Document Type : Original Article(s)

Authors

1 Assistant Professor, Physiology Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran

2 Associate Professor, Cardiovascular Research Center, Institute of Basic and Clinical Physiology Sciences, Kerman University of Medical Sciences, Kerman, Iran

3 Cardiologist, Endocrinology and Metabolism Research Center, Institute of Basic and Clinical Physiology Sciences, Kerman University of Medical Sciences, Kerman, Iran

4 Assistant Professor, Atherosclerosis and Coronary Artery Research Center, Academic Status, Birjand University of Medical Sciences, Birjand, Iran

5 PhD Candidate, Research Center for Modeling in Health, Institute for Futures Studies in Health, Kerman University of Medical Sciences, Kerman, Iran

Abstract

BACKGROUND: The assessment of cardiac iron overload in thalassemia major has been considered as an important predictive factor of heart injury. The magnetic resonance imaging (MRI)-derived relaxation time parameter (T2*) varies inversely with iron level, and elevated myocardial iron levels by T2* are associated with depressed left ventricular (LV) ejection fraction (EF). We compared echocardiographic (ECHO) indices of systolic function to myocardial T2* in these patients. METHODS: A cross-sectional database review identified 200 consecutive patients with thalassemia who underwent both ECHO and MRI T2* assessment. RESULTS: There was a negative correlation between T2* measurement and ECHO EF (r = −0.389, P < 0.001). Using a cutoff value of 50% for differentiating LV normal and abnormal function by ECHO, T2* MRI had a sensitivity of 57.1%, a specificity of 89.9%, and an accuracy of 86.5% for predicting LV dysfunction. Receiver operating characteristic analysis showed that cardiac iron measurement had an acceptable value for discriminating normal and abnormal LV function (area under the curve = 0.769, 95% confidence interval: 0.653-0.885). With respect to the relationship between serum ferritin level and cardiac iron value, the level of serum ferritin was positively correlated with the level of cardiac iron load (r = 0.257, P < 0.001). Conclusion: Myocardial iron load assessed by MRI T2* is associated with deterioration of the LV function assessed by ECHO with a high specificity and moderate sensitivity. It is important to identify the thalassemic patients with a risk of iron overloaded cardiomyopathy and heart failure.  

Keywords

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