Cardiac magnetic resonance evaluation of epicardial adipose tissue in hemodialysis patients

Background

Epicardial adipose tissue (EAT) is a predictor of cardiovascular risk in the general population. However, the value of EAT in hemodialysis patients has not been fully validated. The aim of this study was to evaluate the correlation between EAT and cardiac structure and function parameters in hemodialysis patients, and to explore the relationship between EAT and dialysis age.

Methods

Forty patients with chronic kidney disease undergoing regular hemodialysis and five healthy volunteers were enrolled prospectively. All participants underwent cardiac magnetic resonance scanning using balanced steady-state free precession sequence. Images included continuous short-axis views covering the entire left ventricle, two-, three- and four-chamber views. Ventricular function parameters and epicardial fat volume were obtained by post-processing software. On the short-axis cine stack, EAT was delineated from the most apical to basal level of left ventricle at end-diastole. Fat volume was calculated by modified Simpson's rule, with body surface area corrected for individual differences.

Results

Compared with healthy volunteers, EAT in hemodialysis patients was significantly higher (40.7 ± 5.5 ml/m² vs. 62.8 ± 17.3 ml/m², P < 0.001). EAT was positively correlated with left ventricular end-systolic myocardial mass index (r = 0.59, P < 0.001) and left ventricular end-diastolic myocardial mass index (r = 0.61, P < 0.001). There was a negative correlation between EAT and left ventricular global radial strain (r = −0.33, P = 0.038). There was no significant correlation between EAT and hemodialysis age (P = 0.587), left ventricular ejection fraction (P = 0.086), right ventricular ejection fraction (P = 0.331).

Conclusions

Hemodialysis patients have more EAT. EAT was significantly correlated with myocardial mass and global radial strain. Further studies are needed to evaluate the value of EAT in predicting cardiovascular events in hemodialysis patients.