CARDIAC MAGNETIC RESONANCE IN TRANSFUSION DEPENDENT THALASSAEMIA: ASSESSMENT OF IRON LOAD AND RELATION TO LEFT VENTRICULAR EJECTION FRACTION

International audienceCardiac Magnetic Resonance (CMR) has replaced all other surrogate measurements in the determination of transfusional cardiac iron overload in patients with thalassaemia major. We aimed to determine the diagnostic value of CMR T2* with respect to cardiac dysfunction (CD) as determined by CMR-derived left ventricular ejection fraction (LVEF). Cardiac T2* values and LVEF measured by CMR were recorded in 303 patients with thalassaemia major, at the time of their first CMR. T2* was correlated with LVEF (regression coefficient: 0.57, p 8ms and ≤14 ms and reduced to 9.1% in patients with T2* between 14-20 ms. As the probability of CD is progressively, and not suddenly, reduced with increasing values of T2*, CMR has a limited diagnostic value for cardiac dysfunction (ROC Analysis, AUC = 0.68). Patients with cardiac T2* ≤ 8 ms require careful and intensive management. This risk decreases with increasing values of T2* but even in mildly loaded patients the probability of impaired LVEF is not negligible

Brazilian Thalassemia Association protocol for iron chelation therapy in patients under regular transfusion

In the absence of an iron chelating agent, patients with beta-thalassemia on regular transfusions present complications of transfusion-related iron overload. Without iron chelation therapy, heart disease is the major cause of death; however, hepatic and endocrine complications also occur. Currently there are three iron chelating agents available for continuous use in patients with thalassemia on regular transfusions (desferrioxamine, deferiprone, and deferasirox) providing good results in reducing cardiac, hepatic and endocrine toxicity. These practice guidelines, prepared by the Scientific Committee of Associação Brasileira de Thalassemia (ABRASTA), presents a review of the literature regarding iron overload assessment (by imaging and laboratory exams) and the role of T2* magnetic resonance imaging (MRI) to control iron overload and iron chelation therapy, with evidence-based recommendations for each clinical situation. Based on this review, the authors propose an iron chelation protocol for patients with thalassemia under regular transfusions