.Original Article………
Evaluation of diagnostic power of Tissue Doppler Echocardiography for assessment of cardiac iron overload in patients with thalassemia major Mozhdeh Dabirian MD1, Rozita Jalalian MD1, Hossein Karami MD2, Mehrnoosh Kowsarian MD3, Abes Ahmadi4, Leila Shokohi MD5, Reza Alizadeh MD, Ph.D Candidate6 1
Assistant Professor of cardiology & fellowship in Echocardiography, Department of Cardiology, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran 2 Associate Professor of Pediatric Oncology, Department of Pediatric oncology, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran 3 Professor of pediatric endocrinology, Thalassemia Research Center, Bouali Sina Hospital, Mazandaran University of Medical sciences, Sari, Iran 4 Resident of Pediatrics, department of Pediatrics, Bouali Sina Hospital, Mazandaran University of Medical sciences, Sari, Iran 5 GP, research Fellow, Research and Technology Department of Mazandaran Medical Science and Health Services, Sari Iran 6 M-Phill course of Ph.D by Research, Molecular and cellular biology research Center, Mazandaran University of Medical Sciences, Sari, Iran Corresponding Authors: Hossein Karami, Associate Professor of Pediatric Oncology, Thalassemia Research Center of Bouali Sina Hospital, Pasdaran Boulevard, Sari, Mazandaran Province, Iran Email:
[email protected] Tel: 2233010-16 Fax: 2234506 Po Box: 4815838477
Abstract Background and Aim: Iron overload in patients with thalassemia major is one of the most important complications of this disease and its cardiac complications are the most important causes of death in these patients.MRI T2 is the perfect device to assess the amount of iron deposited in the heart of thalassemia patients, but it causes waste of time and also is an expensive diagnostic method. Tissue Doppler echocardiography is the newer method for this evaluation.Herein, this study was conducted to determine efficacy and specificity of tissue Doppler echocardiography in the assessment of heart iron overload in patients with thalassemia major. Materials & Methods: It was a diagnostic power assessment research performed on 50 patients with thalassemia major aged ≥ 15 years old that had been visited in BoualiSina Hospital in sari, Iran. After the study was explained and patients agreed to participate, written informed consent was obtained. All the patients underwent MRI T2* and tissue Doppler echocardiography results were obtained. The collected data were processed with SPSS 16 and specificity and efficacy of tissue Doppler echocardiography were obtained. In all analysis, P value< 0.05 was considered statistically significant . Result: Patients were divided into four groups: normal amount of iron in the heart tissue, mild, moderate and severe. There was a good compatibility between results of MRI T2* and tissue Doppler echocardiography. Conclusion: we can offer that tissue Doppler echocardiography is a worthy method for evaluating cardiac complications of iron overload in patients with thalassemia major. Keywords: Diagnostic power, Tissue Doppler Echocardiography, Cardiac Iron Overload, Thalassemia major Received: 18, Jul, 2012 Accepted: 2, Sep, 2012
Introduction Thalassemia is a hereditary anemia characterized by anomalies in the synthesis of one or more of the globin chains of normal hemoglobin.(1) Beta- thalassemia characterized by reduced or absent of beta globin chain synthesis. There are more than 200 beta globin 14
gene mutations in beta- thalassemia2. Based on type of mutations and the level of fetal hemoglobin production, blood transfusions could be started from the first few months to the second year of life in these patients.(2) Blood transfusion is lifesaving in these patients, but it can be increased the risk of viral infection
IJHOSCR 6(4) - ijhoscr.tums.ac.ir – October 1, 2012 International Journal of Hematology Oncology and Stem Cell Research
and iron overload. (1) Congestive heart failure remains the main leading cause of death in thalassemia major patients. (3, 4)
value less than 0.05 was considered as statistically significant. Table 1. Echocardiography and LVEF indices
Materials & Methods This study was approved by the Ethic Committee of Mazandaran University of Medical Sciences and permissions were received from all participants. The aim of the study was to determine the diagnostic value of TDE in thalassemia major patients aged ≥15 years old followed by Bouali Sina Hospital Thalassemia Research Center, Sari/ Iran. Fifty samples were taken according to previous studies.(5) After the study was explained and patients agreed to participate, demographic data, blood levels of ferritin, the number of years the patient received blood transfusion, and other items were extracted from clinical records of the participants. Patients were then sent to the unique MRI T2* center that existed in Sari. MRI index is expressed in milliseconds. Index above the 20 ms means normal storage, 14-20 ms means low iron stores, 10-14 ms is considered medium storage of iron and less than 10 iron storage means severe iron deposition. After that, the patients underwent tissue Doppler echocardiography (TDE) using vivide3 set (Manufactured by GE Co.). The coauthor cardiologist was blind to the results of the MRI. Some of the echocardiographic indices (indices of diastolic and systolic function) measured using TDE were as follows: E- Wave (blood flow through the mitral valve in early diastole), A- Wave (blood flow through the mitral valve during atrial contraction); DT (deceleration time), E- wave slope, E'- Wave (annulus movement of the mitral during early diastole), E / E '(ratio of E- wave to E'), LVEF (systolic function index) 18.Normal levels of echocardiography and LVEF indices are presented in Table- 1. Data were analyzed using SPSS16 software. Measures of central tendency and dispersion, correlation between MRI parameters or echocardiographic indices with Pearson and Spearman correlation coefficient were calculated, and then the results were compared with serum ferritin levels. Sensitivity, specificity and efficiency of echocardiogram were calculated and Roc curve was drawn. P
Moderat Severity Indices
Normal
Mild
e
sever
E/A
1-1.5
