Cardiac complications in thalassemia major

Beta-Thalassemia Major and Myocardial Iron Overload: A Longitudinal Study with Magnetic Resonance Imaging

Background

Patients with β-thalassemia major depend on lifelong transfusion, resulting in tissue iron overload. This longitudinal retrospective observational study aims to assess myocardial and liver iron overload using magnetic resonance imaging (MRI) and investigate the lag between myocardial and liver iron unloading in β-thalassemia patients undergoing chelation therapy.

Methods

Beta-thalassemia major patients with at least two MRI studies between 2016 and 2020 were enrolled. Myocardial and liver iron overload were defined as T2 ∗ less than 20 and 2.1, respectively. Outcomes included mortality, myocardial and liver T2 ∗ changes, and systolic dysfunction assessed by cardiac MRI.

Results

Fifty-five patients with a mean age of 24.62 ± 7.94 years, a mean follow-up duration of 24.3 ± 12.9 months, and a mean ferritin level of 1475.75 ± 771.12 ng/mL were enrolled. All of the abovementioned patients only took deferoxamine as the iron-chelating medication. Mortality occurred in three patients (5.5%) during follow-up. Liver T2 ∗ significantly increased (p value <0.05), while myocardial T2 ∗ showed a nonsignificant increase. Iron unloading of the myocardium was not significantly different from that of the liver and did not result in a significant lag (56% vs. 44%; p value = 0.419). Baseline myocardial T2 ∗ correlated with extramedullary hematopoiesis, weekly number of deferoxamine injections (p value <0.01), timing between the transfusions, and serum ferritin (p value <0.05).

Conclusion

Liver T2 ∗ reduced during deferoxamine chelation therapy, while myocardial T2 ∗ remained unchanged. No significant lag was observed between myocardial and liver iron unloading. Further studies are required to elucidate these findings.

The Exploring of Growth Differentiation Factor-15 and H63D Gene Polymorphisms in β-thalassemia Major: Implications for Cardiovascular Risk and Iron Overload

BACKGROUND:

β-thalassemia major (βTM) is a genetic disorder characterized by a deficiency in hemoglobin production, ineffective erythropoiesis, chronic hemolysis, lifelong blood transfusions, iron overload, and increased risk of cardiac complications.

OBJECTIVE:

The study aimed to evaluate the growth differentiation factor-15 (GDF-15) concentration in βTM patients and its correlation with cardiac complications. H63D refers to a specific mutation in the HFE gene, which is associated with hereditary hemochromatosis (HH), a genetic disorder characterized by excessive accumulation of iron in the body. This mutation involves a change of histidine (H) to aspartic acid (D) at position 63 in the HFE protein. This mutation is often only written abbreviated as (H63D).

MATERIALS AND METHODS:

This case–control study was done on 120 subjects. A total of 60 patient samples were randomly collected from the Genetic Hematology Center at the Babylon Hospital, with an age range of 10–26 years. In addition, 60 samples were collected from healthy children in the same age range as the control group; patients and controls were subdivided into (10–18) and (18–26) year groups. GDF-15 was measured by enzyme-linked immunosorbent assay, and the genotyping of mutation was done by amplification refractory mutation system-polymerase chain reaction technique.

RESULTS:

The study revealed a significant increase in ferritin (FER) and GDF-15 levels in the patients compared to controls (P< 0.001). GDF-15 showed a direct correlation with age (r= 0.244,P= 0.02) and FER (r= 0.215,P= 0.04). There was a significant difference in H63D mutations between controls and patients (P = 0.044), with a higher proportion of the C-G (heterozygous for the mutant allele) genotype observed in βTM patients (31.67%). Additionally, a notable effect of the H63D mutation on serum ferritin (higher) levels within the βTM group was observed.

CONCLUSION:

Elevations of the GDF-15 in βTM patients indicate a high risk of cardiovascular complications in patients with βTM. The H63D mutation of the hemostatic iron regulator (HFE) gene is frequently found in βTM. Although a significant effect of the mutation was obtained on serum FER levels, it did not act as a risk factor in βTM patients. However, the frequent presence of the H63D mutation in patients indicated a possible association between single-nucleotide polymorphism and the iron regulation pathway.

Echocardiographic evaluation of left atrial strain for predicting iron overload in pediatric patients with β-thalassemia with preserved ejection fraction

Pediatric patients with β-thalassemia (β-TM) with preserved ejection fraction may experience early myocardial damage. This prospective study aimed to investigate left atrial (LA) function restructure in pediatric patients with β-TM by two-dimensional speckle tracking echocardiography (2D-STE) and evaluate the value of LA strain for predicting myocardial iron overload (MIO). We recruited 50 β-TM pediatric patients and 30 healthy children aged 3-14 years. The patients were assigned to a normal left ventricular (LV) lesion group (n = 20) and an enlarged LV lesion group (n = 30). Subjects all underwent echocardiography to measure conventional cardiac function parameters and LA strain parameters. The results displayed that LA reservoir strain (LASr), conduit strain (LAScd), contractile strain (LASct) and strain rate were significantly reduced in pediatric patients with β-TM with preserved ejection fraction. LASr, LAScd, and LASct were negatively correlated with the E/e' ratio, of which LASr had the most significant correlation (r = - 0.69, P < 0.001). LASr and LASct correlated positively with T2* (r = 0.70 and 0.62, respectively, all P < 0.001). In the multiple regression, LASr and LASct were independent predictors for T2*. The areas under the curve for LASr and LASct were 0.87 (P < 0.001) and 0.78 (P = 0.004), respectively. Our results demonstrated that LA strains were dramatically impaired in pediatric patients with β-TM, and LASr is an efficient indicator for detecting LV early diastolic dysfunction in β-TM pediatric patients and reflects early myocardial damage. LASr and LASct were independently predictive of MIO, but LASr was a more sensitive predictor.

Echocardiographic Evaluation in Paediatric Sickle Cell Disease Patients: A Pilot Study

Cardiovascular involvement has a great impact on morbidity and mortality in sickle cell disease (SCD). Currently, few studies are available regarding the paediatric setting and, moreover, current guidelines for the echocardiogram screening program in the asymptomatic paediatric population are controversial. We performed a retrospective observational monocentric study on 64 SCD patients (37 male and 27 female, median age 10) at the Bambino Gesù Childrens' Hospital, who had undergone a routine transthoracic echocardiogram. In total, 46 (72%) patients had at least one cardiac abnormality. Left atrial dilatation (LAD) was present in 41 (65%) patients and left ventricular hypertrophy (LVH) was found in 29 (45%) patients. Patients with LAD showed lower median haemoglobin levels (p = 0.009), and a higher absolute reticulocyte count (p = 0.04). LVH was negatively correlated with the median haemoglobin value (p = 0.006) and positively with the reticulocyte count (p = 0.03). Moreover, we found that patients with cardiac anomalies had higher transfusion needs and a lower frequency of pain crises. In our setting, cardiac involvement has a high prevalence in the paediatric cohort and seems to be associated with specific laboratory findings, and with a specific clinical phenotype characterized by complications related to high haemodynamic load.

Genetic support of a causal relationship between iron status and atrial fibrillation: a Mendelian randomization study

Background

Atrial fibrillation is the most common arrhythmia disease. Animal and observational studies have found a link between iron status and atrial fibrillation. However, the causal relationship between iron status and AF remains unclear. The purpose of this investigation was to use Mendelian randomization (MR) analysis, which has been widely applied to estimate the causal effect, to reveal whether systemic iron status was causally related to atrial fibrillation.

Methods

Single nucleotide polymorphisms (SNPs) strongly associated (P < 5 × 10−8) with four biomarkers of systemic iron status were obtained from a genome-wide association study involving 48,972 subjects conducted by the Genetics of Iron Status consortium. Summary-level data for the genetic associations with atrial fibrillation were acquired from the AFGen (Atrial Fibrillation Genetics) consortium study (including 65,446 atrial fibrillation cases and 522,744 controls). We used a two-sample MR analysis to obtain a causal estimate and further verified credibility through sensitivity analysis.

Results

Genetically instrumented serum iron [OR 1.09; 95% confidence interval (CI) 1.02–1.16; p = 0.01], ferritin [OR 1.16; 95% CI 1.02–1.33; p = 0.02], and transferrin saturation [OR 1.05; 95% CI 1.01–1.11; p = 0.01] had positive effects on atrial fibrillation. Genetically instrumented transferrin levels [OR 0.90; 95% CI 0.86–0.97; p = 0.006] were inversely correlated with atrial fibrillation.

Conclusion

In conclusion, our results strongly elucidated a causal link between genetically determined higher iron status and increased risk of atrial fibrillation. This provided new ideas for the clinical prevention and treatment of atrial fibrillation.

Evaluation of left ventricular function and myocardial deformation in children with beta-thalassemia major by real-time three-dimensional (four-dimensional) and speckle tracking echocardiography

AIM

This study aimed to evaluate the role of real-time three-dimensional (four-dimensional) and speckle tracking echocardiography for early detection of left ventricular systolic dysfunction and also for the relationship between myocardial deformation parameters and myocardial iron load which is measured by cardiac magnetic resonance relaxation time T2* values in asymptomatic children with beta-thalassemia major.

MATERIAL AND METHODS

This multicenter cross-sectional study included 40 patients (mean age 15.4 ± 2.9, 42.1% male) and 40 healthy children whose age, gender, and body mass index-matched with patients. Each participant underwent conventional echocardiography and tissue Doppler imaging. Left ventricular ejection fraction; global longitudinal, circumferential, radial strains; twist; and torsion were measured by real-time three-dimensional and speckle tracking echocardiography. Cardiac magnetic resonance imaging T2* was measured in patients.

RESULTS

Left ventricular global longitudinal, circumferential, and radial strains were decreased despite preserved global ventricular function in patients compared to healthy children (p = p = .029, p = p < .001, p = .003, respectively). There were no statistically significant differences between patients with T2* ≥ 20 ms and patients with T2* < 20 ms for all echocardiographic parameters. Also, there were no significant correlations between all echocardiographic parameters and T2* values in all patients, those with T2* ≥ 20 ms, and T2* < 20 ms.

CONCLUSION

We found that even in asymptomatic children with beta-thalassemia major, left ventricular longitudinal, circumferential and, radial functions were impaired by real-time three-dimensional (four-dimensional) and speckle tracking echocardiography. This novel echocardiographic method might be an important tool for detecting subclinical left ventricular systolic dysfunction irrespective of T2* values.

Right ventricular function in β-thalassemia children: comparing three-dimensional echocardiography with other functional parameters

BACKGROUND

Cardiomyopathy is a major cause of mortality and morbidity in beta-thalassemia major (β-TM), and its early detection is critical for prompt management. We aimed to evaluate right ventricle (RV) function in β-TM, in absence of cardiac symptoms, using 3D echocardiography, and compare it with other functional parameters.

METHODS

Cross-sectional cohort study was conducted on 50 β-TM children with no cardiac manifestations and 50 healthy controls of matched age and sex. We evaluated RV function using; Fraction Area Change (2DE-RV FAC), Ejection Fraction (3D-RVEF), Tricuspid annular plane systolic excursion (TAPSE), Tissue Doppler imaging (TDI) systolic (S') and diastolic (E', A'), Myocardial performance index (MPI), and speckle tracking (2D-STE) of RV global longitudinal strain (LSS), systolic strain rate (SSR), early diastolic strain rate (DSR E), and late diastolic strain rate (DSR A).

RESULTS

3D-RVEF, MPI, and 2D-STE showed significant differences between the two groups. ROC curve analysis measurements had an AUC above 0.7-which indicate at least a fair discriminatory power between the β-TM group with RV dysfunction and normal controls.

CONCLUSIONS

β-TM patients have decreased RV function indices at a pre-symptomatic stage. Early detection of RV dysfunction is feasible and can allow for closer follow-up to detect pre-clinical changes.

IMPACT

The key message of this article is to emphasize the importance of the evaluation of right ventricular function in children with beta-thalassemia major. This article adds to the existing literature the use of recent echocardiographic modalities as three-dimensional echocardiography and two-dimensional speckle tracking in the evaluation of right ventricular dysfunction in beta-thalassemia children while cardiac affection is still subclinical.

IMPACT

Recent echocardiographic functional parameters can be effectively used to evaluate the right ventricle in beta-thalassemia and can detect dysfunction in asymptomatic patients allowing for early intervention.

Luspatercept: A Gigantic Step in the Treatment of Transfusion-Dependent β-Thalassemia Patients-a Quick Review

INTRODUCTION

Some studies have indicated that the use of luspatercept may be a novel and efficient treatment for β-thalassemia patients. In this article, we aimed to review the current evidence related to luspatercept prescription and its clinical effectiveness in patients with β-thalassemia.

METHODS

PubMed, Web of Science, Scopus, Trip and CENTRAL were searched up to June 2020. The inclusion criteria were English-language articles that studied the effects of luspatercept on improving anemia severity in patients with β-thalassemia in a clinical setting.

RESULTS

The search strategy yielded 273 potentially relevant articles. After searching the databases, scanning of titles, abstracts and full texts for relevancy was performed to identify suitable articles. A total of 77 articles were confirmed for full text analysis. The estimated number of patients needed to treat (NNT) for luspatercept treatment, using data derived from conducted clinical trials, according to a reduction in transfusion need of ≥ 33% or ≥ 50 from baseline, during week 13-24/week 37-48/any 12- and 24-week intervals as outcomes, was 3-5 in patients with β-thalassemia.

CONCLUSION

Based on the conducted studies, the effectiveness of luspatercept on transfusion burden and hemoglobin levels was outstanding in β-thalassemia patients. Further large and well-designed clinical studies are needed to identify any unforeseen complications subsequent to use of luspatercept, particularly when used with other treatments with potentially serious adverse effects such as anti-osteoporotic and iron chelator agents.

Evaluation of iron overload by cardiac and liver T2* in β-thalassemia: Correlation with serum ferritin, heart function and liver enzymes

Introduction: In this study, we aimed to assess the relationship of cardiac and hepatic T2* magnetic resonance imaging (MRI) values as a gold standard for detecting iron overload with serum ferritin level, heart function, and liver enzymes as alternative diagnostic methods. Methods: A total 58 patients with beta-thalassemia major who were all transfusion dependent were evaluated for the study. T2* MRI of heart and liver, echocardiography, serum ferritin level, and liver enzymes measurement were performed. The relationship between T2* MRI findings and other assessments were examined. Cardiac and hepatic T2* findings were categorized as normal, mild, moderate, and severe iron overload. Results: 22% and 11% of the patients were suffering from severe iron overload in heart and liver, respectively. The echocardiographic findings were not significantly different among different iron load categories in heart or liver. ALT level was significantly higher in patient with severe iron overload than those with normal iron load in heart (P =0.005). Also, AST level was significantly lower in normal iron load group than mild, moderate, and severe iron load groups in liver (P <0.05). The serum ferritin level was significantly inversely correlated with cardiac T2* values (r = -0.34, P =0.035) and hepatic T2* values (r = -0.52, P =0.001). Conclusion: Cardiac and hepatic T2* MRI indicated significant correlation with serum ferritin level.

Socio-religious Prognosticators of Psychosocial Burden of Beta Thalassemia Major

The study investigates the socio-religious factors in the propagation of genetically inherited disease of Beta thalassemia. The disorder which reportedly has a significant protraction through repeated cousin marriages results in the social maladjustment of the parents of the sick children due to constant depression, anxiety, and weak social interaction and may lead to social isolation as well. This research aims to find out the significant effect of socio-religious trends on psychosocial burden of beta thalassemia major among cousin and non-cousin couples in the province of Punjab in Pakistan. It takes a sample of 932 parents of sick children, among whom 735 were married with cousins and 197 with non-cousins, for data collection. The findings reveal that inadequate knowledge of the disease, insufficient or misdirected social support, stigmatization, and marriage breakups caused by the disease, superstitions, and misinterpretations of religion and the subsequent practices accordingly as significant predictors of psychosocial burden of beta thalassemia major among non-cousins and cousin couples. Additionally, it also finds patriarchy as only significant predictors of outcome variable among cousin couples.

Early detection of ventricular dysfunction by tissue Doppler echocardiography related to cardiac iron overload in patients with thalassemia

Cardiac T2* MRI is used as a gold standard for cardiac iron quantification in patients with transfusion-dependent thalassemia (TDT). We hypothesized that left ventricular (LV) diastolic dysfunction would reflect the severity of iron overload and can serve as an early detection of cardiac iron deposits. A study was conducted on all patients with TDT. Hemoglobin, serum ferritin and non-transferrin bound iron, together with a complete echocardiography and cardiac T2* MRI, were performed on all patients. Seventy-seven patients with TDT were enrolled (median age 14 years). In the patient group with a mean serum ferritin of > 2500 ng/mL during the past 12 months, there were more patients with severe cardiac iron deposits than in the group with a mean serum ferritin of ≤ 2500 ng/mL. Diastolic dysfunction was absent in all patients with a serum ferritin of < 1000 ng/mL. All patients with cardiac T2* ≤ 20 ms had grade III LV diastolic dysfunction. However, twenty-one percent of patients with cardiac T2* > 20 ms had LV diastolic dysfunction. The differences observed in pulmonary vein atrial reversal duration and mitral A-wave (PVAR-MVA) duration ≥ - 1 ms and an E/E' ratio ≥ 11 were proven to be the associated factors with the cardiac T2* ≤ 20 ms. Increased PVAR-MVA duration and increased E/E' ratio reliably reflected a severe iron overload, according to a cardiac T2* in patients with TDT. LV diastolic dysfunction can occur prior to severe cardiac iron deposition. Tissue Doppler echocardiography has the potential for the early detection of cardiac involvement in patients with TDT .

Asymptomatic intracranial aneurysms in beta-thalassemia: a three-year follow-up report

Background

No information is currently available regarding the natural history of asymptomatic intracranial aneurysms in beta-thalassemia, raising several concerns about their proper management.

Methods

We performed a prospective longitudinal three-year-long MR-angiography study on nine beta-thalassemia patients (mean-age 40.3 ± 7.5, six females, 8 transfusion dependent) harboring ten asymptomatic intracranial aneurysms. In addition, we analyzed the clinical files of all adult beta-thalassemia patients (160 patients including those followed with MR-angiography, 121 transfusion dependent) referring to our Centers between 2014 and 2019 searching for history of subarachnoid hemorrhage or history of symptomatic intracranial aneurysms.

Results

At the end of the three-year-long follow-up, no patient showed any change in the size and shape of the aneurysms, none presented new intracranial aneurysms or artery stenoses, none showed new brain vascular-like parenchymal lesions or enlargement of the preexisting ones. Besides, in our database of all adult beta-thalassemia patients, no one had history of subarachnoid hemorrhage or history of symptomatic intracranial aneurysms.

Conclusions

Incidental asymptomatic intracranial aneurysms do not seem to be associated, in beta-thalassemia, with an increased risk of complications (enlargement or rupture) at least in the short term period, helping to optimize human and economic resources and patient compliance during their complex long-lasting management.

Arrhythmias and Sudden Cardiac Death in Beta-Thalassemia Major Patients: Noninvasive Diagnostic Tools and Early Markers

Beta-thalassemias are a group of inherited, autosomal recessive diseases, characterized by reduced or absent synthesis of beta-globin chains of the hemoglobin tetramer, resulting in variable phenotypes, ranging from clinically asymptomatic individuals to severe anemia. Three main forms have been described: heterozygotes, homozygotes β+, and homozygotes β°. Beta-thalassemia major (β-TM), the most serious form, is characterized by an absent synthesis of globin chains that are essential for hemoglobin formation, causing chronic hemolytic anemia. Cardiac complications represent a leading cause of mortality in β-TM patients, although an important and progressive increase of life expectancy has been demonstrated after the introduction of chelating therapies. Iron overload is the primary factor of cardiac damage resulting in thalassemic cardiomyopathy, in which diastolic dysfunction usually happens before systolic impairment and overt heart failure (HF). Although iron-induced cardiomyopathy is slowly progressive and it usually takes several decades for clinical and laboratory features of cardiac dysfunction to manifest, arrhythmias or sudden death may be present without signs of cardiac disease and only if myocardial siderosis is present. Careful analysis of electrocardiograms and other diagnostic tools may help in early identification of high-risk β-TM patients for arrhythmias and sudden cardiac death.

MRI evaluation of hepatic and cardiac iron burden in pediatric thalassemia major patients: spectrum of findings by T2*

Background

Iron deposition distorts the local magnetic field exerting T2* signal decay. Biopsy, serum ferritin, echocardiography are not reliable to adjust iron chelation therapy. Quantified MRI signal decay can replace biopsy to diagnose iron burden, guide treatment, and follow up. The objective of this study is to evaluate the role of T2* in quantification of the liver and heart iron burden in thalassemia major patients. This cross-sectional study included 44 thalassemia patients who were referred to MRI unit, underwent T2* MRI.

Results

Twenty-one male (47.7%) and 23 female (52.3%) were included (age range 6–15 years, mean age 10.9 ± 2.9 years). Patients with excess hepatic iron show the following: 11/40 (27.5%) mild, (13/40) 32.5% moderate, and (14/40) 35% severe liver iron overload. High statistical significance regarding association between LIC and liver T2* (p = 0.000) encountered. Cardiac T2* values showed no relationship with age (p = 0.6).

Conclusion

T2* is a good method to quantify, monitor hepatic and myocardial iron burden, guiding chelation therapy and prevent iron-induced cardiac complications.

Left Ventricular Regional Function in Children with Beta Thalassemia with No Cardiac Manifestations (Four-Dimensional Echocardiographic Study)

Early detection of myocardial dysfunction is essential for the management of patients with thalassemia. Four-dimensional echocardiography imaging technique may be useful for detecting subclinical cardiovascular disease. To evaluate the 4-dimensional echocardiographic strain in children with beta thalassemia major with no cardiac manifestation and correlate it with other echocardiographic parameters. This is a prospective cross-sectional cohort Study included 200 children, 1-18 years-old. They were divided into: One hundred children with p-Thalassemia major with no clinical cardiac manifestations and 100 healthy children as a control group. They were subjected to the following investigations: Complete blood count, serum ferritin and Four-dimensional echocardiographic strains (Longitudinal, Circumferential, Radial and Area strains). There was no significant difference between the two groups as regard mitral annulus systolic velocity (S wave), E/A ratio and iso-volumic acceleration, but there was a significant difference as regard to ejection fraction, left ventricle mass, sphericity index and myocardial performance index. The mean values of Left Ventricular Strains (Longitudinal, Circumferential, Radial and Area strains) were significantly lower in patients with thalassemia (- 14.86 ± 12.13, - 8.01 ± 3.829, 33.13 ± 10.61, - 19.45 ± 6.866) than controls (- 19.13 ± 1.502, - 16.32 ± 1.34, 37.28 ± 4.209, - 22.94 ± 3.06) than controls respectively with a positive correlation with 2-Dimensional strain. Strain parameters of the left ventricle obtained by four-dimensional.

No increased cerebrovascular involvement in adult beta-thalassemia by advanced MRI analyses

Beta-thalassemia-related anemia and chronic hypercoagulative state are supposed to cause cumulative cerebrovascular damage with consequent parenchymal/vascular changes and functional impairment. However, recent conventional MRI/MR-angiography investigations failed to show an increased cerebrovascular involvement in beta-thalassemia patients managed according to current treatment guidelines, in spite of significantly decreased full-scale IQ scores. We therefore investigated those patients and controls by means of advanced quantitative MRI analyses (based on magnetization transfer and diffusion tensor imaging) searching for signs of possible cerebrovascular injuries undetected by conventional MRI/MR-angiography. The 3 T-MRI study protocol included diffusion tensor imaging and 3D-multi-echo FLASH sequences for magnetization transfer analysis. Whole-brain voxel-based analyses showed that magnetization transfer, fractional anisotropy, and mean, radial and axial diffusivity do not differ between healthy controls and beta-thalassemia patients (considered as a whole group or as distinct transfusion dependent and non-transfusion dependent subgroups). No correlation emerged between all the considered MRI metrics and cognitive findings (full-scale IQ) or the main clinical and laboratory data. According to our findings, adult neurologically-asymptomatic beta-thalassemia patients (regardless of clinical severity) do not seem to present an increased disease-related cerebrovascular vulnerability compared to healthy controls downsizing the need of regular brain MRI monitoring, at least when the current treatment guidelines are followed.

No evidence of increased cerebrovascular involvement in adult neurologically-asymptomatic β-Thalassaemia. A multicentre multimodal magnetic resonance study

Multi-factorial causes jeopardize brain integrity in β-thalassaemia. Intracranial parenchymal and vascular changes have been reported among young β-thalassaemia patients but conventional magnetic resonance imaging (MRI) findings are contradictory making early MRI and magnetic resonance angiography (MRA)/venography monitoring a matter of debate. This study prospectively investigated 75 neurologically asymptomatic β-thalassaemia patients (mean-age 35·2 ± 10·7 years; 52/75 transfusion-dependent; 41/75 splenectomised) using a 3T magnetic resonance scanner; clinical, laboratory and treatment data were also collected. White matter ischaemic-like abnormalities, intracranial artery stenoses, aneurysms and sinus venous thrombosis were compared between patients and 56 healthy controls (mean-age 33·9 ± 10·8 years). No patient or control showed silent territorial or lacunar strokes, intracranial artery stenoses or signs of sinus thrombosis. White matter lesions were found both in patients (35/75, 46·7%) and controls (28/56, 50·0%), without differences in terms of number (4·0 ± 10·6 vs. 4·6 ± 9·1, P = 0·63), size and Fazekas' Score. Intracranial aneurysms did not differ between patients and controls for incidence rate (7/75, 9·3% vs. 5/56, 8·9%), size and site. Vascular and parenchymal abnormality rate did not differ according to treatments or clinical phenotype. According to this study, asymptomatic β-thalassaemia patients treated according to current guidelines do not seem to carry an increased risk of brain and intracranial vascular changes, thus weakening recommendations for regular brain MRI monitoring.

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.

Life-Threatening Drug-Induced Liver Injury in a Patient with β-Thalassemia Major and Severe Iron Overload on Polypharmacy

A 20-year-old male affected by transfusion-dependent β-thalassemia (β-thal), was prescribed intensive chelation therapy with deferoxamine (DFO) and deferiprone (DFP) because of severe hepatic and cardiac iron overload and β-blocker and warfarin to manage a previous event of atrial fibrillation (AFib) and heart failure. After a few months, he developed critical liver failure, renal tubulopathy and severe electrolyte imbalance. Laboratory and instrumental evaluations were performed to carry out differential diagnosis of acute liver failure and an exclusion diagnosis of drug induced liver injury (DILI) was made. The cholestatic pattern suggested warfarin as the main causative agent and polypharmacy, liver iron overload and heart failure as aggravating factors. Warfarin is a drug commonly prescribed in thalassemia patients who often need polypharmacy for the management of anemia- and iron-related complications. Strict monitoring and multidisciplinary approaches are mandatory to avoid preventable mortality in this fragile population.

Thalassemia in the laboratory: pearls, pitfalls, and promises

Thalassemia is one of the most common hereditary disorders of the developing world, and it is associated with severe anemia and transfusion dependence. The global health burden of thalassemia has increased as a result of human mobility and migration in recent years. Depending on inherited mutations, thalassemia patients exhibit distorted hemoglobin (Hb) patterns and deviated red cell indices, both of which can be used to support identification by diagnostic tools. Diagnostic approaches vary depending on the target population and the aim of the testing. Current methods, which are based on Hb patterns, are used for first-line screening, whereas molecular testing is needed for conformation of the results and for prenatal and preimplantation genetic diagnosis. In the present paper, we review the diagnostic parameters, pitfalls, interfering factors, and methods; currently available best-practice guidelines; quality assurance and standardization of the procedures; and promising laboratory technologies for the future of thalassemia diagnosis.

Iron Overload and Chelation Therapy in Hemoglobinopathies

Iron overload (IOL) is highly prevalent among patients with hemoglobinopathies; both transfusion dependent thalassemia (TDT) and non-transfusion dependent thalassemia (NTDT). Whether IOL is secondary to regular transfusions like in TDT, or develops from increased intestinal absorption like in NTDT, it can cause significant morbidity and mortality. In TDT patients, iron accumulation in organ tissues is highly evident, and leads to organ toxicity and dysfunction. IOL in NTDT patients is cumulative with advancing age, and concern with secondary morbidity starts beyond the age of 10 years, as shown by the OPTIMAL CARE study. Several modalities are available for the diagnosis and monitoring of IOL. Serum ferritin (SF) assessment is widely available and heavily relied on in resource-poor countries. Non-invasive iron monitoring using MRI has become the gold standard to diagnose IOL. Three iron chelators are currently available for the treatment of IOL: deferoxamine (DFO) in subcutaneous or intravenous injection, oral deferiprone (DFP) in tablet or solution form, and oral deferasirox (DFX) in dispersible tablet (DT) and film-coated tablet (FCT). Today, the goal of ICT is to maintain safe levels of body iron at all times. Appropriate tailoring ICT with chelator choices and dose adjustment must be implemented in a timely manner. Clinical decision to initiate, adjust and stop ICT is based on SF, MRI-LIC and cardiac T2*. In this article, we review the mechanism of IOL in both TDT and NTDT, the pathophysiology behind it, its complications, and the different ways to assess and quantify it. We will also discuss the different ICT modalities available, and the emergence of novel therapies.

Magnetic resonance imaging during management of patients with transfusion-dependent thalassemia: a single-center experience

BACKGROUND

Cardiac and hepatic magnetic resonance imaging evaluation during treatment can tailor physicians' chelation therapy titrations.

AIM

The aim of the study was to assess the relationship of cardiac and hepatic T2* values with chelation therapy in patients with transfusion-dependent thalassemia (TDT).

METHODS

A total of 106 patients with TDT who were followed up in Istanbul Medical Faculty Thalassemia Center were evaluated for the study. Forty-eight (45%) patients with TDT had more than one consecutive MRI examination. The patients were divided into three subgroups according to the cardiac T2* values as the high-risk group (T2* MRI < 10 ms), medium-risk group (T2* MRI 10-20 ms), and the low-risk group (T2* MRI > 20 ms).

RESULTS

The majority of patients used DFX (deferasirox) (79%) and deferiprone (DFP) (17%). Approximately 80% of patients according to cardiac T2* value and 40% of patients according to hepatic T2* value were initially in the low-risk group. Patients with follow-up MRI examinations exhibited significant improvement in liver iron concentration, which correlated with an increase in hepatic T2* values. The decrease of liver iron concentration was prominent in the DFX group (p < 0.01). The serum ferritin level was significantly correlated with liver iron concentrations (rs = 0.65, p < 0.001), hepatic T2* value (rs = - 0.62, p < 0.001), but not with cardiac T2* value (rs = - 0.20, p = 0.07).

CONCLUSION

Cardiovascular and hepatic MRI is a useful follow-up tool during the assessment of risk groups and chelation therapy of patients with TDT. Consecutive MRI tests showed good monitoring of cardiac and liver iron overload.