The impact of magnetic resonance imaging in the assessment of iron overload in heart and liver in transfusion-dependent thalassemic children: Minia experience

Background Thalassemia is the most prevalent single-gene disorder. Myocardial and hepatic iron depositions lead to complications and eventually death. We aimed to assess the diagnostic efficacy of magnetic resonance imaging T2* (MRI T2*) in quantifying iron overload in liver and heart in transfusion-dependent B-thalassemia major (TDT) children. Methods Prospective clinical study was carried on sixty children diagnosed with TDT. All of them underwent laboratory investigations, including CBC, serum iron, and ferritin levels. MRI T2* of the heart and liver was carried out to measure the iron overload and estimate the left ventricular ejection fraction (LVEF). Results Thirty-eight males and 22 females with TDT with a mean age of 13.23 years were included. Twenty cases (33.3%) had severe liver iron overload, while 36 (60%) had normal cardiac iron. There was a moderate significant negative association between hepatic and cardiac iron deposition (P = 0.03). All cases with severe cardiac iron overload had impaired LVEF below 56%. A non-significant positive association was noticed between cardiac iron deposition and LVEF in T2* (P = 0.08). A moderate negative significant association was detected between hepatic iron deposition and serum ferritin, while a fair negative significant association was found between serum ferritin and cardiac iron deposition with P values of 0.04 and 0.02, respectively. Conclusion MRI T2* is the gold standard for monitoring and follow-up of iron overload in the heart and liver. It should be routinely performed in all TDT children as liver iron, and serum ferritin do not reflect cardiac iron overload.

Evaluation of the relationship between hepatic and cardiac iron overload with MRI T2* and carotid intima media thickness with Doppler ultrasound in beta thalassemia major patients

Background: Iron overload is caused early progression of atherosclerosis in beta thalassemia patients due to regular repeated blood transfusion. MRI T2* is a gold standard non-invasive method for detecting hepatic and cardiac iron overload. The aim of this study was the comparison of carotid intima media thickness (CIMT) in the patients and healthy control groups with Doppler ultrasound for early diagnosis of atherogenesis. Another purpose was to assess the relationship between CIMT and iron overload among patients. Materials and methods: This cross-sectional study was performed on twenty patients referred to the Sarvar clinic and twenty age- and sex-matched control group. The CIMT was measured with Color Doppler ultrasound in both groups. Then, MRI T2* results, demographic, and therapeutic information were extracted from their documents. Results: CIMT was insignificantly higher in the patients compared to the control group. For example, it was 0.49 ± 0.05 vs. 0.45 ± 0.03 (p = 0.009) for the right common carotid artery (RCCA) and 0.48 ± 0.06 vs. 0.46 ± 0.04 (p = 0.17) for the left common carotid artery (LCCA). There was no strong relationship between CIMT and age (p = 0.09 for RCCA, p = 0.00 for LCCA), sex, chelation type (for example, p = 0.51 for RCCA with Desferal and p = 0.91 for LCCA with Desferal), age at diagnosis, age at the beginning on transfusion (p = 0.49 for RCCA, p = 0.20 for LCCA), age at the start of chelator (p = 0.74 for RCCA, p = 0.78 for LCCA), and hepatic and cardiac iron overload. Conclusion: Preventive and curative methods should be planned to cease its progression. Furthermore, early initiation of chelator drugs with better efficacy and compliance may reverse the hepatotoxic and adverse myocardial effects of excessive iron.

Plasma level of matrix metalloproteinase-9 in patients with sickle cell disease and its correlation to myocardial iron overload

Cardiac iron overload is secondary to chronic blood transfusion in patients with sickle cell disease (SCD). Iron overload cardiomyopathy is a restrictive cardiomyopathy associated with systolic and diastolic dysfunction. Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases responsible for tissue remodeling. Many studies offer strong evidence for the role of MMP-9 in LV remodeling. We aimed to detect plasma levels of MMP-9 in patients with SCD and its correlation to myocardial iron overload. A case control study was carried out on 50 patients with SCD and 50 age and sex matched healthy controls. Assessment of cardiac iron overload in patients by MRI T2* was performed. Plasma MMP-9 levels were measured for patients and controls using ELISA. SCD patients had significantly higher levels of MMP-9 than controls. There was highly significant correlation between plasma levels of MMP-9 and serum ferritin. Patients with vaso-occlusive crises (VOC) > 5/year had significantly higher levels of MMP-9 than those with VOC ≤ 5 /year. No significant correlation was found between MMP-9 and cardiac T2*. MMP-9 seems to be a useful marker in SCD patients. Patients with serum ferritin > 1000 ng/ml, recurrent VOC > 5 /year had significantly higher MMP-9 serum levels than others.

Mobilization of Auto-Stem Cells in the Thalassemia Major and Relationship with Iron Overload

Objectives: The hematopoietic stem cells transplantation (HSCT) is the only curable treatment in current for thalassemia major (TM).The quantity of auto stem cell of TM patients are very important for rescue the patients in case of failure of HSCT, and auto stem cells of TM will be used as target cells for gene therapy (GT) in the near future. Iron overload (IOL) can damage the hematopoiesis of TM. How to collect the auto stem cells in TM patients? How about the affects of iron overload in the mobilization and collection of auto stem cell? The aim of this study was to analyze quantity of auto stem cells in the TM and the affects of iron overload (IOL). Methods: We retrospectively analyzed a total of 134 patients and 25 normal donors undergoing PBSCs collection between January 2012 and December 2019. Patients with serum ferritin levels over 1,000 ng/mL and with a history of red blood cell transfusions prior to stem cell collection were defined as a group having transfusion-associated iron overload (IOL). In total one hundred and thirty-four patients and twenty-five donors were subcutaneous administrated G-CSF (Granulocyte Colony Stimulating Factor) 10 mg/kg/d Injection for 5 days, PBSCs was collected using a large volume leukapheresis (LVL) procedure. The data of WBC, MNC and CD34+ in product were analyzed by SPSS 20 software. Results: In 134 patients, median age is 8.60 range: (1-17),and 25 Normal donors, median age is 7.5 range: (1-18). The results demonstrated that cells either in patients with thalassemia or normal donors were effectively mobilized by G-CSF (10 mg / kg/d),as these children showed a marked increase in white blood cells and MNC cells in peripheral blood, reaching a peak in 4 to 5 days after the injection of G- CSF alone. Comparison of the MNC [(6.7±3.5) ×10⁸/kg vs (7.2±4.77) ×10⁸/kg] and CD34+cells [(10.29±4.5)×10⁶/kg vs (10.9±6.8)×10⁶/kg] in collected product in TM patients and normal donors groups revealed no significant difference. There was no significant difference between different Ferritin level (Mild, Intermediate and Severe) on WBC, MNC, and CD34+ in each group at the time point studied. But there was significant difference on MNC number (Normal liver iron (7.73±2.69)×10⁸/kg, Mild liver iron overload (7.66±4.64)×10⁸/kg, Intermediate (6.18± 2.84) ×10⁸/kg compared to Severe liver iron (4.45±3.34)×10⁸/kg, P=0.039. Significant difference was also can be seen in number of MNC of product in patients with intermediate cardiac iron overload compared to normal cardiac iron overload and mild cardiac iron overload (2.76±0.97) ×10⁶/kg vs(6.86±3.39) ×10⁶/kg and (6.88±3.72)×10⁶/kg, P=0.030. There was a statistically significant difference positive correlation between median age (P=0.011) and MNC/Kg (P=0.030). Conclusion:The quantity of mobilization of PBSC in TM patients had no significant difference compare to normal donor. The MNC in product was statistically decreased in intermediate cardiac iron overload and severe liver iron overload (IOL) subgroup. It indicated that iron overload (IOL) in organs may negatively relate to proliferation and mobilization of stem cells in TM. Further quality study of PBSC such as stem cell culture and ability of proliferation should be more evaluated. The sufficient quantity and high quality auto stem cell from TM patient can be more used in the future. Disclosures No relevant conflicts of interest to declare.

The heart and inherited haematological disorders

This chapter covers inherited haematological disorders. It explains the pathophysiology, genetics, and iron overload of thalassaemia; cardiac disease in both β‎ and α‎thalassaemia; the pathophysiology, genetics, and iron overload in haemochromatosis; the evaluation of patients; and finally the management of patients at risk of cardiac iron overload.

Assessment of the Relationship Between Iron Overload Based on Cardiac T2* MRI and Fragmented QRS in Beta-Thalassemia Major Patients

Background: Cardiac involvement in beta-thalassemia major patients is an important cause of mortality. Therefore, in these patients, timely diagnosis of cardiac disorder is essential. Objectives: The present study aimed at determining the association between cardiac iron overload and fragmented QRS (fQRS). Methods: This cross-sectional study was conducted on 40 β-TM patients, aged 5 - 40 years. The presence of fQRS was evaluated in 12-lead surface electrocardiograms. Cardiac T2* MRI was performed to determine the iron overload. The patients were divided into four groups of chelation therapy. Results: The mean age of patients was reported to be 22.50 ± 6.75 years. The groups showed no significant difference regarding gender, age, or left ventricular ejection fraction. The presence of fQRS was detected in 10 patients (25%), while T2* value was lower than 20 ms in 10 patients (25%). The mean age of patients with and without fQRS was 26.23 ± 2.71 and 19.40 ± 2.61 years, respectively (P = 0.001). The univariate analysis indicated that fQRS had a significant relationship with cardiac iron overload (OR = 5; 95% CI: 1.04 - 23.99; P < 0.044). The multiple logistic regression analysis represented a significant association between iron overload and fQRS (OR = 5.556; 95% CI: 1.027 - 30.049). The sensitivity and specificity of the fQRS against MRI were equal to 50% and 83.3% respectively. Conclusions: The absence of fQRS on ECGs could be a good predictor of the lack of cardiac iron overload in β-TM patients. The results showed that fQRS might indicate the no need for close monitoring for cardiac overload with cardiac MRI and aggressive chelation therapy.