Iron overload parameters and early detection of cardiac disease among Egyptian children and young adults with β-thalassaemia major and sickle cell disease: a cross-sectional study

Abstract

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 investigate cardiac function and cardiac iron and their relation to pancreatic 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-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 study group consisted of 40 βTM and 20 transfusion dependant SCD patients with mean age 13.7 years and 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 with main pulmonary artery diameter (p=0.046), peak late diastolic velocity at septal mitral annulus (p=0.038), peak early diastolic velocity at tricuspid annulus (p=0.001) and mitral annular plane systolic excursion (p=0.01); and negatively with end systolic pulmonary artery pressure (p=0.007). We couldn’t test the predictability of pancreatic T2* in relation to cardiac T2* as only one patient had cardiac T2*<20 ms. Conclusion: Assessment of pancreatic T2* in multi-transfused patients with βTM and SCD can predict myocardial dysfunction. No direct relation between pancreatic iron and cardiac siderosis was detected.