Ectopic Fat Deposition and Diabetes Mellitus

We read with interest the paper by Levelt et  al.(1) in a recent issue of theJournal, which deciphered the parameters that give rise to ectopic fat deposition in insulin-resistant states, such as type 2 diabetes (T2D). One of the strengths of this study is the use of multiparametric cardiovascular and liver magnetic resonance imaging (MRI), and proton and phosphorus magnetic resonance spectroscopy, allowing a comparison of epicardial adipose tissue (EAT), myocardial and hepatic triglyceride content, hepatic fibroinflammatory changes, but also cardiac function and energetics between lean healthy and lean and obese subjects with T2D. One of the study limitations is that epicardial fat volume was not measured in lean healthy subjects, so that the increase in EAT was only validated in 33 subjects with T2D without control subjects. However, MRI was performed in all subjects, and one could expect that the authors assessed EAT with MRI. Indeed, MRI offers excellent spatial resolution; it is now recognized to be the gold standard for adipose tissue imaging and superior to computed tomography in separating epicardial from pericardial fat, the latter of which has different vascularization and developmental origin from EAT. Moreover, it is also the only imaging modality in which volumetric quantification of EAT has been validated ex  vivo(2). In this setting of body fat distribution, the different ectopic fat depots need to be distinguished, and we tend to disagree with the concept of...
Source: Journal of the American College of Cardiology - Category: Cardiology Source Type: research