative case report

Diamond Blackfan Anemia (DBA) is a rare blood disorder of bone marrow failure typically identified in the first year of life. Due to treatment limitations, nearly all DBA patients are reliant upon chronic red cell infusion for some period of their lives. Repeat blood transfusion invariably leads to iron overload, which creates significant and life-threatening side effects. In this case report, a female child of 2 years and 8 months with DBA was diagnosed via T2* MRI imaging with potentially emergent levels of cardiac iron overload as a result of chronic red cell infusion. According to Chinese, Japanese, and integrative medicine principles, moxibustion was applied externally in conjunction with the prescribed oral chelation agent, deferasirox (DFX), over a period of six months. Analysis of repeat imaging at six months showed complete removal of cardiac iron and a one-third decrease in hepatic iron. In addition, there was no evidence of known risks to high-dose chelation, including renal, aural, or ocular damage. Follow-up examination two years after initial imaging showed no evidence of cardiac iron deposition with hepatic iron levels below minimum levels recommended for chelation despite the medical necessity of continued red cell infusion. This case study suggests that an integrative medical approach combining DFX with moxibustion may safely accelerate and sustain iron chelation for transfusion-dependent DBA patients. Recommendations for a successful approach to integrative iron chelation are provided in the case discussion.

Thalassemia in the emergency department: special considerations for a rare disease

Thalassemia is characterized by a defect in the synthesis of one or more of the globin subunits of hemoglobin. This defect results in imbalance in the α/β-globin chain ratio, ineffective erythropoiesis, chronic hemolytic anemia, and iron overload. With advances in diagnosis, treatment, and transfusion support, the prognosis of patients with thalassemia has improved over the past few decades. An increasing number of patients with thalassemia is living with long-term complications, including cardiomyopathy, chronic liver disease, endocrinopathy, and infections. In this paper, we review common complications that bring the patient with thalassemia to urgent or emergent medical attention. We also discuss the aspects of emergency care that are most relevant while caring for the patient with thalassemia in the emergency department.

Rosette Trajectories Enable Ungated, Motion-Robust, Simultaneous Cardiac and Liver T2 * Iron Assessment

BACKGROUND

Quantitative T₂ * MRI is the standard of care for the assessment of iron overload. However, patient motion corrupts T₂ * estimates.

PURPOSE

To develop and evaluate a motion-robust, simultaneous cardiac and liver T₂ * imaging approach using non-Cartesian, rosette sampling and a model-based reconstruction as compared to clinical-standard Cartesian MRI.

STUDY TYPE

Prospective.

PHANTOM/POPULATION

Six ferumoxytol-containing phantoms (26-288 μg/mL). Eight healthy subjects and 18 patients referred for clinically indicated iron overload assessment.

FIELD STRENGTH/SEQUENCE

1.5T, 2D Cartesian and rosette gradient echo (GRE) ASSESSMENT: GRE T₂ * values were validated in ferumoxytol phantoms. In healthy subjects, test-retest and spatial coefficient of variation (CoV) analysis was performed during three breathing conditions. Cartesian and rosette T₂ * were compared using correlation and Bland-Altman analysis. Images were rated by three experienced radiologists on a 5-point scale.

STATISTICAL TESTS

Linear regression, analysis of variance (ANOVA), and paired Student's t-testing were used to compare reproducibility and variability metrics in Cartesian and rosette scans. The Wilcoxon rank test was used to assess reader score comparisons and reader reliability was measured using intraclass correlation analysis.

RESULTS

Rosette R2* (1/T₂ *) was linearly correlated with ferumoxytol concentration (r² = 1.00) and not significantly different than Cartesian values (P = 0.16). During breath-holding, ungated rosette liver and heart T₂ * had lower spatial CoV (liver: 18.4 ± 9.3% Cartesian, 8.8% ± 3.4% rosette, P = 0.02, heart: 37.7% ± 14.3% Cartesian, 13.4% ± 1.7% rosette, P = 0.001) and higher-quality scores (liver: 3.3 [3.0-3.6] Cartesian, 4.7 [4.1-4.9] rosette, P = 0.005, heart: 3.0 [2.3-3] Cartesian, 4.5 [3.8-5.0] rosette, P = 0.005) compared to Cartesian values. During free-breathing and failed breath-holding, Cartesian images had very poor to average image quality with significant artifacts, whereas rosette remained very good, with minimal artifacts (P = 0.001).

DATA CONCLUSION

Rosette k-sampling with a model-based reconstruction offers a clinically useful motion-robust T₂ * mapping approach for iron quantification. J. MAGN. RESON. IMAGING 2020;52:1688-1698.

Free-breathing T2* mapping for MR myocardial iron assessment at 3 T

BACKGROUND

Timely diagnosis of cardiac iron overload is important for children with transfusion-dependent anaemias and requires modern measure methods. Nowadays, myocardial iron quantification is performed by magnetic resonance (MR) breath-hold techniques, sensitive to respiratory motion and unfeasible in patients who are unable to hold their breath. Free-breathing T2* mapping sequences would allow to scan children who cannot hold their breath for a specified duration. Our aim was to test a free-breathing T2* mapping sequence, based on motion correction by multiple signal accumulation technique.

METHODS

We used an electrocardiographically gated T2* mapping sequence based on multiple gradient echo at 3-T in 37 paediatric patients with haematologic disorders aged from 2 to 16. We compared T2* values of myocardium and signal-to-noise ratio of this new sequence with standard breath-holding T2* mapping sequence. T2* values were measured in the interventricular septum for both methods in studies with adequate image quality.

RESULTS

All children were scanned without complications. Five patients were excluded from analysis because of the presence of respiratory artefacts on the T2* images with breath-holding technique due to patient's inability to hold their breath. Breath-holding T2* was 19.5 ± 7.7 ms (mean ± standard deviation), free-breathing T2* was 19.4 ± 7.6 ms, with positive correlation (r = 0.99, R2 = 0.98; p < 0.001). The free-breathing sequence had a higher signal-to-noise ratio (median 212.8, interquartile range 148.5-566.5) than the breath-holding sequence (112.6, 71.1-334.1) (p = 0.03).

CONCLUSION

A free-breathing sequence provided accurate measurement of myocardial T2* values in children.

Cardiac and hepatic siderosis in myelodysplastic syndrome, thalassemia and diverse causes of transfusion-dependent anemia: the TIMES study

Supplemental Digital Content is available in the text

The significant morbidity and mortality associated with iron overload can be reduced by effective iron chelation. Magnetic resonance imaging (MRI) provides accurate and reproducible iron load assessment. The aim of this epidemiological study was to assess the prevalence and severity of cardiac and hepatic siderosis by MRI and to evaluate the impact of MRI on clinical management in patients with transfusion-dependent anemia and non-transfusion-dependent thalassemia (NTDT). We enrolled 243 patients with myelodysplastic syndromes (MDS), thalassemia major (TM), NTDT or other chronic anemia. Overall, 10% and 48% had cardiac and hepatic siderosis, respectively. Mean liver iron concentration (LIC) was above target range in all groups; mean myocardial T2^∗ was normal. Hepatic siderosis was more prevalent than myocardial siderosis in patients with MDS, occurring in 54.4% and 4.4% of patients, respectively. As also observed in patients with NTDT or other anemia, hepatic siderosis was present in a large proportion of MDS patients who were chelation naïve (57.7%), as well as in patients receiving iron chelation therapy (ICT) (52.4%), despite a lower transfusion load compared with TM. Correlation between LIC and serum ferritin was observed across diseases; however, not all patients requiring ICT could be identified with serum ferritin alone, as serum ferritin underestimated LIC in 4.4% and overestimated LIC in 7.5% of patients. Exploratory analyses showed serum ferritin thresholds for liver siderosis detected by MRI at approximately 300 ng/mL higher in MDS than in TM. Most patients reported low–medium adherence to ICT; MRI assessment led to change in ICT in 46% of evaluable patients, including 52% of MDS patients. Accurate organ iron monitoring by MRI facilitated appropriate initiation of chelation, dose optimization and clinical decision making.

Trial registration: ClinicalTrials.gov: NCT01736540.

Long-term improvement in cardiac magnetic resonance in β-thalassemia major patients treated with deferasirox extends to patients with abnormal baseline cardiac function

The management of iron overload in thalassemia has changed dramatically since the implementation of magnetic resonance imaging, which allows detection of preclinical iron overload and prevention of clinical complications. This study evaluated the effect of deferasirox (DFX), the newest once-daily oral chelator, on cardiac function, iron overload and cardiovascular events over a longer follow up in a "real world" setting. Longitudinal changes in cardiac magnetic resonance T2*, cardiac function parameters and cardiovascular clinical events were assessed in a cohort of 98 TM patients exposed to DFX for a mean of 6.9 years (range 1.8-11.6 years). No cardiac death or incident heart failure occurred. Cardiac T2* significantly increased (+2.6 ± 11.9 msec; P = 0.035) in the whole population, with a significantly greater increase (+11.6 ± 15.5 msec, P = 0.019) in patients with cardiac iron overload (T2* <20 ms). A significant improvement in left-ventricular ejection fraction (LVEF) (from 50.6 ± 6 to 60.2 ± 5; P = 0.001) was observed in 11 (84.6%) out of 13 patients who normalized cardiac function (LVEF >56%). Arrhythmias were the most frequent cardiac adverse event noted but none led to DFX discontinuation. Our data indicate that DFX is effective in maintaining cardiac iron level in the normal range and in improving cardiac iron overload. No heart failure or cardiac death was reported over this longer observation up to 12 years. For the first time, a DFX-induced improvement in LVEF was observed in a subgroup of patients with abnormal cardiac function at baseline, a preliminary observation which deserves further evaluation.

Cardiac iron overload following liver transplantation in patients without hereditary hemochromatosis or severe hepatic iron deposition

BACKGROUND

Cardiac iron overload following liver transplantation in patients without hemochromatosis but with severe hepatic iron deposition has been reported to result in heart failure and/or death in case reports and small case series. However, the frequency and causes of cardiac iron overload following liver transplantation and its relationship to cardiac dysfunction in patients without severe hepatic iron deposition are unclear.

METHODS

The primary inclusion criteria for this study were liver transplantation followed by autopsy or cardiac transplantation within 1 year. Cases of known hemochromatosis were excluded. Iron stains were performed on left ventricular myocardium from either the autopsy or surgically resected heart, as well as the surgically resected liver.

RESULTS

Nineteen cases met the study criteria: 18 autopsies and 1 case of cardiac transplantation. None of the resected livers evaluated showed severe iron deposition. Myocardial iron deposition was identified in 7 (37%) of the cases. The presence of myocardial iron deposition was not significantly associated with the grade of hepatic iron deposition, or the pre-liver transplantation serum iron or ferritin levels. However, in the patients with myocardial iron deposition, there were trends toward higher pretransplant transferrin saturation (TSAT) and more units of red blood cells transfused (uRBC). The product of the TSAT multiplied by the uRBC was significantly greater in the patients with myocardial iron deposition [4700 (3100-9800) vs. 680 (400-2300), median (interquartile range), P=.003]. New reduced left ventricular ejection fraction (<50%) following liver transplantation occurred in four of five patients with myocardial iron deposition, compared with zero of eight patients without myocardial iron deposition (P=.007).

CONCLUSIONS

In this series of patients without severe hepatic iron deposition, cardiac iron overload was associated with cardiac dysfunction following liver transplantation and was related to the product of the pre-liver transplant TSAT multiplied by the number of uRBC transfused during and following the surgery.

A novel, nontoxic iron chelator, super-polyphenol, effectively induces apoptosis in human cancer cell lines

Iron chelation therapy is the main treatment for iron overload disease. Iron chelators were recently reported to be useful for cancer therapy; however, they cause side effects that make them difficult to use in some cancer patients. Thus, a novel oral iron chelator, super-polyphenol (SP), was developed for cancer therapy to decrease the side effects. SP is either water soluble or insoluble, and has different isoforms according to the number of side chains. Of these isoforms, water-soluble SP6 and SP10 appear to be the best candidates, as they have the strongest chelating abilities. In this study, we focused on the usefulness and safety of SP6 and SP10 as anti-cancer drugs, and examined their anti-cancer effects and toxicity. The results showed that SP6 and SP10 inhibited cancer cell proliferation by inducing apoptosis in HCT116, HSC-2, A549, and MCF-7 cancer cells. SP10 also inhibited tumor growth in an HCT116 xenograft model. SP6 and SP10 had no acute toxicities. An intravenous injection test revealed that SP6 and SP10 had better safety profiles than the iron chelator deferoxamine. In conclusion, SP is a novel oral iron chelator with anti-cancer effects and few adverse side effects. This is the first report of SP in the literature.

Incidentally Detected Transfusion-associated Iron Overload in 3 Children After Cancer Chemotherapy

Iron overload is a potential long-term complication among cancer survivors who received transfusions during treatment. Although there are screening guidelines for iron overload in pediatric survivors of hematopoietic stem cell transplant, these do not call for screening of other pediatric oncology patients. In our practice we incidentally discovered 3 patients in a population of 168 cancer survivors over the span of 17 years who were treated for cancer without hematopoietic stem cell transplant who had iron overload. The 3 patients had elevated liver iron on magnetic resonance imaging T2* and 2 received therapeutic phlebotomy. These cases, and others like them, suggest that collaborative groups should consider revisiting the literature to establish screening and treatment guidelines for iron overload after cancer therapy.

Clinical use of cardiac PET/MRI: current state-of-the-art and potential future applications

Combined PET/MRI is a novel imaging method integrating the advances of functional and morphological MR imaging with PET applications that include assessment of myocardial viability, perfusion, metabolism of inflammatory tissue and tumors, as well as amyloid deposition imaging. As such, PET/MRI is a promising tool to detect and characterize ischemic and non-ischemic cardiomyopathies. To date, the greatest benefit may be expected for diagnostic evaluation of systemic diseases and cardiac masses that remain unclear in cardiac MRI, as well as for clinical and scientific studies in the setting of ischemic cardiomyopathies. Diagnosis and therapeutic monitoring of cardiac sarcoidosis has the potential of a possible 'killer-application' for combined cardiac PET/MRI. In this article, we review the current evidence and discuss current and potential future applications of cardiac PET/MRI.

Pathological Roles of Iron in Cardiovascular Disease

Iron is an essential mineral required for a variety of vital biological functions. Despite being vital for life, iron also has potentially toxic aspects. Iron has been investigated as a risk factor for coronary artery disease (CAD), however, iron's toxicity in CAD patients still remains controversial. One possible mechanism behind the toxicity of iron is "ferroptosis", a newly described form of irondependent cell death. Ferroptosis is an iron-dependent form of regulated cell death that is distinct from apoptosis, necroptosis, and other types of cell death. Ferroptosis has been reported in ischemiareperfusion (I/R) injury and several other diseases. Recently, we reported that ferroptosis is a significant form of cell death in cardiomyocytes. Moreover, myocardial hemorrhage, a major event in the pathogenesis of heart failure, could trigger the release of free iron into cardiac muscle and is an independent predictor of adverse left ventricular remodeling after myocardial infarction. Iron deposition in the heart can now be detected with advanced imaging methods, such as T2 star (T2*) cardiac magnetic resonance imaging, which can non-invasively predict iron levels in the myocardium and detect myocardial hemorrhage, thus existing technology could be used to assess myocardial iron. We will discuss the role of iron in cardiovascular diseases and especially with regard to myocardial I/R injury.

Cardiotoxicity and cardiomyopathy in children and young adult survivors of hematopoietic stem cell transplant

Cardiomyopathy is common in long-term survivors of pediatric hematopoietic stem cell transplant (HSCT). Events occurring before and after HSCT when combined with specific insults during HSCT likely contribute to long-term risk. Strategies for detecting subclinical cardiomyopathy prior to patients developing overt heart failure are under investigation. Changes in HSCT preparative regimens and cardioprotective medications administered during chemotherapy may alter the risk for cardiomyopathy. Interventions in long-term survivors such as lifestyle modification and cardioactive medications are of increasing importance. Herein we review the causes of cardiac injury, discuss strategies for detection of cardiomyopathy, and evaluate therapeutic options for long-term HSCT survivors.

Efficacy and Safety of Deferasirox in Pediatric Patients of Thalassemia at a Tertiary Care Teaching Hospital

Objective:

To evaluate efficacy, safety and utilization pattern of deferasirox in paediatric patients of transfusion dependant β Thalassemia Major at a tertiary care teaching hospital in Gujarat.

Materials and Methods:

This observational, prospective-retrospective, single centre, continuous study was conducted in a tertiary care teaching hospital among paediatric patients of transfusion dependent β Thalassemia Major. Patients treated with deferasirox for not more than 12 weeks were enrolled. Details of blood transfusions, relevant investigations performed every 3 weeks and 3 months and drugs used were recorded in a pretested case record form. Parents were provided with a diary to record the details of ADRs. Data were analyzed for demographic characteristics, number and mean volume of blood transfusions, changes in serum ferritin and iron levels, number and types of ADRs and progression, causality, severity and preventability of ADRs.

Results:

Of the 60 patients enrolled, one patient was lost to follow up and four withdrew their consent. Of the remaining 55 patients, 36 were boys and 19 were girls (mean age: 6 ± 3.14 years), including patients of 1-3 years (11), 4-6 years (24), 7-10 years (12) and 11-12 years (8). Thirty six patients were born of consanguineous marriages. Adherence to blood transfusion guidelines and deferasirox prescribing and administration guidelines was observed. A serial and significant decrease in mean serum ferritin and serum iron at 3 weeks and 3 months with deferasirox treatment was observed in all age groups except that of 11-12 years. A total of 117 ADRs were observed in 52 patients from 19498 doses, most common being diarrhea (24), raised serum creatinine (15), raised hepatic enzymes (14), abdominal pain (14) and rashes (14). A reduction in dose was required in 32 cases, while a temporary stoppage was indicated in 41 cases. Deferasirox was the possible and probable cause of 65 and 51 ADRs respectively as assessed by WHO-UMC scale. Majority of ADRs were definitely preventable and mild in nature.

Conclusion:

β Thalassemia Major is more common in males. A rational prescribing of deferasirox was observed. Deferasirox effectively reduced serum ferritin and serum iron levels in these patients.

Myocardial deformation in iron overload cardiomyopathy: speckle tracking imaging in a beta-thalassemia major population

Traditional echocardiography is unable to detect neither the early stages of iron overload cardiomyopathy nor myocardial iron deposition. The aim of the study is to determine myocardial systolic strain indices in thalassemia major (TM), and assess their relationship with T2*, a cardiac magnetic resonance index of the severity of cardiac iron overload. 55 TM cases with recent cardiac magnetic resonance (CMR-T2*) underwent speckle tracking analysis to assess regional myocardial strains and rotation. The results were compared with a normal control group (n = 20), and were subsequently analyzed on the basis of the CMR-T2* values. Two TM groups were studied: TM with significant cardiac iron overload ("low" T2*, ≤20 ms; n = 21), and TM with normal T2* values ("normal" T2*, >20 ms; n = 34). TM patients show significant, uniform decrease in circumferential and radial strain (P < 0.05), and a remarkable reduction in end-systolic rotation, both global, and for all segments (P < 0.001). No significant differences were found between the low- and the normal T2* group either in regional strains and rotation or in standard echocardiographic and CMR parameters. Spearman's correlation coefficient shows no significant correlation between myocardial strains, rotation and cardiac T2* values. In conclusion, our results are in accordance with recent evidence that myocardial iron overload is not the only mechanism underlying iron cardiomyopathy in TM. Strain imaging can predict subclinical myocardial dysfunction irrespective of CMR-T2* values, although it cannot replace CMR-T2* in assessing cardiac iron overload. Finally, it might be useful to appropriately time cardioactive treatment.

Pathways to pulmonary hypertension in sickle cell disease: the search for prevention and early intervention

INTRODUCTION

Pulmonary hypertension (PH) develops in a significant number of patients with sickle cell disease (SCD), resulting in increased morbidity and mortality. This review focuses on PH pathophysiology, risk stratification, and new recommendations for screening and treatment for patients with SCD. Areas covered: An extensive PubMed literature search was performed. While the pathophysiology of PH in SCD is yet to be fully deciphered, it is known that the etiology is multifactorial; hemolysis, hypercoagulability, hypoxemia, ischemic-reperfusion injury, oxidative stress, and genetic susceptibility all contribute in varying degrees to endothelial dysfunction. Hemolysis, in particular, seems to play a key role by inciting an imbalance in the regulatory axis of nitric oxide and arginine metabolism. Systematic risk stratification starting in childhood based on clinical features and biomarkers that enable early detection is necessary. Multi-faceted, targeted interventions, before irreversible vasculopathy develops, will allow for improved patient outcomes and life expectancy. Expert commentary: Despite progress in our understanding of PH in SCD, clinically proven therapies remain elusive and additional controlled clinical trials are needed. Prevention of disease starts in childhood, a critical window for intervention. Given the complex and multifactorial nature of SCD, patients will ultimately benefit from combination therapies that simultaneously targets multiple mechanisms.

Qualitative modification and development of patient- and caregiver-reported outcome measures for iron chelation therapy

BACKGROUND

Compliance, palatability, gastrointestinal (GI) symptom, and treatment satisfaction patient- and observer-reported outcome (PRO, ObsRO) measures were developed/modified for patients with transfusion-dependent anemias or myelodysplastic syndrome (MDS) requiring iron chelation therapy (ICT).

METHODS

This qualitative cross-sectional observational study used grounded theory data collection and analysis methods and followed PRO/ObsRO development industry guidance. Patients and caregivers of patients with transfusion-dependent anemias or MDS were individually interviewed face-to-face to cognitively debrief the Compliance, Palatability, GI Symptom Diary, and Modified Satisfaction with Iron Chelation Therapy (SICT) instruments presented electronically. Interviews were conducted in sets. Interviews began open-endedly to spontaneously elicit ICT experiences. Item modifications were debriefed during the later interviews. Interviews were audio recorded, transcribed, and coded. Data was analyzed using ATLAS.ti qualitative research software.

RESULTS

Twenty-one interviews were completed (Set 1: 5 patients, 6 caregivers; Set 2: 6 patients, 4 caregivers) in 6 US cities. Mean age was 43 years for patients and 9 years for children of caregivers. Conditions requiring ICT use across groups included transfusion-dependent anemias (85.7%) and MDS (14.3%). Concepts spontaneously reported were consistent with instruments debriefed. Interview analysis resulted in PRO and ObsRO versions of each instrument: Compliance (2 items), Palatability (4 items), GI Symptom Diary (6 items), and Modified SICT (PRO = 13, ObsRO = 17 items).

CONCLUSION

Qualitative research data from cognitive interviews supports the content validity and relevance of the instruments developed/modified. Quantitative validation of these PRO and ObsRO measures is needed testing for validity, reliability, and responsiveness for future research use with new formulations of oral ICT.

Residual erythropoiesis protects against myocardial hemosiderosis in transfusion-dependent thalassemia by lowering labile plasma iron via transient generation of apotransferrin

Cardiosiderosis is a leading cause of mortality in transfusion-dependent thalassemias. Plasma non-transferrin-bound iron and its redox-active component, labile plasma iron, are key sources of iron loading in cardiosiderosis. Risk factors were identified in 73 patients with or without cardiosiderosis. Soluble transferrin receptor-1 levels were significantly lower in patients with cardiosiderosis (odds ratio 21). This risk increased when transfusion-iron loading rates exceeded the erythroid transferrin uptake rate (derived from soluble transferrin receptor-1) by >0.21 mg/kg/day (odds ratio 48). Labile plasma iron was >3-fold higher when this uptake rate threshold was exceeded, but non-transferrin-bound iron and transferrin saturation were comparable. The risk of cardiosiderosis was decreased in patients with low liver iron, ferritin and labile plasma iron, or high bilirubin, reticulocyte counts or hepcidin. We hypothesized that high erythroid transferrin uptake rate decreases cardiosiderosis through increased erythroid re-generation of apotransferrin. To test this, iron uptake and intracellular reactive oxygen species were examined in HL-1 cardiomyocytes under conditions modeling transferrin effects on non-transferrin-bound iron speciation with ferric citrate. Intracellular iron and reactive oxygen species increased with ferric citrate concentrations especially when iron-to-citrate ratios exceeded 1:100, i.e. conditions favoring kinetically labile monoferric rather than oligomer species. Excess iron-binding equivalents of apotransferrin inhibited iron uptake and decreased both intracellular reactive oxygen species and labile plasma iron under conditions favoring monoferric species. In conclusion, high transferrin iron utilization, relative to the transfusion-iron load rate, decreases the risk of cardiosiderosis. A putative mechanism is the transient re-generation of apotransferrin by an active erythron, rapidly binding labile plasma iron-detectable ferric monocitrate species.

Myelodysplastic Syndromes and Iron Chelation Therapy

Over recent decades we have been fortunate to witness the advent of new technologies and of an expanded knowledge and application of chelation therapies to the benefit of patients with iron overload. However, extrapolation of learnings from thalassemia to the myelodysplastic syndromes (MDS) has resulted in a fragmented and uncoordinated clinical evidence base. We’re therefore forced to change our understanding of MDS, looking with other eyes to observational studies that inform us about the relationship between iron and tissue damage in these subjects. The available evidence suggests that iron accumulation is prognostically significant in MDS, but levels of accumulation historically associated with organ damage (based on data generated in the thalassemias) are infrequent. Emerging experimental data have provided some insight into this paradox, as our understanding of iron-induced tissue damage has evolved from a process of progressive bulking of organs through high-volumes iron deposition, to one of ‘toxic’ damage inflicted through multiple cellular pathways. Damage from iron may, therefore, occur prior to reaching reference thresholds, and similarly, chelation may be of benefit before overt iron overload is seen. In this review, we revisit the scientific and clinical evidence for iron overload in MDS to better characterize the iron overload phenotype in these patients, which differs from the classical transfusional and non-transfusional iron overload syndrome. We hope this will provide a conceptual framework to better understand the complex associations between anemia, iron and clinical outcomes, to accelerate progress in this area.

Heart failure in haemoglobinopathies: pathophysiology, clinical phenotypes, and management

Hereditary haemoglobinopathies, mainly beta-thalassemia and sickle cell disease, constitute the most common monogenic disorders in humans, and although once geographically confined, they are currently globally distributed. They are demanding clinical entities that require multidisciplinary medical management. Despite their genotypic and phenotypic heterogeneity, the haemoglobinopathies share several similarities in pathophysiology, clinical manifestations, therapeutic requirements, and complications, among which heart failure (HF) represents a leading cause of mortality and morbidity. However, haemoglobinopathies have generally been addressed in a rather fragmentary manner. A unifying approach focusing on the underlying similarities of HF attributes in the two main entities might contribute to their better understanding, characterization, and management. In the present review, we attempt such an approach to the pathophysiology, clinical phenotypes, and management of HF in haemoglobinopathies.

Myocardial and liver iron overload, assessed using T2* magnetic resonance imaging with an excel spreadsheet for post processing in Tunisian thalassemia major patients

Thalassemia is a common genetic disorder in Tunisia. Early iron concentration assessment is a crucial and challenging issue. Most of annual deaths due to iron overload occurred in underdeveloped regions of the world. Limited access to liver and heart MRI monitoring might partially explain these poor prognostic results. Standard software programs are not available in Tunisia. This study is the first to evaluate iron overload in heart and liver using the MRI T2* with excel spreadsheet for post processing. Association of this MRI tool results to serum ferritin level, and echocardiography was also investigated. One hundred Tunisian-transfused thalassemia patients older than 10 years (16.1 ± 5.2) were enrolled in the study. The mean myocardial iron concentration (MIC) was 1.26 ± 1.65 mg/g dw (0.06-8.32). Cardiac T2* (CT2*) was under 20 ms in 30 % of patients and under 10 ms in 21 % of patients. Left ventricular ejection function was significantly lower in patients with CT2* <10 ms. Abnormal liver iron concentration (LIC >3 mg/g dw) was found in 95 % of patients. LIC was over 15 mg/g dw in 25 % of patients. MIC was more correlated than CT2* to LIC and serum ferritin. Among patients with SF <1000 μg/l, 13 % had CT2* <20 ms. Our data showed that 30 % of the Tunisian thalassemia major patients enrolled in this cohort had myocardial iron overload despite being treated by iron chelators. SF could not reliably predict iron overload in all thalassemia patients. MRI T2* using excel spreadsheet for routine follow-up of iron overload might improve the prognosis of thalassemia major patients in developing countries, such as Tunisia, where standard MRI tools are not available or expensive.

MRI Measurements of Iron Load in Transfusion-Dependent Patients: Implementation, Challenges, and Pitfalls

Magnetic resonance imaging (MRI) has played a key role in studies of iron overload in transfusion-dependent patients, providing insights into the relations among liver and cardiac iron loading, iron chelator dose, and morbidity. Currently, there is rapid uptake of these methods into routine clinical practice as part of the management strategy for iron overload in regularly transfused patients. Given the manifold methods of data acquisition and analysis, there are several potential pitfalls that may result in inappropriate decision making. Herein, we review the challenges of establishing suitable MRI techniques for tissue iron measurement in regularly transfused patients.

Is cardiac and hepatic iron status assessed by MRI T2* associated with left ventricular function in patients with idiopathic cardiomyopathy?

Excess accumulation of iron in the heart is known to aggravate cardiac function in some cases of genetic and acquired iron overload. We investigated the possible association between cardiac function and iron content in the heart and liver, estimated non-invasively by T2 star (T2*)-weighted magnetic resonance (MR) imaging among patients with cardiomyopathy. MR images were acquired on a 3.0 T MR imaging system using an 8-channel phased-array cardiac coil. Average T2* values of the heart were estimated at regions of interest that were located on short axis mid-ventricular slices positioned at the cardiac septum. In total, 82 patients were enrolled: 48 patients with dilated cardiomyopathy (DCM), 16 patients with hypertrophic cardiomyopathy (HCM), and 18 patients without apparent cardiovascular abnormalities. Cardiac T2* values were lower in the DCM group (median 18.6 ms) than in the HCM (22.0 ms) and control (21.4 ms) groups, although hepatic T2* values did not differ significantly across the groups. Among the whole population, the highest cardiac T2* tertile (≥21.2 ms) was significantly negatively associated with a low left ventricular ejection fraction (LVEF) of <50 %, and this association retained statistical significance after adjustment for sex, age, renal function, hemoglobin and hepatic T2*. Among DCM patients, both hemoglobin and cardiac T2* were selected as parameters that were, respectively, negatively and positively, associated with LVEF (P < 0.05). DCM patients with lower cardiac T2*, and thus higher iron content, were found to have lower LVEF. The possibility that cardiac iron overload may have a role in reducing the systolic cardiac function in DCM patients who do not have systemic iron overload requires further investigation in the future.

Tissue Doppler Imaging-derived Diastolic Function Assessment in Children With Sickle Cell Disease and Its Relation With Ferritin

Diastolic dysfunction has been shown to occur earlier than systolic dysfunction in iron overload states in adult patients with sickle cell disease (SCD). Tissue Doppler imaging (TDI)-derived E/E' has emerged as a noninvasive marker of diastolic function. We sought to determine diastolic function in children with SCD and study its relation with iron overload. A retrospective review of medical records of 225 pediatric patients with SCD who received an echocardiogram between January 2008 and December 2012 was performed. Echocardiographic measures including M-mode, spectral Doppler, and TDI-derived E/E' were compared with previously published data in healthy children. The left ventricular end-diastolic and end-systolic dimensions were significantly higher in SCD (P<0.0001) and the shortening fraction was similar (P=0.66). E/E' ratio was significantly higher in SCD at the mitral annulus, septum, and tricuspid annulus. In 54% of subjects, the septal E/E' was >8, indicating elevated left ventricular filling pressure. However, there was no significant correlation between ferritin level and E/E' ratios. Pediatric patients with SCD have a high prevalence of elevated estimated left ventricular filling pressure, but this does not correlate with ferritin levels.