Evaluation of iron load in transfusion-dependent thalassemia patients using T2* cardiac magnetic resonance imaging, correlation with chelation regimen and serum iron parameters

Objective: To investigate the relationship between cardiac T2* MRI and the chelation regimen used and serum iron parameters commonly used to monitor iron load in transfusion-dependent thalassemia patients. Materials and Methods: In our study, 60 patients aged between 9 and 25 years, diagnosed with transfusion-dependent thalassemia and followed up at the Çukurova University Faculty of Medicine Balcalı Hospital Pediatric Hematology Department, were included. All patients were receiving transfusions, and all except one were undergoing chelation therapy. Demographic data (age, sex, body weight, and height), laboratory findings (ferritin, iron, total iron-binding capacity, and hemoglobin levels), symptoms, and clinical features were obtained from medical records and the hospital data system. The severity of iron overload was classified based on T2* MRI values as normal, mild, moderate, or severe. The mild, moderate, and severe groups were combined into an abnormal group for comparison with the normal group. Results: Among the patients included in our study, 28 (46.7%) were female and 32 (53.3%) were male. The mean age was found to be 17.8 ± 5.4 years. The average cardiac T2* MRI values of the patients was 42.2 ± 52.2 ms. When the patients were grouped according to the severity of iron load in the heart, 49 patients (81.7%) had T2* MRI values greater than 20 ms, indicating normal iron levels. Abnormal iron load was present in 11 patients (18.3%): 1 patient (1.7%) had mild, 4 patients (6.7%) had moderate, and 6 patients (10%) had severe iron load. The average age of the normal group (without iron load) was 17 years (range 9-25), while the average age of the abnormal group (with iron load) was 24 years (range 12-25), with a statistically significant difference between the two groups (p=0.037). Correlation analysis showed a weak negative relationship between the ferritin level and cardiac T2* MRI values at the last visit (r= -0.380). A weak negative correlation was also found between the values of T2* MRI and the duration (months) that ferritin levels were above 2500 (r= -0.357, p=0.005). Patients with longer durations of ferritin levels above 2500 had lower T2* MRI values. Conclusion: Cardiac T2* MRI is a valuable non-invasive tool for quantifying cardiac iron load in patients with major thalassemia. It was observed that cardiac iron overload tends to occur more frequently in older patients. We found a relationship between the ferritin levels with the maximum ferritin value recorded during the follow-up, myocardial iron concentration (MIC) and cardiac T2* MRI value at the last visit in thalassemia patients. Keywords: Transfusion-dependent thalassemia patients, cardiac T2* MRI, Ferritin, iron load