Risk factors for heart disease in transfusion-dependent thalassemia: serum ferritin revisited

Quantitative MRI evaluation of iron deposition in patients with transfusion-dependent thalassemia: clinical management insights

BACKGROUND

In patients with thalassemia, different organs are affected differently by iron overload. Nevertheless, the reasons for this could be the same key transporters. This study investigated the iron deposition in different organs of transfusion-dependent thalassemia (TDT) patients and its correlation.

RESEARCH DESIGN AND METHODS

This cross-sectional study involved 54 TDT patients who underwent MRI T2* examinations of the heart, liver, pancreas, spleen, kidneys, and pituitary. The study analyzed the iron deposition in each organ and evaluated the correlation of iron deposition using Spearman's test.

RESULTS

Among the 54 patients with TDT, liver iron overload was found in 49/54 (90.7%) cases, pancreas iron overload in 43/54 (79.6%) cases, spleen iron overload in 18/26 (69.2%) patients, heart iron overload in 20/54 (37.0%) cases, and kidney iron overload in 8/54 (14.8%) patients. Most patients (66.7%) with iron overload in the liver but not in the heart exhibited spleen iron abnormalities. Pituitary T2* and pancreas T2* (r = 0.790), pituitary T2* and kidney T2* (r = 0.692), kidney T2* and pancreas T2* (r = 0.672) showed positive correlation (all p < 0.05).

CONCLUSIONS

Patients with TDT exhibited significant organ-specific iron overload. These findings highlight the importance of routine MRI screening for monitoring and managing iron overload in patients with TDT. Pituitary, pancreas, and kidney may have similar iron-loading mechanisms.

Application of the magnetic resonance 3D multiecho Dixon sequence for quantifying hepatic iron overload and steatosis in patients with thalassemia

OBJECTIVE

To investigate the feasibility and diagnostic efficacy of a 3D multiecho Dixon (qDixon) research application for simultaneously quantifying the liver iron concentration (LIC) and steatosis in thalassemia patients.

MATERIALS AND METHODS

This prospective study enrolled participants with thalassemia who underwent 3 T MRI of the liver for the evaluation of hepatic iron overload. The imaging protocol including qDixon and conventional T2* mapping based on 2D multiecho gradient echo (ME GRE) sequences respectively. Regions of interest (ROIs) were drawn in the liver on the qDixon maps to obtain R2* and proton density fat fraction (PDFF). The reference R2* value was measured and calculated on conventional T2* mapping using the CMRtools software. Correlation analysis, Linear regression analysis, and Bland-Altman analysis were performed.

RESULTS

84 patients were finally included in this study. The median R2*-ME-GRE was 366.97 (1/s), range [206.68 (1/s), 522.20 (1/s)]. 8 patients had normal hepatic iron deposition, 16 had Insignificant, 42 had mild, 18 had moderate. The median of R2*-qDixon was 376.88 (1/s) [219.33 (1/s), 491.75 (1/s)]. A strong correlation was found between the liver R2*-qDixon and the R2*-ME-GRE (r = 0.959, P < 0.001). The median value of PDFF was 1.76% (1.10%, 2.95%). 8 patients had mild fatty liver, and 1 had severe fatty liver.

CONCLUSION

MR qDixon research sequence can rapidly and accurately quantify liver iron overload, that highly consistent with the measured via conventional GRE sequence, and it can also simultaneously detect hepatic steatosis, this has great potential for clinical evaluation of thalassemia patients.

COVID-19 and β-thalassemia: in lieu of evidence and vague nexus

Coronavirus disease 19 (COVID-19) is an infectious disease caused by severe acute respiratory coronavirus 2 (SARS-CoV-2) causing acute systemic disorders and multi-organ damage. β-thalassemia (β-T) is an autosomal recessive disorder leading to the development of anemia. β-T may lead to complications such as immunological disorders, iron overload, oxidative stress, and endocrinopathy. β-T and associated complications may increase the risk of SARS-CoV-2, as inflammatory disturbances and oxidative stress disorders are linked with COVID-19. Therefore, the objective of the present review was to elucidate the potential link between β-T and COVID-19 regarding the underlying comorbidities. The present review showed that most of the β-T patients with COVID-19 revealed mild to moderate clinical features, and β-T may not be linked with Covid-19 severity. Though patients with transfusion-dependent β-T (TDT) develop less COVID-19 severity compared to non-transfusion-depend β-T(NTDT), preclinical and clinical studies are recommended in this regard.

Prediction of Heart and Liver Iron Overload in β-Thalassemia Major Patients Using Machine Learning Methods

Patients with β-thalassemia major (β-TM) face a wide range of complications as a result of excess iron in vital organs, including the heart and liver. Our aim was to find the best predictive machine learning (ML) model for assessing heart and liver iron overload in patients with β-TM. Data from 624 β-TM patients were entered into three ML models using random forest (RF), gradient boost model (GBM), and logistic regression (LR). The data were classified and analyzed by R software. Four evaluation metrics of predictive performance were measured: sensitivity, specificity, accuracy, and area under the curve (AUC), operating characteristic curve. For heart iron overload, the LR had the highest predictive performance based on AUC: 0.68 [95% CI (95% confidence interval): 0.60, 0.75]. The GBM also had the highest specificity (69.0%) and accuracy (67.0%). Most sensitivity is also acquired with LR (75.0%). For liver iron overload, the highest performance based on AUC was observed with RF, AUC: 0.68 (95% CI: 0.59, 0.76). The RF showed the highest accuracy (66.0%) and specificity (66.0%), while the LR had the highest sensitivity (84.0%). Ferritin, duration of transfusion, and age were determined as the most effective predictors of iron overload in both heart and liver. Logistic regression LR was determined to be the strongest method to predict cardiac and RF values for liver iron overload in patients with β-TM. Older thalassemia patients with a high serum ferritin (SF) level and a longer duration of transfusion therapy were more prone to heart and liver iron overload.

Prediction of long-term survival in patients with transfusion-dependent hemoglobinopathies: Insights from cardiac imaging and ferritin

AIMS

The current study evaluated the association of echocardiography, cardiac magnetic resonance (CMR), and ferritin data with 10-year survival in thalassemia patients.

METHODS

Demographics, ferritin, echocardiography, and CMR parameters of stable consecutive thalassemia patients were prospectively collected.

RESULTS

In total, 75 patients (mean age 37 ± 11 years, 45% male) with thalassemia were included and dichotomized based on their survival status after a median follow-up period of 10.3 [9.6-10.9] years. Older age (HR: 1.071, p = 0.001), ferritin ≥2000 ng/ml (HR: 4.682, p = 0.007) and ≥1700 ng/ml (HR: 7.817, p = 0.002), elevated LV end-diastolic pressure (HR: 1.019, p = 0.044), TR Vmax >2.8 m/s (HR: 6.845, p = 0.005), and CMR T2∗ ≤20 msec (HR: 3.602, p = 0.043) and ≤34 msec (HR: 5.854, p = 0.026) were associated with increased all-cause mortality (primary endpoint). A baseline model including age was created and became more predictive of worse survival by adding TR Vmax >2.8 m/s instead of elevated LV end-diastolic pressure (C index 0.767 vs. 0.760, respectively), ferritin ≥1700 ng/ml instead of ≥2000 ng/ml (C index 0.890 vs. 0.807, respectively), or CMR T2∗≤34 msec instead of ≤20 msec (C index 0.845 vs. 0.839, respectively). Parameters associated with the combined endpoint of cardiac mortality/cardiac hospitalization (secondary endpoint) after adjusting for age were ferritin ≥1700 ng/ml (HR 3.770, p = 0.014), ratio E/A wave >2 (HR 3.565, p = 0.04), TR Vmax >2.8 m/s (HR 4.541, p = 0.049), CMR T2∗ ≤20 ms (HR 9.462, p = 0.001), and CMR T2∗ ≤34 ms (HR 11.735, p = 0.002). The model including age and T2∗ ≤34 ms instead of T2∗ ≤20 ms was more predictive of the secondary endpoint (C-index 0.844 vs 0.838, respectively).

CONCLUSIONS

In thalassemia patients, TR Vmax >2.8 m/s, ferritin ≥2000 ng/ml, and CMR T2∗ ≤20 ms were associated with worse long-term survival. In the current era of advanced chelation therapy, aiming for ferritin ≤1700 ng/ml and CMR T2∗ ≥34 ms may improve their prognosis.

Management of Iron Overload in Beta-Thalassemia Patients: Clinical Practice Update Based on Case Series

Thalassemia syndromes are characterized by the inability to produce normal hemoglobin. Ineffective erythropoiesis and red cell transfusions are sources of excess iron that the human organism is unable to remove. Iron that is not saturated by transferrin is a toxic agent that, in transfusion-dependent patients, leads to death from iron-induced cardiomyopathy in the second decade of life. The availability of effective iron chelators, advances in the understanding of the mechanism of iron toxicity and overloading, and the availability of noninvasive methods to monitor iron loading and unloading in the liver, heart, and pancreas have all significantly increased the survival of patients with thalassemia. Prolonged exposure to iron toxicity is involved in the development of endocrinopathy, osteoporosis, cirrhosis, renal failure, and malignant transformation. Now that survival has been dramatically improved, the challenge of iron chelation therapy is to prevent complications. The time has come to consider that the primary goal of chelation therapy is to avoid 24-h exposure to toxic iron and maintain body iron levels within the normal range, avoiding possible chelation-related damage. It is very important to minimize irreversible organ damage to prevent malignant transformation before complications set in and make patients ineligible for current and future curative therapies. In this clinical case-based review, we highlight particular aspects of the management of iron overload in patients with beta-thalassemia syndromes, focusing on our own experience in treating such patients. We review the pathophysiology of iron overload and the different ways to assess, quantify, and monitor it. We also discuss chelation strategies that can be used with currently available chelators, balancing the need to keep non-transferrin-bound iron levels to a minimum (zero) 24 h a day, 7 days a week and the risk of over-chelation.

Changing patterns of thalassaemia in Italy: a WebThal perspective

BACKGROUND

Migration has impacted the spread of thalassaemia which is gradually becoming a global health problem. Italy, with an approximate estimation of 7,000 patients, does not have an accurate national record for haemoglobinopathies. This cross-sectional evaluation includes data for approximately 50% of beta-thalassaemia patients in Italy to provide an overview of the burden of thalassaemia syndromes.

MATERIALS AND METHODS

The analysis included data on epidemiology, transfusions and clinical parameters from 3,986 thalassaemia patients treated at 36 centres in Italy who were alive on 31^st December 2017. The study used WebThal, a computerised clinical record that is completely free-of-charge and that does not have any mandatory fields to be filled.

RESULTS

For patients with thalassaemia major, 68% were aged ≥35 years and 11% were aged ≤18 years. Patients with thalassaemia intermedia were slightly older. Transfusion data, reported in a subgroup of 1,162 patients, showed 9% had pre-transfusion haemoglobin <9 g/dL, 63% had levels between ≥9 and <10 g/dL, and 28% had levels ≥10 g/dL. These 1,162 patients underwent 22,272 transfusion days during 2017, with a mean of 19 transfusion days/year/patient (range 1-54 days). Severity of iron overload was reported in 756 patients; many had moderate or mild liver iron load (74% had liver iron <7.5 mg/g dry weight). In the same cohort, 85% of patients had no signs of cardiac iron load (MRT2* >20 ms), and only 3% showed signs of high-risk heart condition (T2* <10 ms). Most patients had normal alanine amino transferase levels due to treatment with the new anti-hepatitis C virus (HCV) drugs.

DISCUSSION

This study provides an overview of the current health status of patients with thalassaemia in Italy. Moreover, these data support the need for a national comprehensive thalassaemia registry.

The relationships between pancreatic T2* values and pancreatic iron loading with cardiac dysfunctions, hepatic and cardiac iron siderosis among Egyptian children and young adults with β-thalassaemia major and sickle cell disease: a cross-sectional study

Background: Cardiac, hepatic and pancreatic T2* measured by magnetic resonance imaging (MRI) has been proven to be an accurate and non-invasive method for measuring iron overload in iron overload conditions. There is accumulating evidence that pancreatic iron can predict cardiac iron in young children because the pancreas loads earlier than the heart. The aim of our study was to assess the relationships between pancreatic T2* values and pancreatic iron loading with cardiac dysfunctions and liver and cardiac iron among patients with β-thalassaemia major (βTM) and sickle cell disease (SCD).

Methods: 40 βTM and 20 transfusion-dependant SCD patients were included along with 60 healthy age and sex-matched controls. Echocardiography and Tissue Doppler Imaging were performed for all subjects as well as the control group.  Hepatic, cardiac and pancreatic iron overload in cases were assessed by MRI T2*.

Results:  The mean age of our patients was 13.7 years with mean frequency of transfusion/year 12. Mean cardiac T2* was 32.9 ms and mean myocardial iron concentration was 0.7 mg/g; One patient had cardiac iron overload of moderate severity. Mean pancreatic T2* was 22.3 ms with 20 patients having mild pancreatic iron overload.

Pancreatic T2* correlated positively peak late diastolic velocity at septal mitral annulus (r=0.269, p=0.038), peak early diastolic velocity at tricuspid annulus (r=0.430, p=0.001) and mitral annular plane systolic excursion (r=0.326, p=0.01); and negatively with end systolic pulmonary artery pressure (r=-0.343, p=0.007) and main pulmonary artery diameter (MPA) (r=-0.259, p=0.046). We couldn’t test the predictability of pancreatic T2* in relation to cardiac T2* as only one patient had cardiac T2*<20 ms.

Conclusion: There was a relationship between pancreatic iron siderosis with cardiac dysfunction in multi-transfused patients with βTM and SCD. No direct relation between pancreatic iron and cardiac siderosis was detected.

Prevalence and prognostic impact of left ventricular non-compaction in patients with thalassemia

A high incidence of isolated left ventricular non-compaction (LVNC) has been reported in previous studies on smaller cohorts of patients with thalassemia by cardiac MRI but the clinical impact of the finding is unknown. This prospective cohort study evaluates the prevalence and clinical implication of the finding. Prospective cohort study with enrollment of all consecutive cases with thalassemia referred for cardiac MRI from September 2007 to November 2014. The presence of LVNC was assessed according to the Petersen method and the Jacquier method, with the proposed changes by Fazio, Grothoff, and Chiodi. A clinical follow-up was performed in all patients. We included 560 patients with thalassemia (473 with thalassemia major and 87 with thalassemia intermedia: mean age 31.9 ± 10.6 years, male/female = 250/310). A total number of 1683 MRI tests were performed. A diagnosis of LVNC was determined according to adopted MR criteria in 44 patients (7.9%). Patients with LVNC had a significantly lower ejection fraction (52.68 ± 5.17% vs. 56.90 ± 6.34%; p = 0.0005) and greater indexed LV ESV (48.16 ± 10.03 ml/m² vs. 40.02 ± 10.06 ml/m²; p = 0.0022). After a mean follow-up time was 5.1 years, no significant change of MR parameters was detected as well as no clinical adverse events. LVNC is relatively frequent in patients with thalassemia. However, it is not associated with a worsening of LV function and adverse events after a long-term follow-up.