Cardiovascular T2-star (T2*) magnetic resonance for the early diagnosis of myocardial iron overload

Prognostic Role of Multiparametric Cardiac Magnetic Resonance in Neo Transfusion-Dependent Thalassemia

BACKGROUND

We prospectively evaluated the predictive value of multiparametric cardiac magnetic resonance (CMR) for cardiovascular complications in non-transfusion-dependent β-thalassemia (β-NTDT) patients who started regular transfusions in late childhood/adulthood (neo β-TDT).

METHODS

We considered 180 patients (38.25 ± 11.24 years; 106 females). CMR was used to quantify cardiac iron overload, biventricular function, and atrial dimensions, and to detect left ventricular (LV) replacement fibrosis.

RESULTS

During a mean follow-up of 76.87 ± 41.60 months, 18 (10.0%) cardiovascular events were recorded: 2 heart failures, 13 arrhythmias (10 supraventricular), and 3 cases of pulmonary hypertension. Right ventricular (RV) end-diastolic volume index (EDVI), RV mass index (MI), LV replacement fibrosis, and right atrial (RA) area index emerged as significant univariate prognosticators of cardiovascular complications. The low number of events prevented us from performing a multivariable analysis including all univariable predictors simultaneously. Firstly, a multivariable analysis including the two RV size parameters (mass and volume) was carried out, and only the RV MI was proven to independently predict cardiovascular diseases. Then, a multivariable analysis, including RV MI, RA atrial area, and LV replacement fibrosis, was conducted. In this model, RV MI and LV replacement fibrosis emerged as independent predictors of cardiovascular outcomes (RV MI: hazard ratio (HR) = 1.18; LV replacement fibrosis: HR = 6.26).

CONCLUSIONS

Our results highlight the importance of CMR in cardiovascular risk stratification.

Luspatercept stimulates erythropoiesis, increases iron utilization, and redistributes body iron in transfusion-dependent thalassemia

Luspatercept, a ligand-trapping fusion protein, binds select TGF-β superfamily ligands implicated in thalassemic erythropoiesis, promoting late-stage erythroid maturation. Luspatercept reduced transfusion burden in the BELIEVE trial (NCT02604433) of 336 adults with transfusion-dependent thalassemia (TDT). Analysis of biomarkers in BELIEVE offers novel physiological and clinical insights into benefits offered by luspatercept. Transfusion iron loading rates decreased 20% by 1.4 g (~7 blood units; median iron loading rate difference: -0.05 ± 0.07 mg Fe/kg/day, p< .0001) and serum ferritin (s-ferritin) decreased 19.2% by 269.3 ± 963.7 μg/L (p < .0001), indicating reduced macrophage iron. However, liver iron content (LIC) did not decrease but showed statistically nonsignificant increases from 5.3 to 6.7 mg/g dw. Erythropoietin, growth differentiation factor 15, soluble transferrin receptor 1 (sTfR1), and reticulocytes rose by 93%, 59%, 66%, and 112%, respectively; accordingly, erythroferrone increased by 51% and hepcidin decreased by 53% (all p < .0001). Decreased transfusion with luspatercept in patients with TDT was associated with increased erythropoietic markers and decreasing hepcidin. Furthermore, s-ferritin reduction associated with increased erythroid iron incorporation (marked by sTfR1) allowed increased erythrocyte marrow output, consequently reducing transfusion needs and enhancing rerouting of hemolysis (heme) iron and non-transferrin-bound iron to the liver. LIC increased in patients with intact spleens, consistent with iron redistribution given the hepcidin reduction. Thus, erythropoietic and hepcidin changes with luspatercept in TDT lower transfusion dependency and may redistribute iron from macrophages to hepatocytes, necessitating the use of concomitant chelator cover for effective iron management.

Two risk factors for hypozincemia in diabetic β-thalassemia patients: Hepatitis C and deferasirox

BACKGROUND AND AIM

Hypozincemia is a prevalent adverse consequence in diabetes mellitus (DM) and β-Thalassemia patients. We aimed to evaluate the level of serum zinc in β-thalassemia patients with DM and a risk assessment for hypozincemia.

METHODS

The study population included transfusion-dependent thalassemia (TDT) and non-transfusion-dependent thalassemia (NTDT) with overt DM (fasting plasma glucose (FPG) ≥126 mg/dL, and/or 2-h plasma glucose≥200 mg/dL). Serum zinc concentration was measured by the colorimetric method, and the values below 70 μg/dL were defined as hypozincemia. Myocardial and liver T2*-weighted magnetic resonance imaging (MRI T2*, millisecond [ms]) were valued by a free contrast MRI. The demographic, clinical, paraclinical, and laboratory data were also recorded. The data belonged to the period from December 2018 until December 2020.

RESULTS

Of 64 diabetic β-thalassemia patients, 41 cases had zinc data in their medical files (aged 38 ± 9 years, 48.8% female). 78.05% of patients (n = 32) were TDT, and 21.95% were NTDT (n = 9). The mean ± standard deviation of zinc level was 110.2 ± 127.6 μg/dL. The prevalence of hypozincemia was 9.76%, 95% confidence interval [CI] 0.27 to 19.24 (four cases). After controlling age, the odds of hypozincemia for using deferasirox (DFX) was 8.77, 95% CI 0.60 to 127.1. In β-thalassemia patients, the age-adjusted risk of hypozincemia was calculated at 15.85, 95% CI 0.47 to 529.3 for hepatitis C. The adjusted risk of hypozincemia based on age for antacid use was 6.34, 95% CI 0.39 to 102.7.

CONCLUSION

In light of this study, as well as hepatitis C, using DFX and antacids is associated with a high risk of hypozincemia amid diabetic β-thalassemia cases. However, upward bias should be taken into consideration.

Efficacy and Safety of a Dispersible Tablet of GPO-Deferasirox Monotherapy among Children with Transfusion-Dependent Thalassemia and Iron Overload

The study aimed to determine efficacy and safety of generic deferasirox monotherapy. Deferasirox was administered in transfusion-induced iron overloaded thalassemia. Efficacy was defined as responders and nonresponders by ≤ 15 reduced serum ferritin from baseline. Adverse events were also monitored. Fifty-two patients with mainly Hb E/β-thalassemia at the mean (SD) age of 8.7 (4.1) years, were enrolled. The mean (SD) daily transfusion iron load was 0.47 (0.1) mg/kg and maximum daily deferasirox was 35.0 (6.2) mg/kg. Altogether, 52, 40 and 18 patients completed the first, second and third years of study, respectively. The median baseline serum ferritin 2,383 ng/mL decreased to 1,478, 1,038 and 1,268 ng/mL at the end of first, second and third years, respectively, with overall response rate at 73.1% (38/52). Patients with baseline serum ferritin >2,500 ng/mL showed a change in serum ferritin higher than those ≤2,500 ng/mL starting from the 9th month of chelation. Adverse events were found in 5 of 52 patients (9.6%) including transaminitis (n = 2), one each of proteinuria, rash and proximal tubular dysfunction which resolved after transient stopping or decreasing the chelation dose. Generic deferasirox was effective and safe among pediatric patients with transfusion-induced iron overloaded thalassemia.

Assessment of early anthracycline-induced cardiotoxicity and liver injury with T2 and T2* mapping in rabbit models

OBJECTIVES

To evaluate the early prevalence of anthracycline-induced cardiotoxicity (AIC) and anthracycline-induced liver injury (AILI) using T2 and T2* mapping and to explore their correlations.

MATERIALS AND METHODS

The study included 17 cardiotoxic rabbits that received weekly injections of doxorubicin and magnetic resonance imaging (MRI) every 2 weeks for 10 weeks. Cardiac function and T2 and T2* values were measured on each period. Histopathological examinations for two to five rabbits were performed after each MRI scan. The earliest sensitive time and the threshold of MRI parameters for detecting AIC and AILI based on these MRI parameters were obtained. Moreover, the relationship between myocardial and liver damage was assessed.

RESULTS

Early AIC could be detected by T2 mapping as early as the second week and focused on the 7th, 11th, and 12th segments of left ventricle. The cutoff value of 46.64 for the 7th segment had the best diagnostic value, with an area under the curve (of 0.767, sensitivity of 100%, and specificity of 52%. T2* mapping could detect the change in iron content for early AIC at the middle interventricular septum and AILI as early as the sixth week (p = 0.014, p = 0.027). The T2* values of the middle interventricular septum showed a significant positive association with the T2* values of the liver (r = 0.39, p = 0.002).

CONCLUSION

T2 and T2* mapping showed value one-stop assessment of AIC and AILI and could obtain the earliest MRI diagnosis point and optimal parameter thresholds for these conditions.

CLINICAL RELEVANCE STATEMENT

Anthracycline-induced cardiotoxicity could be detected by T2 mapping as earlier as the second week, mainly focusing on the 7th, 11th, and 12th segments of left ventricle. Combined with T2* mapping, hepatoxicity and supplementary cardiotoxicity were assessed by one-stop scan.

KEY POINTS

• MRI screening time of cardiotoxicity was as early as the second week with focusing on T2 values of the 7th, 11th, and 12th segments of left ventricle. • T2* mapping could be used as a complement to T2 mapping to evaluate cardiotoxicity and as an effective index to detect iron change in the early stages of chemotherapy. • The T2* values of the middle interventricular septum showed a significant positive association with the T2* values of the liver, indicating that iron content in the liver and heart increased with an increase in the chemotherapeutic drugs.

On the loss of image contrast in double-inversion-recovery prepared T2* MRI of Intramyocardial hemorrhage

PURPOSE

Studies have shown that double-inversion-recovery (DIR) prepared dark-blood T2*-weighted images result in lower SNR, CNR and diagnostic accuracy for intramyocardial hemorrhage (IMH) detection compared to non-DIR-prepared (bright-blood) T2*-weighted images; however, the mechanism contributing to this observation has not been investigated and explained in detail. This work tests the hypothesis that the loss of SNR on dark-blood cardiac T2*-weighted images of IMH stems from spin-relaxation during the long RF pulses in double inversion preparation, as a result, compromising image contrast for intramyocardial hemorrhage detection.

METHODS

Phantom and in-vivo animal studies were performed to test the hypothesis of the study. An agar phantom was imaged with multi-gradient-echo T2* imaging protocols with and without double-inversion-recovery (DIR) preparation. Image acquisitions were placed at different delay times (TD) after DIR preparation. SNR, T2* and Coefficient of Variation (COV) were measured and compared between DIR-prepared and non-DIR-prepared images. Canines with hemorrhagic myocardial infarctions were scanned at 3.0 T with DIR-prepared (dark-blood) and non-DIR-prepared (bright-blood) T2* imaging protocols. DIR-prepared T2* images were acquired with short, medium, and long delay times (TD). SNR, CNR, intramyocardial hemorrhage (IMH) extent, T2* and COV were measured and compared between DIR-prepared T2* images with short, medium, and long delay times (TD) to non-DIR-prepared bright-blood T2* images.

RESULTS

Phantom studies confirmed the hypothesis that the SNR loss on DIR-prepared T2* images originated from signal loss during DIR preparation. SNR followed T1 recovery curve with increased delay times (TD) indicating that SNR can be recovered with longer time delay between DIR and image acquisition. Myocardial T2* values were not affected by DIR preparation but COV of T2* was elevated. Animal studies supported the hypothesis and showed that DIR-prepared T2* images with insufficient delay time (TD) had impaired sensitivity for IMH detection due to lower SNR and CNR, and higher COV.

CONCLUSION

We conclude that lower SNR and CNR on DIR-prepared T2* images originate from signal loss during DIR preparation and insufficient recovery between DIR preparation and image acquisition. Although, the impaired sensitivity can be recovered by extending delay time (TD), it will extend the scan time. Bright-blood T2* imaging protocols should remain the optimal choice for assessment of intramyocardial hemorrhage. DIR-prepared dark-blood T2* imaging protocols should be performed with extra attention on image signal-to-noise ratio when used for intramyocardial hemorrhage detection.

Clinical and genetic predictors of cardiac dysfunction assessed by echocardiography in patients with hereditary hemochromatosis

PURPOSE

Hereditary hemochromatosis (HH) may cause iron deposition in cardiac tissue. We aimed to describe the echocardiographic findings in patients with HH and identify risk factors for cardiac dysfunction.

METHODS

In this retrospective study, we included patients with HH who underwent transthoracic echocardiography at our tertiary care center between August 2000 and July 2022. We defined three primary outcomes for cardiac dysfunction: 1) left ventricular ejection fraction (LVEF) < 55%, 2) ratio between early mitral inflow velocity and mitral annular early diastolic velocity (E/e') > 15, and 3) global longitudinal strain (GLS) < 18. Multivariable logistic regression was utilized to identify predictors of cardiac dysfunction.

RESULTS

582 patients (median age 57 years, 61.2% male) were included. The frequency of LVEF < 55%, E/e' > 15 and GLS < 18 was 9.0% (52/580), 9.6% (51/534) and 20.2% (25/124), respectively. In multivariable analysis, non-White race, age, and hypertension were associated with E/e' > 15. No specific HFE genetic mutation was associated with LVEF < 55%. A history of myocardial infarction was strongly associated with both LVEF < 55% and E/e' > 15. In patients with LVEF ≥ 55%, the C282Y/H63D genetic mutation was associated with reduced likelihood of E/e' > 15, p = 0.024. Patients with C282Y/H63D had a higher frequency of myocardial infarction. Smoking and alcohol use were significantly associated with GLS < 18 in unadjusted analysis.

CONCLUSION

We found the traditional risk factors of male sex, and history of myocardial infarction or heart failure, were associated with a reduced LVEF, irrespective of the underlying HFE genetic mutation. Patients with a C282Y/H63D genetic mutation had a higher frequency of myocardial infarction, yet this mutation was associated with reduced odds of diastolic dysfunction compared to other genetic mutations in patients with a normal LVEF.

Diagnostic Value of T1 Mapping in Detecting Iron Overload in Indian Patients with Thalassemia Major: A Comparison with T2* Mapping

Purpose  T2* is the gold standard for iron quantification in liver as well as myocardium. In this study, we evaluated the diagnostic accuracy of myocardial T1 mapping for the assessment of myocardial iron overload (MIO) as compared to the T2* mapping in patients with thalassemia major (TM). Methods  Consecutive TM patients attending the thalassemia clinic were prospectively enrolled. Magnetic resonance imaging was performed on a 1.5 T scanner (Siemens Healthineers, Germany) using a gradient echo T2* as well as a T1 mapping (MOLLI) sequence done at a mid-ventricular short-axis single 8 mm slice of the left ventricle. Values were analyzed by manually drawing a region of interest in the mid-septum. T2*less than 20ms was used as the cutoff for significant MIO. Results  One-hundred three patients (58 males, mean age: 17 ± 7.8 years, mean ferritin: 2009.5 µg/L) underwent cardiovascular magnetic resonance. Median T2* of myocardium was 33.45ms. Nineteen patients (18.4%) had T2*less than 20ms. T1 value was low (<850ms) in all the patients with T2* less than 20 ms. Receiver operating characteristic curve analysis revealed the best cutoff of native T1 mapping value as 850 ms which had high specificity (95.2%), sensitivity (94.2%) and negative predictive value (98.8%) for T2* less than 20ms. There was excellent agreement between T1 and T2* for diagnosis of MIO (Kappa-0.848, p <0.001). We did not find any patient who had normal T1 mapping values but had MIO on T2*. Conclusion  T1 and T2* correlate well and normal T1 values may rule out presence of MIO. T1 mapping can act as additional imaging marker for MIO and may be helpful in centers with nonavailability or limited experience of T2*.

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.

Cardiac magnetic resonance biomarkers as surrogate endpoints in cardiovascular trials for myocardial diseases

Cardiac magnetic resonance offers multiple facets in the diagnosis, risk stratification, and management of patients with myocardial diseases. Particularly, its feature to precisely monitor disease activity lends itself to quantify response to novel therapeutics. This review critically appraises the value of cardiac magnetic resonance imaging biomarkers as surrogate endpoints for prospective clinical trials. The primary focus is to comprehensively outline the value of established cardiac magnetic resonance parameters in myocardial diseases. These include heart failure, cardiac amyloidosis, iron overload cardiomyopathy, hypertrophic cardiomyopathy, cardio-oncology, and inflammatory cardiomyopathies like myocarditis and sarcoidosis.

Cardiac MRI-Based Assessment of Myocardial Injury in Asymptomatic People Living With Human Immunodeficiency Virus: Correlation With nadir CD4 Count

BACKGROUND

There are known cardiac manifestations of HIV, but the findings in asymptomatic subjects are still not fully explored.

PURPOSE

To evaluate for the presence of subclinical myocardial injury in asymptomatic people living with human immunodeficiency virus (PLWH) by cardiac MRI and to explore the possible association between subclinical myocardial injury and HIV-related clinical characteristics.

STUDY TYPE

Cross-sectional.

POPULATION

A total of 80 asymptomatic PLWH (age: 53 years [47-56 years]; 90% male) and 50 age- and sex-matched healthy participants.

FIELD STRENGTH/SEQUENCE

A 3-T, cine sequence, T1, T2, and T2* mapping.

ASSESSMENT

Function analysis was derived from short axis, two-, three-, and four-chamber cine images by feature tracking. Regions of interest were manually selected in the midventricular septum T1, T2, and T2* mapping sequences. PLWH were evaluated for T1 increment (△T1 mapping = native T1 - cutoff values) and HIV-related clinical characteristics, particularly the nadir CD4 count. And PLWH were stratified into two groups according to the cutoff value of native T1: elevated native T1 and normal.

STATISTICAL TESTS

T test, Wilcoxon rank-sum test, Chi-square test, Spearman rank correlation, and logistic regression. P <0.05 indicated statistical significance.

RESULTS

Asymptomatic PLWH revealed significantly higher native myocardial T1 values (1241 ± 29 msec vs. 1189 ± 21 msec), T2 values (40.7 ± 1.5 msec vs. 37.9 ± 1.4 msec), and lower LVGRS (30.2% ± 6.2% vs. 35.8% ± 6.4%), LVGCS (-18.0% ± 2.5% vs. -19.5% ± 2.0%), and LVGLS (-16.0% ± 3.8% vs. -17.9% ± 2.6%) but showed no difference in T2* values (17.3 msec [16.3-19.1 msec] vs. 18.3 msec [16.5-19.3 msec], P = 0.201). A negative correlation between the native T1 increment in PLWH with subclinical myocardial injury and the nadir CD4 count (u = -0.316). Nadir CD4 count <500 cells/mm3 was associated with higher odds of elevated native T1 myocardial values (odds ratio, 6.12 [95% CI, 1.07-34.91]) in PLWH.

DATA CONCLUSION

Subclinical myocardial inflammation and dysfunction were present in asymptomatic PLWH, and a lower nadir CD4 count may be a risk factor for subclinical myocardial injury.

EVIDENCE LEVEL

1.

TECHNICAL EFFICACY

Stage 2.

Cardiac complications in thalassemia throughout the lifespan: Victories and challenges

Thalassemias are among the most common hereditary diseases in the world because heterozygosity offers protection against malarial infection. Affected individuals have variable expression of alpha or beta chains that lead to their unbalanced utilization during hemoglobin formation, oxidative stress, and apoptosis of red cell precursors prior to maturation. Some individuals produce sufficient hemoglobin to survive but suffer the vascular stress imposed by chronic anemia and ineffective erythropoiesis. In other patients, mature red cell formation is insufficient, and chronic transfusions are required-suppressing anemia and ineffective erythropoiesis but at the expense of iron overload. The cardiovascular consequences of thalassemia have changed dramatically over the previous five decades because of evolving treatment practices. This review summarizes this evolution, focusing on complications and management pertinent to modern patient cohorts.

Drug Selection and Posology, Optimal Therapies and Risk/Benefit Assessment in Medicine: The Paradigm of Iron-Chelating Drugs

The design of clinical protocols and the selection of drugs with appropriate posology are critical parameters for therapeutic outcomes. Optimal therapeutic protocols could ideally be designed in all diseases including for millions of patients affected by excess iron deposition (EID) toxicity based on personalised medicine parameters, as well as many variations and limitations. EID is an adverse prognostic factor for all diseases and especially for millions of chronically red-blood-cell-transfused patients. Differences in iron chelation therapy posology cause disappointing results in neurodegenerative diseases at low doses, but lifesaving outcomes in thalassemia major (TM) when using higher doses. In particular, the transformation of TM from a fatal to a chronic disease has been achieved using effective doses of oral deferiprone (L1), which improved compliance and cleared excess toxic iron from the heart associated with increased mortality in TM. Furthermore, effective L1 and L1/deferoxamine combination posology resulted in the complete elimination of EID and the maintenance of normal iron store levels in TM. The selection of effective chelation protocols has been monitored by MRI T2* diagnosis for EID levels in different organs. Millions of other iron-loaded patients with sickle cell anemia, myelodysplasia and haemopoietic stem cell transplantation, or non-iron-loaded categories with EID in different organs could also benefit from such chelation therapy advances. Drawbacks of chelation therapy include drug toxicity in some patients and also the wide use of suboptimal chelation protocols, resulting in ineffective therapies. Drug metabolic effects, and interactions with other metals, drugs and dietary molecules also affected iron chelation therapy. Drug selection and the identification of effective or optimal dose protocols are essential for positive therapeutic outcomes in the use of chelating drugs in TM and other iron-loaded and non-iron-loaded conditions, as well as general iron toxicity.

Magnetic resonance imaging assessment of the changes of cardiac and hepatic iron load in thalassemia patients before and after hematopoietic stem cell transplantation

To investigate the value of T2* technique on 3.0 T magnetic resonance imaging (MRI) in evaluating the changes of cardiac and hepatic iron load before and after hematopoietic stem cell transplantation (HSCT) in patients with thalassemia (TM), the 141 TM patients were divided into 6 group for subgroup analysis: 6, 12, 18, 24 and > 24 months group, according to the postoperative interval. The T2* values of heart and liver (H-T2*, L-T2*) were quantified in TM patients before and after HSCT using 3.0 T MRI T2* technology, and the corresponding serum ferritin (SF) was collected at the same time, and the changes of the three before and after HSCT were compared. The overall H-T2* (P = 0.001) and L-T2* (P = 0.041) of patients after HSCT were higher than those before HSCT (mean relative changes = 19.63%, 7.19%). The H-T2* (P < 0.001) and L-T2* (P < 0.001) > 24 months after HSCT were significantly higher than those before HSCT (mean relative changes = 69.19%, 93.73%). The SF of 6 months (P < 0.001), 12 months (P = 0.008), 18 months (P = 0.002) and > 24 months (P = 0.001) were significantly higher than those before HSCT (mean relative changes = 57.93%, 73.84%, 128.51%, 85.47%). There was no significant improvement in cardiac and liver iron content in TM patients within 24 months after HSCT, while the reduction of cardiac and liver iron content in patients is obvious when > 24 months after HSCT.

Raynaud phenomenon and microvasculopathy in systemic sclerosis: multi-modality imaging for diagnosis and evaluation

PURPOSE OF REVIEW

To describe the clinical significance of and the diagnostic approach to Raynaud phenomenon (RP) in the peripheral extremities and the heart.

RECENT FINDINGS

Nailfold capillaroscopy has recently been standardized in an expert consensus paper. Abnormal capillaroscopy in combination with specific autoantibody profiles and clinical signs are highly predictive of progression of RP to systemic sclerosis (SSc). Magnetic resonance imaging (MRI) can also perform tissue characterization of both the extremities and the heart. Microvascular wall abnormalities detected using nailfold capillaroscopy in patients with SSc may lead to deposition of erythrocyte-derived iron, due to microhemorrhages, which may predispose to fibrosis. MRI can assess the presence of iron using T2∗ measurements.

SUMMARY

RP is a hallmark of the microvasculopathy in SSc and can affect both the peripheral extremities and the heart. Nailfold capillaroscopy is the current gold standard for the evaluation of the peripheral microvasculature. Other imaging modalities include thermography, laser Doppler-derived methods, 99m Tc-pertechnetate hand perfusion scintigraphy, power Doppler ultrasonography, dynamic optical coherence tomography, MRI, and photoacoustic imaging, but these are currently not widely used. Cardiac RP can be investigated with positron emission tomography or cardiovascular magnetic resonance, with the latter offering the additional possibility of tissue characterization and iron content quantification secondary to microhemorrhages.

Secondary Hemochromatosis Leading to Acute Coronary Syndrome in a Thalassemic Patient

Thalassemia, a congenital hemoglobinopathy, is characterized by impaired erythropoiesis and peripheral hemolysis, leading to anemia. Thalassemia major, in particular, necessitates regular blood transfusions, resulting in iron accumulation in the body. Iron overload primarily affects the heart and can induce cardiac disorder, including defects in the pump and conduction system, which is one of the leading causes of mortality among thalassemics. The existing literature has revealed limited support for the occurrence of acute coronary syndrome (ACS) due to hemochromatosis. However, it does show that elevated troponin levels can be observed even in cases not associated with ACS. Here, we offer a rare case study of acute coronary syndrome in a patient with thalassemia major who also had elevated ferritin levels and abnormal troponin I values. The difficulty of cardiac problems in thalassemia major is highlighted by this case, as well as the necessity for more clinical attention and study to better comprehend and handle such instances.

T2* map at cardiac MRI reveals incidental hepatic and cardiac iron overload

PURPOSE

The purpose of this study was to assess the diagnostic capabilities of cardiac magnetic resonance (CMR) T2* mapping in detecting incidental hepatic and cardiac iron overload.

MATERIALS AND METHODS

Patients with various clinical indications for CMR examination were consecutively included at a single center from January 2019 to April 2023. All patients underwent T2* mapping at 1.5 T in a single mid-ventricular short-axis as part of a comprehensive routine CMR protocol. T2* measurements were performed of the heart (using a region-of-interest in the interventricular septum) and the liver, categorized according to the severity of iron overload. The degree of cardiac iron overload was categorized as mild (15 ms < T2* < 20 ms), moderate (10 ms < T2* < 15 ms) and severe (T2* < 10 ms). The degree of hepatic iron overload was categorized as mild (4 ms < T2* < 8 ms), moderate (2 ms < T2* < 4 ms), severe (T2* < 2 ms). Image quality and inter-reader agreement were assessed using intraclass correlation coefficient (ICC).

RESULTS

CMR examinations from 614 patients (374 men, 240 women) with a mean age of 50 ± 18 (standard deviation) years were fully evaluable. A total of 24/614 patients (3.9%) demonstrated incidental hepatic iron overload; of these, 22/614 patients (3.6%) had mild hepatic iron overload, and 2/614 patients (0.3%) had moderate hepatic iron overload. Seven out of 614 patients (1.1%) had incidental cardiac iron overload; of these, 5/614 patients (0.8%) had mild iron overload, 1/614 patients (0.2%) had moderate iron overload, and 1/614 patients (0.2%) had severe iron overload. Good to excellent inter-reader agreement was observed for the assessment of T2* values (ICC, 0.90 for heart [95% confidence interval: 0.88-0.91]; ICC, 0.91 for liver [95% confidence interval: 0.89-0.92]).

CONCLUSION

Analysis of standard CMR T2* maps detects incidental cardiac and hepatic iron overload in 1.1% and 3.9% of patients, respectively, which may have implications for further patient management. Therefore, despite an overall low number of incidental abnormal findings, T2* imaging may be included in a standardized comprehensive CMR protocol.

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.

Successful chelation in beta-thalassemia major in the 21st century

This century has seen a revolution the management of beta-thalassemia major. Over a 12-year period to 2016, we aimed to analyze the benefits of such advances. In 209 patients, independent of the chelation regimen, ferritin, cardiac T2* and liver iron concentration changes were evaluated. We defined chelation success (ChS) as no iron load in the heart and acceptable levels in the liver. Over 3 early magnetic resonance imagings, the same parameters were assessed in 2 subgroups, the only 2 that had sufficient patients continuing on 1 regimen and for a significant period of time, 1 on deferrioxamine (low iron load patients n = 41, Group A) and 1 on deferoxamine-deferiprone (iron overloaded n = 60, Group B). Finally, 28 deaths and causes were compared to those of an earlier period. The 209 patients significantly optimized those indices, while the number of patients with chelation success, increased from 6% to 51% (P < .0001). In group A, ChS after about 8 years increased from 21 to 46% (P = .006), while in Group B, from 0% to 60% (P < .001) after about 7 years. Deaths over the 2 periods showed significant reduction. Combined clearance of cardiac and liver iron (ChS) is feasible and should become the new target for all patients. This requires, serial magnetic resonance imagings and often prolonged intensified chelation for patients.

Phenotyping heart failure by cardiac magnetic resonance imaging of cardiac macro- and microscopic structure: state of the art review

Heart failure demographics have evolved in past decades with the development of improved diagnostics, therapies, and prevention. Cardiac magnetic resonance (CMR) has developed in a similar timeframe to become the gold-standard non-invasive imaging modality for characterizing diseases causing heart failure. CMR techniques to assess cardiac morphology and function have progressed since their first use in the 1980s. Increasingly efficient acquisition protocols generate high spatial and temporal resolution images in less time. This has enabled new methods of characterizing cardiac systolic and diastolic function such as strain analysis, exercise real-time cine imaging and four-dimensional flow. A key strength of CMR is its ability to non-invasively interrogate the myocardial tissue composition. Gadolinium contrast agents revolutionized non-invasive cardiac imaging with the late gadolinium enhancement technique. Further advances enabled quantitative parametric mapping to increase sensitivity at detecting diffuse pathology. Novel methods such as diffusion tensor imaging and artificial intelligence-enhanced image generation are on the horizon. Magnetic resonance spectroscopy (MRS) provides a window into the molecular environment of the myocardium. Phosphorus (31P) spectroscopy can inform the status of cardiac energetics in health and disease. Proton (1H) spectroscopy complements this by measuring creatine and intramyocardial lipids. Hyperpolarized carbon (13C) spectroscopy is a novel method that could further our understanding of dynamic cardiac metabolism. CMR of other organs such as the lungs may add further depth into phenotypes of heart failure. The vast capabilities of CMR should be deployed and interpreted in context of current heart failure challenges.

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.

Correlation of Transient Elastography with Liver Iron Concentration and Serum Ferritin Levels in Patients with Transfusion-Dependent Thalassemia Major from Oman

Aims

In a longitudinal study, we aimed to assess the correlation between ultrasound transient elastography (TE), serum ferritin (SF), liver iron content (LIC) by magnetic resonance imaging (MRI) T2* along with the fibrosis-4 (FIB-4) score as a screening tool to detect significant liver fibrosis among chronically transfusion-dependent beta-thalassemia (TDT) patients.

Methods

The study was conducted at a tertiary health center treating TDT patients. Transient elastography was performed within 3 months of Liver MRI T2* examinations at the radiology department over a median of one-year duration. T-test for independent data or Mann-Whitney U test was used to analyze group differences. Spearman correlation with linear regression analysis was used to evaluate the correlation between TE liver stiffness measurements, Liver MRI T2* values, and SF levels.

Results

In this study on 91 patients, the median age (IQR) of the subjects was 33 (9) years, and the median (IQR) body mass index was 23.8 (6.1) kg/m2. Median (IQR) TE by fibroscan, MRI T2*(3T), Liver iron concentration (LIC) by MRI Liver T2*, and SF levels were 6.38 (2.6) kPa, 32.4 (18) milliseconds, 7(9) g/dry wt., and 1881 (2969) ng/mL, respectively. TE measurements correlated with LIC g/dry wt. (rS =0.39, p=0.0001) and with SF level (rS =0.43, P=0.001) but not with MRI T2* values (rS =-0.24; P=0.98).

Conclusion

In TDT patients, liver stiffness measured as TE decreased significantly with improved iron overload measured as LIC by MRI and SF levels. However, there was no correlation of TE with the fibrosis-4 (FIB-4) score.

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.

Iron Load Toxicity in Medicine: From Molecular and Cellular Aspects to Clinical Implications

Iron is essential for all organisms and cells. Diseases of iron imbalance affect billions of patients, including those with iron overload and other forms of iron toxicity. Excess iron load is an adverse prognostic factor for all diseases and can cause serious organ damage and fatalities following chronic red blood cell transfusions in patients of many conditions, including hemoglobinopathies, myelodyspasia, and hematopoietic stem cell transplantation. Similar toxicity of excess body iron load but at a slower rate of disease progression is found in idiopathic haemochromatosis patients. Excess iron deposition in different regions of the brain with suspected toxicity has been identified by MRI T2* and similar methods in many neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease. Based on its role as the major biological catalyst of free radical reactions and the Fenton reaction, iron has also been implicated in all diseases associated with free radical pathology and tissue damage. Furthermore, the recent discovery of ferroptosis, which is a cell death program based on free radical generation by iron and cell membrane lipid oxidation, sparked thousands of investigations and the association of iron with cardiac, kidney, liver, and many other diseases, including cancer and infections. The toxicity implications of iron in a labile, non-protein bound form and its complexes with dietary molecules such as vitamin C and drugs such as doxorubicin and other xenobiotic molecules in relation to carcinogenesis and other forms of toxicity are also discussed. In each case and form of iron toxicity, the mechanistic insights, diagnostic criteria, and molecular interactions are essential for the design of new and effective therapeutic interventions and of future targeted therapeutic strategies. In particular, this approach has been successful for the treatment of most iron loading conditions and especially for the transition of thalassemia from a fatal to a chronic disease due to new therapeutic protocols resulting in the complete elimination of iron overload and of iron toxicity.

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.

The Vital Role Played by Deferiprone in the Transition of Thalassaemia from a Fatal to a Chronic Disease and Challenges in Its Repurposing for Use in Non-Iron-Loaded Diseases

The iron chelating orphan drug deferiprone (L1), discovered over 40 years ago, has been used daily by patients across the world at high doses (75-100 mg/kg) for more than 30 years with no serious toxicity. The level of safety and the simple, inexpensive synthesis are some of the many unique properties of L1, which played a major role in the contribution of the drug in the transition of thalassaemia from a fatal to a chronic disease. Other unique and valuable clinical properties of L1 in relation to pharmacology and metabolism include: oral effectiveness, which improved compliance compared to the prototype therapy with subcutaneous deferoxamine; highly effective iron removal from all iron-loaded organs, particularly the heart, which is the major target organ of iron toxicity and the cause of mortality in thalassaemic patients; an ability to achieve negative iron balance, completely remove all excess iron, and maintain normal iron stores in thalassaemic patients; rapid absorption from the stomach and rapid clearance from the body, allowing a greater frequency of repeated administration and overall increased efficacy of iron excretion, which is dependent on the dose used and also the concentration achieved at the site of drug action; and its ability to cross the blood-brain barrier and treat malignant, neurological, and microbial diseases affecting the brain. Some differential pharmacological activity by L1 among patients has been generally shown in relation to the absorption, distribution, metabolism, elimination, and toxicity (ADMET) of the drug. Unique properties exhibited by L1 in comparison to other drugs include specific protein interactions and antioxidant effects, such as iron removal from transferrin and lactoferrin; inhibition of iron and copper catalytic production of free radicals, ferroptosis, and cuproptosis; and inhibition of iron-containing proteins associated with different pathological conditions. The unique properties of L1 have attracted the interest of many investigators for drug repurposing and use in many pathological conditions, including cancer, neurodegenerative conditions, microbial conditions, renal conditions, free radical pathology, metal intoxication in relation to Fe, Cu, Al, Zn, Ga, In, U, and Pu, and other diseases. Similarly, the properties of L1 increase the prospects of its wider use in optimizing therapeutic efforts in many other fields of medicine, including synergies with other drugs.

Imaging in Heart Failure with Preserved Ejection Fraction: A Multimodality Imaging Point of View

Heart failure with preserved ejection fraction (HFpEF) is an important global health problem. Despite increased prevalence due to improved diagnostic options, limited improvement has been achieved in cardiac outcomes. HFpEF is an extremely complex syndrome and multimodality imaging is important for diagnosis, identifying its different phenotypes and determining prognosis. Evaluation of left ventricular filling pressures using echocardiographic diastolic function parameters is the first step of imaging in clinical practice. The role of echocardiography is becoming more popular and with the recent developments in deformation imaging, cardiac MRI is extremely important as it can provide tissue characterisation, identify fibrosis and optimal volume measurements of cardiac chambers. Nuclear imaging methods can also be used in the diagnosis of specific diseases, such as cardiac amyloidosis.

Long-term Results of Splenectomy in Transfusion-dependent Thalassemia

Splenectomy is indicated in transfusion-dependent thalassemia (TDT) only in certain situations. This study aimed to present the effectiveness, complications, and long-term follow-up results of splenectomy in children with TDT. We performed a 30-year single-institution analysis of cases of splenectomy for TDT between 1987 and 2017 and their follow-up until 2021. A total of 39 children (female/male: 24/15) were included. The mean age at splenectomy was 11.2±3.2 years, and their mean follow-up duration after splenectomy was 21.5±6.4 years. Response was defined according to the patient's annual transfusion requirement in the first year postsplenectomy and on the last follow-up year. Complete response was not seen in any of the cases; partial response was observed in 32.3% and no response in 67.6%. Thrombocytosis was seen in 87% of the patients. The platelet counts of 7 (17.9%) patients were >1000 (10 9 /L), and aspirin prophylaxis was given to 22 (56.4%) patients. Complications were thrombosis in 2 (5.1%) patients, infections in 11 (28.2%) patients, and pulmonary hypertension in 4 (10.2%) patients. Our study showed that after splenectomy, the need for transfusion only partially decreased in a small number of TDT patients. We think splenectomy can be delayed with appropriate chelation therapy up to higher annual transfusion requirement values.

Quantification of Liver Iron Overload with MRI: Review and Guidelines from the ESGAR and SAR

Accumulation of excess iron in the body, or systemic iron overload, results from a variety of causes. The concentration of iron in the liver is linearly related to the total body iron stores and, for this reason, quantification of liver iron concentration (LIC) is widely regarded as the best surrogate to assess total body iron. Historically assessed using biopsy, there is a clear need for noninvasive quantitative imaging biomarkers of LIC. MRI is highly sensitive to the presence of tissue iron and has been increasingly adopted as a noninvasive alternative to biopsy for detection, severity grading, and treatment monitoring in patients with known or suspected iron overload. Multiple MRI strategies have been developed in the past 2 decades, based on both gradient-echo and spin-echo imaging, including signal intensity ratio and relaxometry strategies. However, there is a general lack of consensus regarding the appropriate use of these methods. The overall goal of this article is to summarize the current state of the art in the clinical use of MRI to quantify liver iron content and to assess the overall level of evidence of these various methods. Based on this summary, expert consensus panel recommendations on best practices for MRI-based quantification of liver iron are provided.

Deep Learning-Based Reconstruction for Cardiac MRI: A Review

Cardiac magnetic resonance (CMR) is an essential clinical tool for the assessment of cardiovascular disease. Deep learning (DL) has recently revolutionized the field through image reconstruction techniques that allow unprecedented data undersampling rates. These fast acquisitions have the potential to considerably impact the diagnosis and treatment of cardiovascular disease. Herein, we provide a comprehensive review of DL-based reconstruction methods for CMR. We place special emphasis on state-of-the-art unrolled networks, which are heavily based on a conventional image reconstruction framework. We review the main DL-based methods and connect them to the relevant conventional reconstruction theory. Next, we review several methods developed to tackle specific challenges that arise from the characteristics of CMR data. Then, we focus on DL-based methods developed for specific CMR applications, including flow imaging, late gadolinium enhancement, and quantitative tissue characterization. Finally, we discuss the pitfalls and future outlook of DL-based reconstructions in CMR, focusing on the robustness, interpretability, clinical deployment, and potential for new methods.

Pulmonary function in patients with transfusion-dependent thalassemia and its associations with iron overload

In patients with transfusion-dependent thalassemia (TDT), pulmonary function impairment has been reported but data are conflicting. Moreover, it remains unclear whether pulmonary dysfunction is associated with iron overload. This study aimed to evaluate the pulmonary function in patients with TDT and to investigate the associations between pulmonary dysfunction and iron overload. It was a retrospective observational study. 101 patients with TDT were recruited for lung function tests. The most recent ferritin levels (pmol/L) and the magnetic resonance imaging (MRI) measurements of the myocardial and liver iron status, as measured by heart and liver T2* relaxation time (millisecond, ms) respectively, were retrieved from the computerized medical records. Only data within 12 months from the lung function measurement were included in the analysis. The serum ferritin, and the cardiac and liver T2* relaxation time were the surrogate indexes of body iron content. The threshold of abnormality in lung function was defined as under 80% of the predicted value. 101 subjects were recruited with a mean age of 25.1 years (standard deviation (SD) 7.9 years). Thirty-eight (38%) and five (5%) demonstrated restrictive and obstructive lung function deficits, respectively. A weak correlation of FVC %Predicted and TLC %Predicted with MRI myocardial T2* relaxation time (rho = 0.32, p = 0.03 and rho = 0.33, p = 0.03 respectively) was observed. By logistic regression, MRI cardiac T2* relaxation time was negatively associated with restrictive lung function deficit (B - 0.06; SE 0.03; Odds ratio 0.94; 95% confidence interval (CI) 0.89-0.99; p = 0.023) after adjusting for age, sex and body mass index. Restrictive pulmonary function deficit was commonly observed in patients with TDT, and the severity potentially correlates with myocardial iron content. Monitoring of lung function in this group of patients, particularly for those with iron overload, is important.

Optimized serum ferritin prediction of iron overload in transfusion-dependent thalassemia: likelihood ratio and age-adjustment approach

BACKGROUND

Early detection of iron overload in transfusion-dependent thalassemia (TDT) patients is critical to prevent complications and improve survival.

OBJECTIVES

Evaluate the utility of serum ferritin (SF) in the prediction of hepatic and myocardial iron overload (HIO and MIO) compared to T2*-MRI.

DESIGN

Retrospective SETTINGS: Governmental hospitals.

PATIENTS AND METHODS

Patients with TDT who had T2*-MRI examinations between January 2016 to October 2019 were included. The predictive value of SF for detection of HIO and MIO was assessed by measuring area under the curve (AUC). A sample size of 123 cases was calculated to detect a correlation of 0.25 with 90% power and a two-sided type I error of 0.05.

MAIN OUTCOME MEASURES

The correlation between SF and estimated hepatic iron concentration.

SAMPLE SIZE

137 TDT patients who required regular blood transfusions.

RESULTS

The predictive value of SF was excellent for detection of HIO (AUC=0.83-0.87) but fair for detection of MIO (AUC=0.67). The two independent predictors of MIO were age and SF. The log of (age × SF) enhanced the SF predictive value for MIO (AUC=0.78). SF values of 700 and 1250 mg/L effectively excluded mild and moderate HIO with a sensitivity of 97.8% and 94.2%, respectively (LR-=0.1). While SF values of 1640 and 2150 mg/L accurately diagnosed mild and moderate HIO with a specificity of 95.55% and 96.4%, respectively (LR+>10). A log of (age × SF) cut-off value of 4.15 effectively excluded MIO (LR-=0.1), while a value of 4.65 moderately confirmed MIO (LR+=3.2).

CONCLUSIONS

SF is an excellent predictor of hepatic IO in TDT. Age adjustment enhanced its myocardial IO predictive accuracy. Likelihood ratio-based SF cut-off values may help clinicians in risk stratification and treatment decision-making.

LIMITATIONS

The laboratory data were gathered retrospectively and although the risk of selection bias for T2*-MRI examination is thought to be low, it cannot be ignored.

CONFLICT OF INTEREST

None.

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.

Thalassaemia-A global view

The thalassaemias are a group of genetic disorders of haemoglobin which are endemic in the tropics but are now found worldwide due to migration. Basic standard of care therapy includes regular transfusions to maintain a haemoglobin level of around 10 g/dL, together with iron chelation therapy to prevent iron overload. Novel therapies, bone marrow transplantation, and gene therapy are treatment options that are unavailable in many countries with stressed economies. This Wider Perspectives article presents the strategies for management of an adolescent refugee patient with beta thalassaemia, as it would be performed by expert haematologists in six countries: Italy, Lebanon, Oman, the Sudan, Thailand and the United States. The experienced clinicians in each country have adapted their practice according to the resources available, which vary greatly. Even in the current modern era, providing adequate transfusions and chelation is problematic in many countries. On the other hand, ensuring adherence to therapy, particularly during adolescence, is a similar challenge seen in all countries. The concluding section highlights the disparities in available therapies and puts the role of novel therapies into a societal context.

mDIXON-Quant technique diagnostic accuracy for assessing bone mineral density in male adult population

BACKGROUND

To investigate the diagnostic efficacy of mDIXON-Quant technique for prediction of bone loss in male adults.

METHODS

One hundred thirty-eight male adults were divided into normal, osteopenia, and osteoporosis groups based on DXA and QCT for the lumbar spine. Differences in mDIXON-Quant parameters [fat fraction (FF) and T2^* value] among three groups, as well as the correlation of mDIXON-Quant parameters and bone mineral density (BMD) were analyzed. The areas under the curves (AUCs) for mDIXON-Quant parameters for prediction of low bone mass were calculated.

RESULTS

According to DXA standard, FF and T2^* value were significantly increased in osteoporosis group compared with normal group (P = 0.012 and P < 0.001). According to QCT standard, FF was significantly increased in osteopenia and osteoporosis groups compared with normal group (both P < 0.001). T2^* values were significantly different among three groups (all P < 0.05). After correction for age and body mass index, FF was negatively correlated with areal BMD and volumetric BMD (r = -0.205 and -0.604, respectively; both P < 0.05), and so was T2^* value (r = -0.324 and -0.444, respectively; both P < 0.05). The AUCs for predicting low bone mass according to DXA and QCT standards were 0.642 and 0.898 for FF, 0.648 and 0.740 for T2^* value, and 0.677 and 0.920 for both combined, respectively.

CONCLUSIONS

FF combined with T2^* value has a better diagnostic efficacy than FF or T2^* value alone in prediction of low bone mass in male adults, which is expected to be a promising MRI method for the screening of bone quality.

TRIAL REGISTRATION

ChiCTR1900024511 (Registered 13-07-2019).

Vitamin D levels and left ventricular function in beta-thalassemia major with iron overload

Heart disease is the primary cause of death in patients with beta-thalassemia major. The study aimed to determine the association between vitamin D and left ventricular function in patients with beta-thalassemia major with iron overload. A cross-sectional hospital-based study was conducted, where the vitamin D and ferritin levels of children living with beta-thalassemia major were measured, and left ventricular function was assessed utilizing ejection fraction (EF) and fractional shortening (FS) using 2D echocardiography. The mean serum ferritin was 4622 ± 2289 ng/ml, and the mean serum vitamin D levels were 22 ± 7.7 ng/ml. The mean values of EF were 62.30 ± 6.9%, and FS was 31.21 ± 4.8%. Statistically significant negative correlation (r = -0.447, p < 0.001) was found between vitamin D and serum ferritin values, and a significant positive association was found between vitamin D levels concerning EF and FS with a p-value of 0.034 and 0.014, respectively.Conclusion: It was observed  that increasing ferritin was associated with lower vitamin D levels which in turn influenced fractional shortening /cardiac function in these patients.  What is Known: • Patients with Beta Thalassemia major on long term transfusion are prone to develop heart disease / cardiac failure due to chronic iron overload. What is New: • Patients with beta thalassemia major on long term term transfusions with iron overload who are vitamin D deficient are more prone to the cardiac complications which inturn can be prevented by vitamin D supplementation.

HIF2α activation and mitochondrial deficit due to iron chelation cause retinal atrophy

Iron accumulation causes cell death and disrupts tissue functions, which necessitates chelation therapy to reduce iron overload. However, clinical utilization of deferoxamine (DFO), an iron chelator, has been documented to give rise to systemic adverse effects, including ocular toxicity. This study provided the pathogenic and molecular basis for DFO-related retinopathy and identified retinal pigment epithelium (RPE) as the target tissue in DFO-related retinopathy. Our modeling demonstrated the susceptibility of RPE to DFO compared with the neuroretina. Intriguingly, we established upregulation of hypoxia inducible factor (HIF) 2α and mitochondrial deficit as the most prominent pathogenesis underlying the RPE atrophy. Moreover, suppressing hyperactivity of HIF2α and preserving mitochondrial dysfunction by α-ketoglutarate (AKG) protects the RPE against lesions both in vitro and in vivo. This supported our observation that AKG supplementation alleviates visual impairment in a patient undergoing DFO-chelation therapy. Overall, our study established a significant role of iron deficiency in initiating DFO-related RPE atrophy. Inhibiting HIF2α and rescuing mitochondrial function by AKG protect RPE cells and can potentially ameliorate patients' visual function.

Serum Ferritin Levels and Other Associated Parameters with Diabetes Mellitus in Adult Patients Suffering from Beta Thalassemia Major

Background

Although beta thalassemia major (BTM) patients are properly treated with blood transfusions in accompany with iron chelation therapy, they suffer from complications, such as diabetes mellitus (DM).

Purpose

The purpose was to detect the critical serum ferritin level and other parameters correlated with DM among adult BTM patients. Also, it was to study whether each of these parameters is associated with a certain period of age.

Patients and Methods

This study included 200 adult BTM patients. A cross-sectional study was carried out. Patients clinical and laboratory variables, such as ferritin levels, and fasting blood glucose (FBS) were extracted from medical records at Zagazig University Hospital, Egypt. Liver and cardiac iron contents were assessed using MRI T2* methods. Statistical analysis was performed using IBM SPSS V26.0 software package.

Results

The overall frequency of DM over the total sample equals 6.5%. There were no impaired fasting glucose (IFG) in the medical records. Statistical significance between serum ferritin and DM was (P = 0.014). The serum ferritin 2500 ng/mL with age group (27-<32) years-old were risk factors. The distributions of DM according to BMI were (3.5%) of class overweight. Significant association between DM and BMI was (r = 0.357, P < 0.001). Liver MRI T2* has significant correlation with serum ferritin, but cardiac MRI T2* was poorly correlated. Association between liver and cardiac MRI T2* was not found.

Conclusion

Age group (27-<32) years-old and ferritin >2500 ng/mL should be properly treated immediately. The serum ferritin and BMI of class "overweight" were risk factors for DM. Factors such as diet should be followed. Serum ferritin can be used for estimating liver iron content for economic factors. But cardiac MRI T2* must be performed for evaluating cardiac iron accurately.

Prognostic value of multiparametric cardiac magnetic resonance in sickle cell patients

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

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.

Monitoring kidney size to interpret MRI-based assessment of renal oxygenation in acute pathophysiological scenarios

AIM

Tissue hypoxia is an early key feature of acute kidney injury. Assessment of renal oxygenation using magnetic resonance imaging (MRI) markers T₂ and T₂ * enables insights into renal pathophysiology. This assessment can be confounded by changes in the blood and tubular volume fractions, occurring upon pathological insults. These changes are mirrored by changes in kidney size (KS). Here, we used dynamic MRI to monitor KS for physiological interpretation of T₂ * and T₂ changes in acute pathophysiological scenarios.

METHODS

KS was determined from T₂ *, T₂ mapping in rats. Six interventions that acutely alter renal tissue oxygenation were performed directly within the scanner, including interventions that change the blood and/or tubular volume. A biophysical model was used to estimate changes in O₂ saturation of hemoglobin from changes in T₂ * and KS.

RESULTS

Upon aortic occlusion KS decreased; this correlated with a decrease in T₂ *, T₂ . Upon renal vein occlusion KS increased; this negatively correlated with a decrease in T₂ *, T₂ . Upon simultaneous occlusion of both vessels KS remained unchanged; there was no correlation with decreased T₂ *, T₂ . Hypoxemia induced mild reductions in KS and T₂ *, T₂ . Administration of an X-ray contrast medium induced sustained KS increase, with an initial increase in T₂ *, T₂ followed by a decrease. Furosemide caused T₂ *, T₂ elevation and a minor increase in KS. Model calculations yielded physiologically plausible calibration ratios for T₂ *.

CONCLUSION

Monitoring KS allows physiological interpretation of acute renal oxygenation changes obtained by T₂ *, T₂ . KS monitoring should accompany MRI-oximetry, for new insights into renal pathophysiology and swift translation into human studies.

Multicenter Reproducibility of Liver Iron Quantification with 1.5-T and 3.0-T MRI

Background MRI is a standard of care tool to measure liver iron concentration (LIC). Compared with regulatory-approved R2 MRI, R2* MRI has superior speed and is available in most MRI scanners; however, the cross-vendor reproducibility of R2*-based LIC estimation remains unknown. Purpose To evaluate the reproducibility of LIC via single-breath-hold R2* MRI at both 1.5 T and 3.0 T with use of a multicenter, multivendor study. Materials and Methods Four academic medical centers using MRI scanners from three different vendors (three 1.5-T scanners, one 2.89-T scanner, and two 3.0-T scanners) participated in this prospective cross-sectional study. Participants with known or suspected liver iron overload were recruited to undergo multiecho gradient-echo MRI for R2* mapping at 1.5 T and 3.0 T (2.89 T or 3.0 T) on the same day. R2* maps were reconstructed from the multiecho images and analyzed at a single center. Reference LIC measurements were obtained with a commercial R2 MRI method performed using standardized 1.5-T spin-echo imaging. R2*-versus-LIC calibrations were generated across centers and field strengths using linear regression and compared using F tests. Receiver operating characteristic (ROC) curve analysis was used to determine the diagnostic performance of R2* MRI in the detection of clinically relevant LIC thresholds. Results A total of 207 participants (mean age, 38 years ± 20 [SD]; 117 male participants) were evaluated between March 2015 and September 2019. A linear relationship was confirmed between R2* and LIC. All calibrations within the same field strength were highly reproducible, showing no evidence of statistically significant center-specific differences (P > .43 across all comparisons). Calibrations for 1.5 T and 3.0 T were generated, as follows: for 1.5 T, LIC (in milligrams per gram [dry weight]) = -0.16 + 2.603 × 10-2 R2* (in seconds-1); for 2.89 T, LIC (in milligrams per gram) = -0.03 + 1.400 × 10-2 R2* (in seconds-1); for 3.0 T, LIC (in milligrams per gram) = -0.03 + 1.349 × 10-2 R2* (in seconds-1). Liver R2* had high diagnostic performance in the detection of clinically relevant LIC thresholds (area under the ROC curve, >0.98). Conclusion R2* MRI enabled accurate and reproducible quantification of liver iron overload over clinically relevant ranges of liver iron concentration (LIC). The data generated in this study provide the necessary calibrations for broad clinical dissemination of R2*-based LIC quantification. ClinicalTrials.gov registration no.: NCT02025543 © RSNA, 2022 Online supplemental material is available for this article.

Cardiac Magnetic Resonance Strain in Beta Thalassemia Major Correlates with Cardiac Iron Overload

BACKGROUND

Beta thalassemia major (Beta-TM) is an inherited condition which presents at around two years of life. Patients with Beta-;TM may develop cardiac iron toxicity secondary to transfusion dependence. Cardiovascular magnetic resonance (CMR) T2*, a technique designed to quantify myocardial iron deposition, is a driving component of disease management. A decreased T2* value represents increasing cardiac iron overload. The clinical manifestation is a decline in ejection fraction (EF). However, there may be early subclinical changes in cardiac function that are not detected by changes in EF. CMR-derived strain assesses myocardial dysfunction prior to decline in EF. Our primary aim was to assess the correlation between CMR strain and T2* in the Beta-TM population.

METHODS

Circumferential and longitudinal strain was analyzed. Pearson's correlation was calculated for T2* values and strain in the Beta-TM population.

RESULTS

We identified 49 patients and 18 controls. Patients with severe disease (low T2*) were found to have decreased global circumferential strain (GCS) in comparison to other T2* groups. A correlation was identified between GCS and T2* (r = 0.5; p < 0.01).

CONCLUSION

CMR-derived strain can be a clinically useful tool to predict early myocardial dysfunction in Beta-TM.

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

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

Cardiovascular magnetic resonance for the evaluation of patients with cardiovascular disease: An overview of current indications, limitations, and procedures

Cardiovascular disease (CVD) is the most common cause of morbidity/mortality worldwide. Early diagnosis is the key to improve CVD prognosis, and cardiovascular imaging plays a crucial role in this direction. Echocardiography is the most commonly used imaging modality. However, the need for early diagnosis/treatment favors the development of modalities providing information about tissue characterization beyond echocardiography. In this context, the rapid evolution of cardiovascular magnetic resonance (CMR) led to the coexistence of cardiologists and radiologists in the CMR field. Our aim was to provide an overview of indications, sequences, and reporting of CMR findings in various CVDs. The indications/limitations of CMR as well as the pathophysiological significance of various sequences in adult/pediatric CVDs are presented and discussed in detail. The role of CMR indices in the evaluation of the most common clinical scenarios in cardiology and their impact on CVD diagnosis/prognosis were analyzed in detail. Additionally, the comparison of CMR versus other imaging modalities is also discussed. Finally, future research directions are presented. CMR can provide cardiac tissue characterization and biventricular/biatrial functional assessment in the same examination, allowing for early and accurate identification of important subclinical abnormalities, before clinically overt CVD takes place.

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.

Clinical application of CMR in cardiomyopathies: evolving concepts and techniques : A position paper of myocardial and pericardial diseases and cardiac magnetic resonance working groups of Italian society of cardiology

Cardiac magnetic resonance (CMR) has become an essential tool for the evaluation of patients affected or at risk of developing cardiomyopathies (CMPs). In fact, CMR not only provides precise data on cardiac volumes, wall thickness, mass and systolic function but it also a non-invasive characterization of myocardial tissue, thus helping the early diagnosis and the precise phenotyping of the different CMPs, which is essential for early and individualized treatment of patients. Furthermore, several CMR characteristics, such as the presence of extensive LGE or abnormal mapping values, are emerging as prognostic markers, therefore helping to define patients' risk. Lastly new experimental CMR techniques are under investigation and might contribute to widen our knowledge in the field of CMPs. In this perspective, CMR appears an essential tool to be systematically applied in the diagnostic and prognostic work-up of CMPs in clinical practice. This review provides a deep overview of clinical applicability of standard and emerging CMR techniques in the management of CMPs.