On T2* Magnetic Resonance and Cardiac Iron

Background-Measurement of myocardial iron is key to the clinical management of patients at risk of siderotic cardiomyopathy. The cardiovascular magnetic resonance relaxation parameter R2* (assessed clinically via its reciprocal, T2*) measured in the ventricular septum is used to assess cardiac iron, but iron calibration and distribution data in humans are limited. Methods and Results-Twelve human hearts were studied from transfusion-dependent patients after either death (heart failure, nϭ7; stroke, nϭ1) or transplantation for end-stage heart failure (nϭ4). After cardiovascular magnetic resonance R2* measurement, tissue iron concentration was measured in multiple samples of each heart with inductively coupled plasma atomic emission spectroscopy. Iron distribution throughout the heart showed no systematic variation between segments, but epicardial iron concentration was higher than in the endocardium. The meanϮSD global myocardial iron causing severe heart failure in 10 patients was 5.98Ϯ2.42 mg/g dry weight (range, 3.19 to 9.50 mg/g), but in 1 outlier case of heart failure was 25.9 mg/g dry weight. Myocardial ln[R2*] was strongly linearly correlated with ln [Fe] (

ON T2* MAGNETIC RESONANCE AND CARDIAC IRON

Background: Measurement of myocardial iron is key to the clinical management of patients at ris