Correlation between pretransfusion hemoglobin and myocardial dysfunction in children with transfusion dependent thalassemia

Background and aim
Transfusion dependent thalassemia (TDT) is a severe form of chronic hemolysis in which patients require regular blood transfusions. Pretransfusion hemoglobin is an important indicator of chronic tissue hypoxia which results in many complications most seriously cardiac complications. Cardiomyopathy is the most serious complication of TDT. This study aimed to assess the correlation between pretransfusion hemoglobin concentration and myocardial dysfunction assessed by echocardiography in children with TDT.


Patients and methods
A total of 60 children with TDT aged from 1 to 16 years with no obvious clinical manifestations of heart failure were included in this study. Pretransfusion hemoglobin was calculated from the mean of pretransfusion hemoglobin concentration of the last three months before the study. Serum ferritin level was measured in all patients. They had echocardiographic examination with M-mode, pulsed wave Doppler, tissue Doppler imaging, and speckle tracking echocardiography modalities. Correlation between pretransfusion hemoglobin concentration and ejection fraction, tricuspid annular plane systolic excursion, E/A ratio, E/e′ ratio, left ventricular global longitudinal strain (LV GLS) and right ventricular GLS (RV GLS) was evaluated.


Results
There was a significant positive correlation between pretransfusion hemoglobin concentration and LV and RV GLS. There was no significant correlation between pretransfusion hemoglobin and ejection fraction, tricuspid annular plane systolic excursion, E/A ratio, and E/è ratio. Pretransfusion hemoglobin level at a cutoff value less than or equal to 8 g/dl could predict the presence of a decrease of LV and RV GLS.


Conclusion
Pretransfusion hemoglobin concentration could predict the presence of LV and RV myocardial dysfunction in children with TDT.