The relationship between the myocardial T2*value and left ventricular volumetric and functional parameters in thalassemia major patients

PURPOSE Cardiac involvement in thalassemia major (TM) is mainly characterized by left ventricular dysfunction caused by iron overload. Cardiovascular magnetic resonance imaging (MRI) including myocardial T2* measurement is becoming increasingly popular for quantitatively evaluating myocardial iron overload. The aim of this study was to evaluate the relationship between the myocardial T2* value and left ventricular functional parameters and to examine the associations between the degree of cardiac iron load and various clinical parameters. MATERIALS AND METHODS A retrospective analysis of 47 patients (25 males and 22 females; mean age, 23.0 +/- 5.4 years) with TM was performed. Myocardial iron load was assessed by T2* measurements, and volumetric functions were analyzed using the steady state free precession sequence. RESULTS In patients with myocardial iron deposition (T2* <20 ms), the mean left ventricular ejection fraction (LVEF) was 64.73 +/- 4.94%. The LVEF of patients with myocardial siderosis was significantly lower than that of patients without myocardial siderosis (r=0.35, P = 0.014). Inverse and significant correlations between both the left ventricular (IN) end-systolic volume index and the LV end-diastolic volume index and the myocardial T2* value (r=-0.32, P = 0.027 and r=-0.29, P = 0.046, respectively) were observed. There was an inverse correlation between the myocardial T2* value and the liver iron concentration (r=-0.31, P = 0.037). Cardiac T2* was not associated with serum ferritin levels, pre-transfusion hemoglobin levels or the annual red cell consumption rate. CONCLUSION Myocardial iron load assessed by cardiac MRI (T2*) is associated with deterioration in left ventricular function. Thalassemia major patients with myocardial siderosis may have LVEF values within normal limits, but this result must be interpreted cautiously.