National networking in rare diseases and reduction of cardiac burden in thalassemia major

Early Detection of Myocardial Involvement in Thalassemia Intermedia Patients: Multiparametric Mapping by Magnetic Resonance Imaging

BACKGROUND

No study has assessed myocardial T1 and T2 values in patients with beta-thalassemia intermedia (β-TI).

PURPOSE

To assess the prevalence of myocardial involvement in β-TI patients by T2* relaxometry and native T1 and T2 mapping and to determine the correlation of myocardial relaxation times with demographic and clinical parameters.

STUDY TYPE

Prospective matched-cohort study.

SUBJECTS

42 β-TI patients (27 females, 39.65 ± 12.32 years), enrolled in the Extension-Myocardial Iron Overload in Thalassaemia Network, and 42 age- and sex-matched healthy volunteers (27 females, 40.01 ± 11.36 years) and thalassemia major (TM) patients (27 females, 39.27 ± 11.57 years).

FIELD STRENGTH/SEQUENCE

1.5 T/multi-echo gradient echo, modified Look-Locker inversion recovery, multi-echo fast-spin-echo, cine balanced steady-state-free precession, and late gadolinium enhancement (LGE) sequences.

ASSESSMENT

Hepatic, pancreatic, and left ventricular (LV) T2* values, LV native T1 and T2 values, biventricular ejection fractions and volumes, and presence and extent of replacement myocardial fibrosis.

STATISTICAL TESTS

Comparisons between two groups were performed with two-sample t tests, Wilcoxon's signed rank tests, or χ2 testing. Correlation analysis was performed using Pearson's or Spearman's test. P < 0.05 was considered statistically significant.

RESULTS

β-TI patients had significantly higher LV T2 values than healthy subjects (56.84 ± 4.03 vs. 52.46 ± 2.50 msec, P < 0.0001) and significantly higher LV T1 values than TM patients (1018.32 ± 48.94 vs. 966.66 ± 66.47 msec, P < 0.0001). In β-TI, female gender was associated with significantly increased LV T1 (P = 0.041) and T2 values (P < 0.0001), while splenectomy and presence of regular transfusions were associated with significantly lower LV T1 values (P = 0.014 and P = 0.001, respectively). In β-TI patients, all LV relaxation times were significantly correlated with each other (T2*-T1: P = 0.003; T2*-T2: P = 0.003; T1-T2: P < 0.0001). Two patients with a reduced LV T2* also had a reduced LV T1, while only one had a reduced LV T2. Three patients had a reduced LV T1 but a normal LV T2*; 66.7% of the patients had an increased LV T2. All LV relaxation times were significantly correlated with pancreas T2* values (T2*: P = 0.033; T1: P < 0.0001; T2: P = 0.014). No LV relaxation time was associated (P > 0.05) with hepatic iron concentration, biventricular function parameters, or LGE presence.

CONCLUSION

The combined use of all three myocardial relaxation times has potential to improve sensitivity in the detection of early/subclinical myocardial involvement in β-Tl patients.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY: Stage 2.

What is the importance of monitoring iron levels in different organs over time with magnetic resonance imaging in transfusion-dependent thalassemia patients?

INTRODUCTION

Iron overload is the main pathophysiological driver of organ damage in transfusion-dependent thalassemia (TDT). Magnetic resonance imaging (MRI) provides detailed insights into the distribution and severity of iron accumulation in the different organs.

AREAS COVERED

This special report describes the impact of MRI on clinical and therapeutic management and short- and long-term outcomes in TDT patients. PubMed, Scopus, and Google Scholar databases were searched to identify the relevant studies published before November 2024.

EXPERT OPINION

Cardiac and hepatic MRI are now well-established modalities, integrated into the clinical practice. They have become essential for tailoring iron chelation therapies to the specific patient's needs and for monitoring treatment efficacy. The improved control of cardiac iron burden has translated into reduced morbidity and mortality. The MRI accessibility remains limited in resource-limited settings and progress in this field relies on educating and training centers to ensure accurate execution and interpretation. The clinicopathological significance, prognostic value, and reproducibility of pancreatic iron levels assessment have been established, charting a path toward its clinical use. There are limited data about renal, adrenal, and pituitary iron deposition, and more research is needed to fully establish the functional significance and to standardize and validate the MRI protocols.

Prevalence and Correlates of Dilated and Non-Dilated Left Ventricular Cardiomyopathy in Transfusion-Dependent Thalassemia: Data from a National, Multicenter, Observational Registry

We investigated the prevalence, clinical characteristics, and prognostic role of dilated cardiomyopathy (DCM) and non-dilated left ventricular cardiomyopathy (NDLVC) in patients with transfusion-dependent β-thalassemia (β-TDT). We retrospectively included 415 β-TDT patients who underwent cardiovascular magnetic resonance to quantify myocardial iron overload (MIO) and biventricular function parameters and to detect replacement myocardial fibrosis. Demographic and laboratory parameters were comparable among patients with no overt cardiomyopathy (NOCM; n = 294), DCM (n = 12), and NDLVC (n = 109), while cardiac size and systolic function were significantly different. Compared to NOCM patients, DCM and NDLVC patients had a higher prevalence of MIO and replacement myocardial fibrosis. During a mean follow-up of 57.03 ± 18.01 months, cardiac complications occurred in 32 (7.7%) patients: 15 heart failures, 15 supraventricular arrhythmias, and 2 pulmonary hypertensions. Compared to the NOCM group, both the NDLVC and the DCM groups were associated with a significantly increased risk of cardiac complications (hazard ratio = 4.26 and 8.81, respectively). In the multivariate analysis, the independent predictive factors were age, MIO, and the presence of DCM and NDLVC versus the NOCM phenotype. In β-TDT, the detection of NDLVC and DCM phenotypes may hold value in predicting cardiac outcomes.

Convolutional neural networks for automatic MR classification of myocardial iron overload in thalassemia major patients

OBJECTIVES

To develop a deep-learning model for supervised classification of myocardial iron overload (MIO) from magnitude T2* multi-echo MR images.

MATERIALS AND METHODS

Eight hundred twenty-three cardiac magnitude T2* multi-slice, multi-echo MR images from 496 thalassemia major patients (285 females, 57%), labeled for MIO level (normal: T2* > 20 ms, moderate: 10 ≤ T2* ≤ 20 ms, severe: T2* < 10 ms), were retrospectively studied. Two 2D convolutional neural networks (CNN) developed for multi-slice (MS-HippoNet) and single-slice (SS-HippoNet) analysis were trained using 5-fold cross-validation. Performance was assessed using micro-average, multi-class accuracy, and single-class accuracy, sensitivity, and specificity. CNN performance was compared with inter-observer agreement between radiologists on 20% of the patients. The agreement between patients' classifications was assessed by the inter-agreement Kappa test.

RESULTS

Among the 165 images in the test set, a multi-class accuracy of 0.885 and 0.836 was obtained for MS- and SS-Hippo-Net, respectively. Network performances were confirmed on external test set analysis (0.827 and 0.793 multi-class accuracy, 29 patients from the CHMMOTv1 database). The agreement between automatic and ground truth classification was good (MS: κ = 0.771; SS: κ = 0.614), comparable with the inter-observer agreement (MS: κ = 0.872, SS: κ = 0.907) evaluated on the test set.

CONCLUSION

The developed networks performed classification of MIO level from multiecho, bright-blood, and T2* images with good performances.

KEY POINTS

Question MRI T2* represents the established clinical tool for MIO assessment. Quality control of the image analysis is a problem in small centers. Findings Deep learning models can perform MIO staging with good accuracy, comparable to inter-observer variability of the standard procedure. Clinical relevance CNN can perform automated staging of cardiac iron overload from multiecho MR sequences facilitating non-invasive evaluation of patients with various hematologic disorders.

Left ventricular diastolic and systolic functions by cardiac magnetic resonance in beta-thalassemia major: correlation with clinical findings and cardiac complications

This cross-sectional study explored the association of left ventricular (LV) fractional area change (FAC) with demographic characteristics, clinical data, cardiovascular magnetic resonance (CMR) findings, and cardiac complications (heart failure and arrythmias) in patients with beta-thalassemia major (β-TM). We included 292 β-TM patients (151 females, 36.72 ± 11.76 years) consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia project and 20 healthy controls (8 females, 36.97 ± 3.54 years). CMR was used to assess FAC and derive LV systolic and diastolic indexes, to quantify myocardial iron overload (MIO) by the T2* technique and LV volumes and ejection fraction, and to detect late gadolinium enhancement (LGE). Healthy subjects and β-TM patients showed comparable LV systolic and diastolic indexes. In β-TM, the LV systolic index was significantly correlated with global heart T2* values, and patients with significant MIO (T2*<20ms) were more likely to have a reduced LV systolic index compared to those without MIO (odds ratio-OR = 3.13; p = 0.013). In multivariate analysis, global heart T2* values and positive LGE emerged as independent determinants of the LV systolic index. The number of segments with LGE inversely correlated with the LV systolic index (p = 0.003). Patients with a reduced LV systolic index were more likely to have cardiac diseases than those with a normal LV systolic index (OR = 5.34; p < 0.0001). No significant correlates were found for the LV diastolic index. In well-treated β-TM patients, MIO and LGE were the strongest determinants of the LV systolic index, and a reduced LV systolic index was associated with an increased risk of cardiac complications.

Biatrial and Biventricular Reference Ranges Based on Cardiac Magnetic Resonance in Sickle Cell Disease Patients Without Heart Damage

BACKGROUND/OBJECTIVES

We aimed to establish biatrial and biventricular reference ranges using cardiac magnetic resonance (CMR) parameters in SCD patients without heart damage.

METHODS

This study compared CMR parameters, quantified by cine SSFP sequences, in 48 adult SCD patients without apparent cardiac involvement (defined by the absence of known risk factors, normal electrocardiogram, and no macroscopic myocardial fibrosis or significant cardiac iron on T2* CMR) to matched cohorts of 96 healthy controls and 96 thalassemia major (TM) patients without cardiac damage. Nine paediatric SCD patients were also analysed and compared to age- and gender-matched groups of nine TM patients and nine healthy subjects.

RESULTS

In all groups, studied males displayed higher biventricular volumes and mass indexes than females. Male SCD patients showed significantly higher left ventricular (LV) end-diastolic volume index (EDVI), LV end-systolic volume index (ESVI), LV stroke volume index (SVI), cardiac index, LV and right ventricular (RV) mass index, and atrial areas than healthy subjects. Females with SCD exhibited increased LV EDVI, LV SVI, RV mass index, and left atrial area index compared to healthy controls. SCD and TM patients showed comparable biatrial areas and biventricular volumes and function. When compared to TM, SCD males exhibited a larger mass index, while SCD females showed an increased RV mass index. CMR parameters were similar across all paediatric groups.

CONCLUSIONS

By establishing the biatrial and biventricular reference ranges through CMR for adult male and female SCD patients, we aimed to prevent possible misdiagnosis of cardiomyopathy in this population by taking into account cardiac adaptation due to anaemia.

Cardiovascular magnetic resonance in β-thalassemia major: beyond T2

Β-thalassemia major (TM) patients underwent regular transfusions to prevent complications of chronic anemia. However, these regular transfusions result in progressive iron accumulation in vital organs, including the heart. Myocardial iron overload can lead to cardiac dysfunction and ultimately to heart failure. Diagnosis of cardiac dysfunction in β-TM patients is usually made through clinical examination, electrocardiogram, and echocardiography. Cardiac magnetic resonance (CMR), through the measurement of T2* relaxation time, represents the diagnostic modality of choice for assessing myocardial iron overload and guiding the iron chelation therapy. Despite a tailored chelation therapy reducing myocardial iron overload, heart failure remains the leading cause of morbidity and mortality even in well-treated β-TM patients. Advances in CMR, including myocardial strain, parametric mapping (T1, T2, and extracellular volume), and late gadolinium enhancement (LGE) measurements, have expanded its role in the diagnosis, prognosis, and follow-up of these patients. This review seeks to offer a thorough overview of the potential uses of CMR in β-TM, extending beyond the established role of T2* measurement in guiding chelation therapy. It delves into the emerging applications of new CMR imaging biomarkers that could improve the overall management of β-TM patients.

Global longitudinal strain by cardiac magnetic resonance is associated with cardiac iron and complications in beta-thalassemia major patients

BACKGROUND

The aim of this cross-sectional study was to investigate the association of left ventricular (LV) strain parameters with demographics, clinical data, cardiovascular magnetic resonance (CMR) findings, and cardiac complications (heart failure and arrhythmias) in patients with β-thalassemia major (β-TM).

METHOD

We considered 266 β-TM patients (134 females, 37.08 ± 11.60 years) consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia (E-MIOT) project and 80 healthy controls (50 females, mean age 39.77 ± 11.29 years). The CMR protocol included cine images for the assessment of global longitudinal strain (GLS), global circumferential strain (GCS), and global radial strain (GRS) using feature tracking (FT) and for the quantification of LV function parameters, the T2* technique for the assessment of myocardial iron overload, and late gadolinium enhancement (LGE) technique.

RESULTS

In comparison to the healthy control group, β-TM patients showed impaired GLS, GCS, and GRS values. Among β-TM patients, sex was identified as the sole independent determinant of all LV strain parameters. All LV strain parameters displayed a significant correlation with LV end-diastolic volume index, end-systolic volume index, mass index, and ejection fraction, and with the number of segments exhibiting LGE. Only GLS exhibited a significant correlation with global heart T2* values and the number of segments with T2* < 20 ms. Patients with cardiac complications exhibited significantly impaired GLS compared to those without cardiac complications.

CONCLUSION

In patients with β-TM, GLS, GCS, and GRS were impaired in comparison with control subjects. Among LV strain parameters, only GLS demonstrated a significant association with cardiac iron levels and complications.

Left atrial strain in patients with β-thalassemia major: a cross-sectional CMR study

OBJECTIVES

The aim of this cross-sectional study was to investigate the association of left atrial (LA) strain parameters with demographics, clinical data, cardiovascular magnetic resonance (CMR) findings, and cardiac complications (heart failure and arrhythmias) in a cohort of patients with β-thalassemia major (β-TM).

MATERIALS AND METHODS

We considered 264 β-TM patients (133 females, 36.79 ± 11.95 years) consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia (E-MIOT) project. Moreover, we included 35 sex- and age-matched healthy controls (14 females, mean age 37.36 ± 17.52 years). Reservoir, conduit, and booster LA functions were analysed by CMR feature tracking using dedicated software.

RESULTS

Compared to the healthy control group, β-TM patients demonstrated lower LA reservoir strain and booster strains, as well as LA reservoir and booster strain rates. However, no differences were found in LA conduit deformation parameters. In β-TM patients, ageing, sex, and left ventricle (LV) volume indexes were independent determinants of LA strain parameters. The number of segments with late gadolinium enhancement (LGE) significantly correlated with all LA strain parameters, with the exception of the LA conduit rate. Patients with cardiac complications exhibited significantly impaired strain parameters compared to patients without cardiac complications.

CONCLUSION

In patients with β-TM, LA strain parameters were impaired compared to control subjects, and they exhibited a significant correlation with the number of LV segments with LGE. Furthermore, patients with cardiac complications had impaired left atrial strain parameters. Clinical relevance statement In patients with β-thalassemia major, left atrial strain parameters were impaired compared to control subjects and emerged as a sensitive marker of cardiac complications, stronger than cardiac iron levels.

KEY POINTS

• Compared to healthy subjects, β-thalassemia major patients demonstrated significantly lower left atrial reservoir strain and booster strains, as well as left atrial reservoir and booster strain rates. • In β-thalassemia major, ageing, sex, and left ventricular volume indexes were independent determinants of left atrial strain parameters, while left atrial strain parameters were not correlated with myocardial iron overload. • An independent association between reduced left atrial strain parameters and a history of cardiac complications was found in β-thalassemia major patients.

Left and right atrioventricular coupling index in patients with beta-thalassemia major

The aim of this cross-sectional study was to investigate the relationship of left atrioventricular coupling index (LACI) and right atrioventricular coupling index (RACI) with demographics, clinical data, cardiovascular magnetic resonance findings, and cardiac complications (heart failure, arrhythmias, and pulmonary hypertension) in a cohort of patients with beta-thalassemia major (β-TM). We evaluated 292 β-TM patients (151 females, 36.72 ± 11.76 years) consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia (E-MIOT) project. Moreover, we assessed 32 sex- and age-matched healthy controls (12 females, mean age 40.78 ± 14.35 years). LACI was determined by calculating the ratio of the left atrium end-diastolic volume to the left ventricle end-diastolic volume, while RACI was defined by calculating the ratio of the right atrium end-diastolic volume to the right ventricle end-diastolic volume. Compared to healthy control, β-TM demonstrated increased LACI (22.99 ± 13.58% vs. 16.05 ± 5.28%; p < 0.0001) and RACI (27.84 ± 10.30% vs. 17.06 ± 5.03%; p < 0.0001). Aging, diabetes, splenectomy, and the presence of late gadolinium enhancement (LGE) showed a significant positive association with both LACI and RACI. In stepwise regression analysis, the presence of LGE was found to be an independent predictor of both impaired LACI and RACI (β coefficient = 0.244, p < 0.0001 and β coefficient = 0.218, p = 0.003; respectively). LACI and RACI were not correlated with myocardial iron overload. Patients with cardiac complications had significantly higher LACI and RACI than patients without cardiac complications. In patients with β-TM, LACI and RACI were significantly associated with the presence of LV LGE. In addition, patients with cardiac complications had impaired LACI and RACI.

Multiparametric cardiac magnetic resonance in patients with thalassemia intermedia: new insights from the E-MIOT network

PURPOSE

In a relatively large cohort of thalassemia intermedia (TI) patients, we systematically investigated myocardial iron overload (MIO), function, and replacement fibrosis using cardiac magnetic resonance (CMR), we assessed the clinical determinants of global heart T2* values, and we explored the association between multiparametric CMR findings and cardiac complications.

MATERIALS AND METHODS

We considered 254 beta-TI patients (43.14 ± 13.69 years, 138 females) consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia project. MIO was quantified by T2* technique and biventricular function and atrial areas by cine images. Macroscopic myocardial fibrosis was detected by late gadolinium enhancement technique.

RESULTS

Compared to never/sporadically transfused patients, regularly transfused (RT)-TI patients exhibited significantly lower global heart T2* values, biventricular end-diastolic volume indexes, left ventricular mass index, and cardiac index. In RT-TI patients, age and serum ferritin levels were the strongest predictors of global heart T2* values. Independently from the transfusional state, cardiac T2* values were not associated with biventricular function. Of the 103 (40.6%) patients in whom the contrast medium was administrated, 27 (26.2%) had replacement myocardial fibrosis. Age, sex distribution, cardiac iron, and biventricular function parameters were comparable between patients without and without replacement myocardial fibrosis. Twenty-five (9.8%) patients had a history of cardiac complications (heart failure and arrhythmias). Increased age and replacement myocardial fibrosis emerged as significant risk markers for cardiac complications.

CONCLUSIONS

In TI, regular transfusions are associated with less pronounced cardiac remodeling but increase the risk of MIO. Replacement myocardial fibrosis is a frequent finding associated with cardiac complications.

Impact of genotype on multi-organ iron and complications in patients with non-transfusion-dependent β-thalassemia intermedia

We evaluated the impact of the genotype on clinical and hematochemical features, hepatic and cardiac iron levels, and endocrine, hepatic, and cardiovascular complications in non-transfusion-dependent (NTD) β-thalassemia intermedia (TI) patients. Sixty patients (39.09 ± 11.11 years, 29 females) consecutively enrolled in the Myocardial Iron Overload in Thalassemia project underwent Magnetic Resonance Imaging to quantify iron overload, biventricular function parameters, and atrial areas and to detect replacement myocardial fibrosis. Three groups of patients were identified: homozygous β+ (N = 18), heterozygous β0β+ (N = 22), and homozygous β0 (N = 20). The groups were homogeneous for sex, age, splenectomy, hematochemical parameters, chelation therapy, and iron levels. The homozygous β° genotype was associated with significantly higher biventricular end-diastolic and end-systolic volume indexes and bi-atrial area indexes. No difference was detected in biventricular ejection fractions or myocardial fibrosis. Extramedullary hematopoiesis and leg ulcers were significantly more frequent in the homozygous β° group compared to the homozygous β+ group. No association was detected between genotype and liver cirrhosis, hypogonadism, hypothyroidism, osteoporosis, heart failure, arrhythmias, and pulmonary hypertension. Heart remodelling related to a high cardiac output state cardiomyopathy, extramedullary hematopoiesis, and leg ulcers were more pronounced in patients with the homozygous β° genotype compared to the other genotypes analyzed. The knowledge of the genotype can assist in the clinical management of NTD β-TI patients.

Liver steatosis in patients with transfusion-dependent thalassaemia

We evaluated the prevalence and the clinical associations of liver steatosis (LS) in patients with transfusion-dependent thalassaemia (TDT). We considered 301 TDT patients (177 females, median age = 40.61 years) enrolled in the Extension-Myocardial Iron Overload in Thalassaemia Network, and 25 healthy subjects. Magnetic resonance imaging was used to quantify iron overload and hepatic fat fraction (FF) by T2* technique and cardiac function by cine images. The glucose metabolism was assessed by the oral glucose tolerance test (OGTT). Hepatic FF was significantly higher in TDT patients than in healthy subjects (median value: 1.48% vs. 0.55%; p = 0.013). In TDT, hepatic FF was not associated with age, gender, serum ferritin levels or liver function parameters, but showed a weak inverse correlation with high-density lipoprotein cholesterol. The 36.4% of TDT patients showed LS (FF >3.7%). Active hepatitis C virus (HCV) infection, increased body mass index and hepatic iron were independent determinants of LS. A hepatic FF >3.53% predicted the presence of an abnormal OGTT. Hepatic FF was not correlated with cardiac iron, biventricular volumes or ejection fractions, but was correlated with left ventricular mass index. In TDT, LS is a frequent finding, associated with iron overload, increased weight and HCV, and conveying an increased risk for the alterations of glucose metabolism.

Multiparametric Cardiac Magnetic Resonance Assessment in Sickle Beta Thalassemia

Cardiac involvement in sickle beta thalassemia (Sβ-thal) patients has been poorly investigated. We aimed to evaluate cardiac function and myocardial iron overload by cardiovascular magnetic resonance (CMR) in patients with Sβ-thal. One-hundred and eleven Sβ-thal patients consecutively enrolled in the Myocardial Iron Overload in Thalassemia (MIOT) network were studied and compared with 46 sickle cell anemia (SCA) patients and with 111 gender- and age- matched healthy volunteers. Cine images were acquired to quantify biventricular function. Myocardial iron overload (MIO) was assessed by the T2* technique, while macroscopic myocardial fibrosis was evaluated by the late gadolinium enhancement (LGE) technique. In Sβ-thal and SCA patients, the morphological and functional CMR parameters were not significantly different, except for the left atrial area and left ventricular (LV) stroke volume, indexed by body surface area (p = 0.023 and p = 0.048, respectively), which were significantly higher in SCA patients. No significant differences between the two groups were found in terms of myocardial iron overload and macroscopic myocardial fibrosis. When compared to healthy subjects, Sβ-thal patients showed significantly higher bi-atrial and biventricular parameters, except for LV ejection fraction, which was significantly lower. The CMR analysis confirmed that Sβ-thal and SCA patients are phenotypically similar. Since Sβ-thal patients showed markedly different morphological and functional indices from healthy subjects, it would be useful to identify Sβ-thal/SCA-specific bi-atrial and biventricular reference values.

Changing trends in the prevalence of heart failure impairment with Thalassemias over three decades

BACKGROUND

To assess the prevalence trend and contributing factors of heart failure (HF) impairment with thalassemias at global, regional and national levels.

METHODS

Data on HF impairment with thalassemias was collected from the Global Burden of Disease study. The absolute number and prevalence of the disease were systematically collected for each year, and the estimated annual percentage changes (EAPC) in HF impairment were calculated by gender, region and country to measure temporal trends.

RESULTS

Thalassemias have caused a significant global burden since 1990, and the case number of HF related to thalassemias has been steadily increasing. The highest case number of HF impairments with thalassemias is observed in China (7739 cases) and the highest prevalence is in Pakistan (1.61 per 100,000) currently. Besides, the middle sociodemographic index (SDI) region carries the highest burden of comorbid disease yet exhibits the most evident trend for improvement across the five regions (EAPC = -.98). The burden of thalassemias and comorbid HF is generally higher in males than females with the gender gap growing chasm in the future. Besides, the hotspots of HF impairment with thalassemias have gradually shifted to low SDI regions, though middle SDI regions still hold a relatively higher prevalence (.37 per 100,000) across different regions.

CONCLUSIONS

The burden of thalassemias and accompanying HF, as well as their temporal trends, vary greatly across countries and regions. These findings can improve understanding of these conditions and guide policymakers in developing appropriate policies to address disparities between countries.

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.

Pattern and clinical correlates of renal iron deposition in adult beta-thalassemia major patients

We evaluated pattern and clinical correlates of renal T2* measurements in adult β-thalassemia major (β-TM) patients. Ninety β-TM patients (48 females, 38.15 ± 7.94 years), consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia network, underwent T2* magnetic resonance imaging (MRI) for quantification of iron overload (IO) in kidneys, liver, pancreas, and heart. Ten (11.1%) patients showed renal IO (T2* < 31 ms). Global kidney T2* values did not show a correlation with gender, age, splenectomy, regular transfusions or chelation starting age, pre-transfusion hemoglobin, and serum ferritin levels. Global kidney T2* values showed an inverse correlation with MRI liver iron concentration (LIC) values (R = - 0.349; p = 0.001) and a positive correlation with global pancreas T2* values (R = 0.212; p = 0.045). Frequency of renal IO was significantly higher in patients with cardiac IO than in patients without cardiac IO (50.0% vs. 6.3%; p = 0.001). A significant inverse association was detected between global kidneys T2* values and lactate dehydrogenase (LDH) (R = - 0.529; p < 0.0001). In multivariate regression analysis, MRI LIC and LDH were the strongest predictors of global kidney T2* values. A MRI LIC > 4.83 mg/g dw predicted the presence of renal IO (sensitivity = 90.0%; specificity = 61.2%). Global kidney T2* values were inversely correlated with uric acid (R = - 0.269; p = 0.025). In conclusion, in adult β-TM patients, renal iron deposition is not common and is linked to both hemolysis and total body iron overload.

Prevalence and genetic analysis of triplicated α-globin gene in Ganzhou region using high-throughput sequencing

α-globin gene triplication carriers were not anemic in general, while some studies found that α-globin gene triplication coinherited with heterozygous β-thalassemia may cause adverse clinical symptoms, which yet lacks sufficient evidence in large populations. In this study, we investigated the prevalence and distribution of α-globin gene triplication as well as the phenotypic characteristics of α-globin gene triplication coinherited with heterozygous β-thalassemia in Ganzhou city, southern China. During 2021-2022, a total of 73,967 random individuals who received routine health examinations before marriage were genotyped for globin gene mutations by high-throughput sequencing. Among them, 1,443 were α-globin gene triplication carriers, with a carrier rate of 1.95%. The most prevalent mutation was αααanti3.7/αα (43.10%), followed by αααanti4.2/αα (38.12%). 42 individuals had coinherited α-globin gene triplication and heterozygous β-thalassemia. However, they did not differ from the individuals with heterozygous β-thalassemia and normal α-globin (αα/αα) in terms of mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) levels. In addition, heterogenous clinical phenotypes were found in two individuals with the same genotype. Our study established a database of Ganzhou α-globin gene triplication and provided practical advice for the clinical diagnosis of α-globin gene triplication.

Pancreatic fatty replacement as risk marker for altered glucose metabolism and cardiac iron and complications in thalassemia major

OBJECTIVES

This multicenter study assessed the extent of pancreatic fatty replacement and its correlation with demographics, iron overload, glucose metabolism, and cardiac complications in a cohort of well-treated patients with thalassemia major (TM).

METHODS

We considered 308 TM patients (median age: 39.79 years; 182 females) consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia Network. Magnetic resonance imaging was used to quantify iron overload (IO) and pancreatic fat fraction (FF) by T2* technique, cardiac function by cine images, and to detect replacement myocardial fibrosis by late gadolinium enhancement technique. The glucose metabolism was assessed by the oral glucose tolerance test.

RESULTS

Pancreatic FF was associated with age, body mass index, and history of hepatitis C virus infection. Patients with normal glucose metabolism showed a significantly lower pancreatic FF than patients with impaired fasting glucose (p = 0.030), impaired glucose tolerance (p < 0.0001), and diabetes (p < 0.0001). A normal pancreatic FF (< 6.6%) showed a negative predictive value of 100% for abnormal glucose metabolism. A pancreatic FF > 15.33% predicted the presence of abnormal glucose metabolism. Pancreas FF was inversely correlated with global pancreas and heart T2* values. A normal pancreatic FF showed a negative predictive value of 100% for cardiac iron. Pancreatic FF was significantly higher in patients with myocardial fibrosis (p = 0.002). All patients with cardiac complications had fatty replacement, and they showed a significantly higher pancreatic FF than complications-free patients (p = 0.002).

CONCLUSION

Pancreatic FF is a risk marker not only for alterations of glucose metabolism, but also for cardiac iron and complications, further supporting the close link between pancreatic and cardiac disease.

KEY POINTS

• In thalassemia major, pancreatic fatty replacement by MRI is a frequent clinical entity, predicted by a pancreas T2* < 20.81 ms and associated with a higher risk of alterations in glucose metabolism. • In thalassemia major, pancreatic fatty replacement is a strong risk marker for cardiac iron, replacement fibrosis, and complications, highlighting a deep connection between pancreatic and cardiac impairment.

Pancreatic T2* Magnetic Resonance Imaging for Prediction of Cardiac Arrhythmias in Transfusion-Dependent Thalassemia

We assessed the value of pancreatic T2* magnetic resonance imaging (MRI) for predicting cardiac events from a large prospective database of transfusion-dependent thalassemia (TDT) patients. We considered 813 TDT patients (36.47 ± 10.71 years, 54.6% females) enrolled in the Extension-Myocardial Iron Overload in Thalassemia Network. MRI was used to measure hepatic, pancreatic, and cardiac iron overload (IO), to assess biventricular function and atrial dimensions, and to detect replacement myocardial fibrosis. The mean follow-up was 50.51 ± 19.75 months. Cardiac complications were recorded in 21 (2.6%) patients: one with heart failure (HF) and 20 with arrhythmias. The single patient who developed HF had, at the baseline MRI, a reduced pancreas T2*. Out of the 20 recorded arrhythmias, 17 were supraventricular. Pancreatic T2* values were a significant predictor of future arrhythmia-related events (hazard ratio = 0.89; p = 0.015). Pancreas T2* remained significantly associated with future arrhythmias after adjusting for any other univariate predictor (age and male sex, diabetes, history of previous arrhythmias, or left atrial area index). According to the receiver-operating characteristic curve analysis for arrhythmias, a pancreas T2* < 6.73 ms was the optimal cut-off value. In TDT, pancreatic iron levels had significant prognostic power for arrhythmias. Regular monitoring and the development of targeted interventions to manage pancreatic IO may help improve patient outcomes.

Impact of the COVID-19 Pandemic on Iron Overload Assessment by MRI in Patients with Hemoglobinopathies: The E-MIOT Network Experience

BACKGROUND

The E-MIOT (Extension-Myocardial Iron Overload in Thalassemia) project is an Italian Network assuring high-quality quantification of tissue iron overload by magnetic resonance imaging (MRI). We evaluated the impact of the COVID-19 pandemic on E-MIOT services.

METHODS

The activity of the E-MIOT Network MRI centers in the year 2020 was compared with that of 2019. A survey evaluated whether the availability of MRI slots for patients with hemoglobinopathies was reduced and why.

RESULTS

The total number of MRI scans was 656 in 2019 and 350 in 2020, with an overall decline of 46.4% (first MRI: 71.7%, follow-up MRI: 36.9%), a marked decline (86.9%) in the period March-June 2020, and a reduction in the gap between the two years in the period July-September. A new drop (41.4%) was recorded in the period October-December for two centers, due to the general reduction in the total amount of MRIs/day for sanitization procedures. In some centers, patients refused MRI scans for fear of getting COVID. Drops in the MRI services >80% were found for patients coming from a region without an active MRI site.

CONCLUSIONS

The COVID-19 pandemic had a strong negative impact on MRI multi-organ iron quantification, with a worsening in the management of patients with hemoglobinopathies.

Myocardial tissue characterization by segmental T2 mapping in thalassaemia major: detecting inflammation beyond iron

AIMS

We measured myocardial T2 values by a segmental approach in thalassaemia major (TM) patients, comparing such values against T2* values for the detection of myocardial iron overload (MIO), evaluating their potential in detecting subclinical inflammation, and correlating with clinical status.

METHODS AND RESULTS

One-hundred and sixty-six patients (102 females, 38.29 ± 11.49years) enrolled in the Extension-Myocardial Iron Overload in Thalassemia Network underwent magnetic resonance imaging for the assessment of hepatic, pancreatic, and cardiac iron overload (T2* technique), of biventricular function (cine images), and of replacement myocardial fibrosis [late gadolinium enhancement (LGE)]. T2 and T2* values were quantified in all 16 myocardial segments, and the global value was the mean of all segments. Global heart T2 values were significantly higher in TM than in a cohort of 80 healthy subjects. T2 and T2* values were significantly correlated. Out of the 25 patients with a decreased global heart T2* value, 11 (44.0%) had reduced T2 values. No patient with a normal T2* value had a decreased T2 value.Eleven (6.6%) patients had a decreased global heart T2 value, 74 (44.6%) a normal global heart T2 value, and 81 (48.8%) an increased global heart T2 value. Biventricular function was comparable amongst the three groups, whilst LGE was significantly more frequent in patients with reduced vs. increased global heart T2 value. Compared with the other two groups, patients with reduced T2 values had significantly higher hepatic and pancreatic iron deposition.

CONCLUSION

In TM, T2 mapping does not offer any advantage in terms of sensitivity for MIO assessment but detects subclinical myocardial inflammation.

The impact of HCV chronic positivity and clearance on extrahepatic morbidity in thalassemia major patients: an observational study from MIOT Network

BACKGROUND

No study has evaluated the effect of hepatitis C virus (HCV) infection on the wide spectrum of complications affecting patients with thalassemia.

OBJECTIVES

This multicenter study prospectively assessed the relationship of HCV infection with diabetes mellitus and cardiovascular complications in patients with thalassemia major (TM).

METHODS

We considered 1057 TM patients (539 females; 29.79±10.08 years) enrolled in the MIOT Network and categorized into 4 groups: negative patients (group 1a, N=460), patients who spontaneously cleared the virus within 6months (group 1b, N=242), patients who eradicated the virus after the treatment with antiviral therapy (group 2, N=102), and patients with chronic HCV infection (group 3, N=254).

RESULTS

Group 1a and 1b were considered as a unique group (group 1). For both groups 1 and 3, a match 1:1 for age and sex with group 2 was performed. The effective study cohort consisted of 306 patients (three groups of 102 patients). During a mean follow-up of 67.93±39.20months, the group 3 experienced a significantly higher % increase/month in aspartate transaminase levels and left ventricular mass index than both groups 1 and 2. The changes in iron overload indexes were comparable among the three groups. Compared to group 1, the chronic HCV group showed a significantly higher risk of diabetes (hazard ratio-HR=5.33; p=0.043) and of cardiovascular diseases (HR=3.80; p=0.034).

CONCLUSION

Chronic HCV infection is associated with a significant higher risk of diabetes mellitus and cardiovascular complications in TM patients and should be approached as a systemic disease in which extrahepatic complications increase the weight of its pathological burden.

Medical Radiology: Current Progress

Recently, medical radiology has undergone significant improvements in patient management due to advancements in image acquisition by the last generation of machines, data processing, and the integration of artificial intelligence. In this way, cardiovascular imaging is one of the fastest-growing radiological subspecialties. In this study, a compressive review was focused on addressing how and why CT and MR have gained a I class indication in most cardiovascular diseases, and the potential impact of tissue and functional characterization by CT photon counting, quantitative MR mapping, and 4-D flow. Regarding rectal imaging, advances in cancer imaging using diffusion-weighted MRI sequences for identifying residual disease after neoadjuvant chemoradiotherapy and [18F] FDG PET/MRI were provided for high-resolution anatomical and functional data in oncological patients. The results present a large overview of the approach to the imaging of diffuse and focal liver diseases by US elastography, contrast-enhanced US, quantitative MRI, and CT for patient risk stratification. Italy is currently riding the wave of these improvements. The development of large networks will be crucial to create high-quality databases for patient-centered precision medicine using artificial intelligence. Dedicated radiologists with specific training and a close relationship with the referring clinicians will be essential human factors.

Bone status and HCV infection in thalassemia major patients

PURPOSE

Hepatitis C virus (HCV) infection increases the risk for osteoporosis but this relationship has not been investigated among multi-transfused patients with thalassemia major (TM). We cross-sectionally explored the association of HCV infection with bone mineral density (BMD), vitamin D, and bone turnover biomarkers in TM.

METHODS

We considered 130 TM patients (41.89 ± 5.49 years, 67 females) enrolled in the E-MIOT (Extension-Myocardial Iron Overload in Thalassemia) Network. BMD measurements taken at the lumbar spine, femoral neck and total hip were expressed as Z-scores, with a BMD Z-score ≤ -2.0 indicating low bone mass.

RESULTS

Z-scores were not associated with gender, iron overload indices, vitamin D levels, and biochemical bone turnover markers, but decreased with aging and in presence of hypogonadism and were directly correlated with body mass index (BMI). The prevalence of low bone mass was 70.7 %. Three groups of patients were identified: 78 who never contracted the infection (group 0), 72 who cleared HCV (group 1), and 29 with chronic HCV infection (CHC) (group 2). All Z-scores progressively decreased according to HCV status from group 0 to group 2. Osteocalcin levels were significantly lower in groups 2 and 1 than in group 0. CHC patients were more likely to have low bone mass compared to HCV naive patients, after adjusting for age, BMI, hypogonadism, and pancreatic iron.

CONCLUSION

In TM, CHC appears as one additive risk factor for low bone mass and osteocalcin may play a role in this association.

Left Ventricle Detection from Cardiac Magnetic Resonance Relaxometry Images Using Visual Transformer

Left Ventricle (LV) detection from Cardiac Magnetic Resonance (CMR) imaging is a fundamental step, preliminary to myocardium segmentation and characterization. This paper focuses on the application of a Visual Transformer (ViT), a novel neural network architecture, to automatically detect LV from CMR relaxometry sequences. We implemented an object detector based on the ViT model to identify LV from CMR multi-echo T2* sequences. We evaluated performances differentiated by slice location according to the American Heart Association model using 5-fold cross-validation and on an independent dataset of CMR T2*, T2, and T1 acquisitions. To the best of our knowledge, this is the first attempt to localize LV from relaxometry sequences and the first application of ViT for LV detection. We collected an Intersection over Union (IoU) index of 0.68 and a Correct Identification Rate (CIR) of blood pool centroid of 0.99, comparable with other state-of-the-art methods. IoU and CIR values were significantly lower in apical slices. No significant differences in performances were assessed on independent T2* dataset (IoU = 0.68, p = 0.405; CIR = 0.94, p = 0.066). Performances were significantly worse on the T2 and T1 independent datasets (T2: IoU = 0.62, CIR = 0.95; T1: IoU = 0.67, CIR = 0.98), but still encouraging considering the different types of acquisition. This study confirms the feasibility of the application of ViT architectures in LV detection and defines a benchmark for relaxometry imaging.

Development of a Thalassemia International Prognostic Scoring System (TIPSS)

A prognostic scoring system that can differentiate β-thalassemia patients based on mortality risk is lacking. We analysed data from 3145 β-thalassemia patients followed through a retrospective cohort design for the outcome of death. An a priori list of prognostic variables was collected. β Coefficients from a multivariate cox regression model were used from a development dataset (n = 2516) to construct a formula for a Thalassemia International Prognostic Scoring System (TIPSS) which was subsequently applied to a validation dataset (n = 629). The median duration of observation was 10.0 years. The TIPSS score formula was constructed as exp (1.4 × heart disease + 0.9 × liver disease + 0.9 × diabetes + 0.9 × sepsis + 0.6 × alanine aminotransferase ≥42 IU/L + 0.6 × hemoglobin ≤9 g/dL + 0.4 × serum ferritin ≥1850 ng/mL). TIPSS score thresholds of greatest differentiation were assigned as <2.0 (low-risk), 2.0 to <5.0 (intermediate-risk), and ≥5.0 (high-risk). The TIPSS score was a good predictor for the outcome of death in the validation dataset (AUC: 0.722, 95%CI: 0.641-0.804) and survival was significantly different between patients in the three risk categories (P < 0.001). Compared to low-risk patients, the hazard ratio for death was 2.778 (95%CI: 1.335-5.780) in patients with intermediate-risk and 6.431 (95%CI: 3.151-13.128) in patients with high-risk. This study provides a novel tool to support mortality risk categorization for patients with β-thalassemia that could help management and research decisions.

Multi-Parametric Cardiac Magnetic Resonance for Prediction of Heart Failure Death in Thalassemia Major

We assessed the prognostic value of multiparametric cardiovascular magnetic resonance (CMR) in predicting death from heart failure (HF) in thalassemia major (TM). We considered 1398 white TM patients (30.8 ± 8.9 years, 725 women) without a history of HF at baseline CMR, which was performed within the Myocardial Iron Overload in Thalassemia (MIOT) network. Iron overload was quantified by using the T2* technique, and biventricular function was determined with cine images. Late gadolinium enhancement (LGE) images were acquired to detect replacement myocardial fibrosis. During a mean follow-up of 4.83 ± 2.05 years, 49.1% of the patients changed the chelation regimen at least once; these patients were more likely to have significant myocardial iron overload (MIO) than patients who maintained the same regimen. Twelve (1.0%) patients died from HF. Significant MIO, ventricular dysfunction, ventricular dilation, and replacement myocardial fibrosis were identified as significant univariate prognosticators. Based on the presence of the four CMR predictors of HF death, patients were divided into three subgroups. Patients having all four markers had a significantly higher risk of dying for HF than patients without markers (hazard ratio (HR) = 89.93; 95%CI = 5.62-1439.46; p = 0.001) or with one to three CMR markers (HR = 12.69; 95%CI = 1.60-100.36; p = 0.016). Our findings promote the exploitation of the multiparametric potential of CMR, including LGE, for better risk stratification for TM patients.

Increased myocardial extracellular volume is associated with myocardial iron overload and heart failure in thalassemia major

OBJECTIVES

Myocardial extracellular volume (ECV) by cardiovascular magnetic resonance (CMR) is a surrogate marker of diffuse fibrosis. We evaluated the association between ECV and demographics, CMR findings, and cardiac involvement in patients with thalassemia major (TM).

METHODS

A total of 108 β-TM patients (62 females, 40.16 ± 8.83 years), consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia Network, and 16 healthy subjects (6 females, 37.12 ± 16.13 years) underwent CMR. The protocol included assessment of T2*, native T1, and T2 values in all 16 myocardial segments for myocardial iron overload (MIO) quantification, cine images for left ventricular (LV) function quantification, post-contrast T1 mapping for ECV calculation, and late gadolinium enhancement (LGE) technique for replacement myocardial fibrosis detection.

RESULTS

Global ECV values were significantly higher in females than in males. Global ECV values were significantly higher in patients with significant MIO (global heart T2* < 20 ms) than in patients without significant MIO, and both groups exhibited higher global ECV values than healthy subjects. No association was detected between native T1 and ECV values, while patients with reduced global heart T2 values showed significantly higher global ECV values than patients with normal and increased global heart T2. Global ECV values were not correlated with LV function/size and were comparable between patients with and without LGE. Compared to patients without heart failure, patients with a history of heart failure (N = 10) showed significantly higher global heart ECV values.

CONCLUSION

In TM, increased myocardial ECV, potentially reflecting diffuse interstitial fibrosis, is associated with MIO and heart failure.

KEY POINTS

• CMR-derived myocardial extracellular volume is increased in thalassemia major patients, irrespective of the presence of late gadolinium enhancement. • In thalassemia major, myocardial iron overload contributes to the increase in myocardial ECV, which potentially reflects diffuse interstitial fibrosis and is significantly associated with a history of heart failure.

Left ventricular global function index is associated with myocardial iron overload and heart failure in thalassemia major patients

PURPOSE

The left ventricular global function index (LVGFI) is a comprehensive marker of cardiac performance, integrating LV morphology with global function. We explored the cross-sectional association of LVGFI with myocardial iron overload (MIO), LV ejection fraction (LVEF), myocardial fibrosis, and heart failure (HF) in β-thalassemia major (TM) patients.

METHODS

We considered 1352 adult TM patients (708 females, 32.79 ± 7.16years) enrolled in the Myocardial Iron Overload in Thalassemia Network and 112 healthy subjects (50 females, 32.09 ± 6.08years). LVGFI and LVEF were assessed by cine images and MIO by multislice multiecho T2* technique. Replacement myocardial fibrosis was detected by late gadolinium enhancement technique.

RESULTS

LVGFI and LVEF were significantly lower in patients with significant MIO (global heart T2*<20ms) than in patients without MIO and in healthy subjects but were comparable between TM patients without MIO and healthy subjects. In TM, LVGFI was significantly associated with LVEF (R = 0.733; p < 0.0001). Global heart T2* values were significantly associated with both LVGFI and LVEF, but the correlation with LVGFI was significantly stronger (p = 0.0001). Male sex, diabetes mellitus, significant MIO, and replacement myocardial fibrosis were the strongest predictors of LVGFI. Eighty-six patients had a history of HF and showed significantly lower global heart T2* values, LVEF, and LVGFI than HF-free patients. A LVGFI ≤ 44.9% predicted the presence of HF. The LVGFI showed a diagnostic performance superior to that of LVEF (area under the curve: 0.67 vs. 0.62; p = 0.039).

CONCLUSION

In TM patients the LVGFI correlates with MIO and provides incremental diagnostic value for HF detection compared with LVEF.

TIF Standards for Haemoglobinopathy Reference Centres

Haemoglobin disorders are hereditary, lifelong and characterised by the need for multifaceted management. The question of quality in meeting standards of care that are likely to bring the best possible outcomes for patients is a necessary consideration. The concept of reference centres supporting peripheral treatment centres in a formal networking relationship is a response to the real needs of patients and a practical solution in public health terms. In this report, a team of advisors of Thalassaemia International Federation (TIF) attempts to suggest a set of standards for haemoglobinopathy reference centres, also based on the founding principles of TIF, aiming to act as a guideline for its member associations and professional collaborators. The standards described herein can form the basis of an accreditation process and also serve as a guide for those who would advocate for quality improvement for thalassaemia services.

Gender Differences in Knowledge and Perception of Cardiovascular Disease among Italian Thalassemia Major Patients

We evaluated gender differences in knowledge and perception of cardiovascular disease (CVD) among Italian thalassemia major (TM) patients. An anonymous questionnaire was completed by 139 β-TM patients (87 (62.7%) females, 40.90 ± 8.03 years). Compared to females, males showed a significantly higher frequency of CVDs, and they less frequently selected tumors in general as the greatest health problem for people of the same age and gender (48.1% vs. 66.7%; p = 0.031) and as the greatest danger to their future health (26.9% vs. 43.7%; p = 0.048). CVDs were designated as the greatest danger to their future health by a significantly higher percentage of males than females (53.8% vs. 36.8%; p = 0.048). Both males and females showed a good knowledge of cardiovascular risk factors and preventive measures for CVDs. No gender differences were detected in the subjective well-being and the perceived cardiovascular risk. The perceived risk was not influenced by age, presence of cardiovascular risk factors, or disease, but no patient with a low perceived CVD risk had myocardial iron overload. Our findings highlight the need to implement future educational programs aimed at increasing the awareness of CVD as the greatest health issue, especially among the female TM population, and at informing TM patients of the different actors, besides iron, that play a role in the development of cardiovascular complications.

Link between Genotype and Multi-Organ Iron and Complications in Children with Transfusion-Dependent Thalassemia

We evaluated the impact of the genotype on hepatic, pancreatic and myocardial iron content, and on hepatic, cardiac and endocrine complications in children with transfusion-dependent β-thalassemia (β-TDT). We considered 68 β-TDT patients (11.98 ± 3.67 years, 51.5% females) consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia network. Iron overload was quantified by T2* technique and biventricular function by cine images. Replacement myocardial fibrosis was evaluated by late gadolinium enhancement technique. Three groups of patients were identified: homozygous β+ (N = 19), compound heterozygous β0β+ (N = 24), and homozygous β0 (N = 25). The homozygous β0 group showed significantly lower global heart and pancreas T2* values than the homozygous β+ group. Compared to patients with homozygous β+ genotype, β0β+ as well as β0β0 patients were more likely to have pancreatic iron overload (odds ratio = 6.53 and 10.08, respectively). No difference was detected in biventricular function parameters and frequency of replacement fibrosis. No patient had cirrhosis/fibrosis, diabetes or heart failure, and the frequency of endocrinopathies was comparable among the groups. In pediatric β-TDT patients, there is an association between genotype and cardiac and pancreatic iron overload. The knowledge of patients’ genotype can be valuable in predicting some patients’ phenotypic features and in helping the clinical management of β-TDT patients.

Random Forest Clustering Identifies Three Subgroups of β-Thalassemia with Distinct Clinical Severity

In this work, we aimed to establish subgroups of clinical severity in a global cohort of β-thalassemia through unsupervised random forest (RF) clustering. We used a large global dataset of 7910 β-thalassemia patients and evaluated 19 indicators of phenotype severity (IPhS) to determine their contribution and relatedness in grouping β-thalassemia patients into clusters using RF analysis. RF clustering suggested that three clusters with minimal overlapping exist (classification error rate: 4.3%), and six important IPhS were identified: the current age of the patient, the mean serum ferritin level, the age at diagnosis, the age at first transfusion, the age at first iron chelation, and the number of complications. Cluster 3 represented patients with early initiation of transfusion and iron chelation, considerable iron overload, and early mortality from heart failure. Patients in Cluster 2 had lower serum ferritin levels, although they had a higher number of complications manifesting overtime. Patients in Cluster 1 represented a subgroup with delayed or absent transfusion and iron chelation, but with a high morbidity rate. Hepatic disease and cancer were dominant causes of death in patients in Cluster 1 and 2. Our findings established that patients with β-thalassemia can be clustered into three groups based on six parameters of phenotype severity.