Evaluation of myocardial perfusion and function in patients with asymptomatic beta-thalassemia major using myocardial gated single-photon-emission computed tomography

This study was conducted to evaluate the cardiac perfusion and function of patients with beta-thalassemia major (TM) using99mTc-MIBI cardiac gated single-photon-emission computed tomography (SPECT) and to compare the obtained indices with echocardiographic and hematological parameters. Patients with TM who were referred for regular blood transfusion and periodic checkup were included in this study. A questionnaire containing demographic and medical data was provided for all patients by an expert pediatrician. All of the patients were on Desferal chelation therapy and none of them had clinical signs of heart failure. Myocardial gated perfusion SPECT, echocardiography, and complete blood tests were performed for each patient. In total, 24 patients including 14 men (58.3%) and 10 women (41.7%) aged 15-36 years with a mean age of 24.3 +/- 6.5 years' old were enrolled in this study. Myocardial perfusion scan (MPS) was normal in all patients. The mean value of the measured left ventricular ejection fraction (LVEF) was 58.88 +/- 13.45%. There was no significant association between measured LVEF on scan and echocardiography (P > 0.05). In terms of hematological results, there was a significant association between the hemoglobin and ferritin level and the amount of blood transfusion (P = 0.02 and P= 0.00, respectively). According to the results of myocardial perfusion imaging (MPI), cardiac perfusion and LVEF were within normal limits in all asymptomatic patients. In the absence of any perfusion abnormality, the use of MPI in patients with asymptomatic beta-TM is not recommended for diagnosing myocardial ischemia.