Cardiac T2 * Magnetic Resonance for Prediction of Cardiac Complications in Thalassemia Major

Background—The goal of this study was to determine the predictive value of cardiac T2 * magnetic resonance for heart failure and arrhythmia in thalassemia major. Methods and Results—We analyzed cardiac and liver T2 * magnetic resonance and serum ferritin in 652 thalassemia major patients from 21 UK centers with 1442 magnetic resonance scans. The relative risk for heart failure with cardiac T2* values 10 ms (compared with 10 ms) was 160 (95 % confidence interval, 39 to 653). Heart failure occurred in 47% of patients within 1 year of a cardiac T2 * 6 ms with a relative risk of 270 (95 % confidence interval, 64 to 1129). The area under the receiver-operating characteristic curve for predicting heart failure was significantly greater for cardiac T2 * (0.948) than for liver T2 * (0.589; P0.001) or serum ferritin (0.629; P0.001). Cardiac T2 * was 10 ms in 98% of scans in patients who developed heart failure. The relative risk for arrhythmia with cardiac T2 * values 20 ms (compared with 20 ms) was 4.6 (95 % confidence interval, 2.66 to 7.95). Arrhythmia occurred in 14 % of patients within 1 year of a cardiac T2 * of 6 ms. The area under the receiver-operating characteristic curve for predicting arrhythmia was significantly greater for cardiac T2 * (0.747) than for liver T2 * (0.514; P0.001) or serum ferritin (0.518; P0.001). The cardiac T2 * was 20 ms in 83 % of scans in patients who developed arrhythmia. Conclusions—Cardiac T2 * magnetic resonance identifies patients at high risk of heart failure and arrhythmia from myocardial siderosis in thalassemia major and is superior to serum ferritin and liver iron. Using cardiac T2 * for the early identification and treatment of patients at risk is a logical means of reducing the high burden of cardiac mortality in myocardial siderosis