400 Relationship between Cardiac Iron and Altered Myocardial Substrate in Patients With Chronic Kidney Disease – Non-Invasive Assessment With CMR.

Abstract

Patients with chronic kidney disease (CKD) are at increased risk for cardiovascular complications, and dialysis patients often receive iron supplementation. Cardiac magnetic resonance (CMR) allows evaluation of cardiac function, fibrosis and iron deposition. We used CMR to explore mechanistic links between cardiac iron and abnormal myocardial substrate in patients with CKD. Cardiac function and morphology, tissue characterisation and iron deposition were compared in 24 healthy controls,10 patients with CKD stage 3-5, and 30 patients dialysed for >1 year. There were no between group differences in left ventricular (LV) ejection fraction (65±5 v 62±7 v 61±10%, p=0.908), end diastolic volume (84±16 v 69±13 v 76±22 ml/m2, p=0.532) or left atrial size (21±5 v 22±4 v 23±7m2, p=0.473). LV mass (58±13 v 66±9 v 76±27 g/m2, p=0.005) and global longitudinal strain (-22±3 v -20±4 v -14±4%, p<0.001) were abnormal in the dialysis group, but not the CKD group. Native T1 and T2 times were increased in both CKD and dialysis patients (ShMOLLI 1127±43 v 1189±37 v 1223±61ms, p<0.001; and T2 FLASH 35±2 v42±4 v 39±2ms, p<0.001). No group had significant iron deposition by T2-star. Despite no significant myocardial iron deposition, CMR detects abnormal myocardial structure and function across the spectrum of CKD, with abnormal global longitudinal strain seen only in dialysis patients. CMR may aid in identifying CKD patients at higher risk of adverse cardiac outcomes.