Correlation between Myocardial Iron Overload Detected by CMRT2* and Left Ventricular Function Assessed by Tissue Doppler Imaging in Patients with Thalassemia Major

Abstract

Background: Iron overload and cardiac dysfunctions are common complications in patients with thalassemia major (TM). Different imaging methods can be used to detect ventricular dysfunction in these patients. In this study, we aim to understand the value of tissue Doppler imaging (TDI) in the detection of myocardial dysfunction in patients with TM who have been diagnosed with iron overload using cardiovascular magnetic resonance CMRT2*. Methods: In this cross-sectional study, fifty patients with TM diagnosed with iron overload who had no clinical signs and symptoms of cardiac dysfunction were chosen as a case group. The control group included fifty sex- and age-matched healthy participants without a history of cardiac and hematological diseases. TDI, pulsed wave Doppler (PWD), and standard echocardiography were performed to study the left ventricular function, and cardiac iron overload assessed by CMRT2*. Then, the patients with TM were divided into two subgroups and compared with each other. Group 1a includes individuals with T2* value <20 ms and group 1b T2* value >20 ms. Results: There was no significant difference between the standard echocardiography results and PWD parameters of the case and control groups; however, CMRT2* findings and TDI parameters were different between the case and control groups. CMRT2* findings also were not correlated with PWD parameters. In group 1a, CMRT2* findings were negatively correlated with age, E', A', early deceleration time, and isovolumetric relaxation time and positively correlated with E/E' ratio. Finally, PWD and TDI parameters were significantly different between the two subgroups. Conclusion: TDI can detect ventricular systolic and diastolic dysfunctions in earlier stages among patients with iron overload. It seems that TDI could detect abnormalities more accurately, and it is better to consider subclinical cardiac dysfunction in patients with even CMRT2* value of more than 20 ms and reevaluate them in future.