Systolic cardiac function is typically preserved in obese adults, potentially masking underlying declines in cardiomyocyte metabolism that may contribute to heart failure. We used chemical exchange saturation transfer (CEST) MRI, a sensitive method for measurement of myocardial creatine, to examine whether myocardial creatine levels correlate with cardiac structure, contractile function, or visceral fat mass in obese adults. In this study, obese (body mass index, BMI > 30, n = 20) and healthy (BMI < 25, n = 11) adults were examined with dual-energy x-ray absorptiometry to quantify fat masses. Cine MRI and myocardial tagging were performed at 1.5 T to measure ventricular structure and global function. CEST imaging with offsets in the range of ±10 parts per million (ppm) were performed in one mid-ventricular slice, where creatine CEST contrast was calculated at 1.8 ppm following field homogeneity correction. Ventricular structure, global function (ejection fraction 69.4 ± 4.3% healthy versus 69.6 ± 9.3% obese, NS), and circumferential strain (−17.0 ± 2.3% healthy versus −16.5 ± 1.5% obese, NS) and strain rate were preserved in obese adults. However, creatine CEST contrast was significantly reduced in obese adults (6.8 ± 1.3% healthy versus 4.1 ± 2.7% obese, p = 0.001). Creatine CEST contrast was inversely correlated with total body fat% (ρ = −0.45, p = 0.011), visceral fat mass (ρ = −0.58, p = 0.001), and septal wall thickness (ρ = −0.44, p = 0.013), but uncorrelated to ventricular function or contractile function. In conclusion, creatine CEST-MRI reveals a strong correlation between heightened body and visceral fat masses and reduced myocardial metabolic function that is independent of ventricular structure and global function in obese adults.
|Journal||NMR in Biomedicine|
|State||Published - Jul 2019|
Bibliographical noteFunding Information:
We would like to thank Dr Jody L. Clasey and D. Long for assistance with DXA. This project was supported by the American Heart Association National Affiliate (14CRP20380071 to MV), the National Institute of General Medical Sciences (P20GM103527‐07sub5039), and the National Institutes of Health through the National Heart Lung and Blood Institute (RO1HL128592).
We would like to thank Dr Jody L. Clasey and D. Long for assistance with DXA. This project was supported by the American Heart Association National Affiliate (14CRP20380071 to MV), the National Institute of General Medical Sciences (P20GM103527-07sub5039), and the National Institutes of Health through the National Heart Lung and Blood Institute (RO1HL128592).
© 2019 John Wiley & Sons, Ltd.
- CEST MRI
ASJC Scopus subject areas
- Molecular Medicine
- Radiology Nuclear Medicine and imaging