Relationships between total and regional adiposity and epicardial fat in obese women: how can dual-energy X-ray absorptiometry be associated with echocardiographic epicardial fat measurements?

Our aim was to analyse in a population of obese women the relationship between the amount of epicardial fat as measured by transthoracic echocardiography (US) and the parameters of regional adiposity by dual-energy X-ray absorptiometry (DXA), with particular reference to a new software for visceral fat assessment and to a new ‘heart-suited’ regions of interests (ROIs). Sixty patients who satisfied technical inclusion criteria underwent whole-body DXA scan and US on the same day. Total and android fat mass (FM) and FM percentage (FM%) were considered as well as visceral fat (VAT) subcompartment in the android region; moreover, six new ROIs were designed on whole-body DXA images for the investigation of adiposity parameters at heart level. US provided epicardial fat thickness (EPIthickness) and area (EPI-area), as measured following previously validated methods. Body mass index (BMI), gynoid and lower limbs (FM and FM%) were found not statistically correlated with EPI-thickness. The highest correlation was achieved by trunk FM (and FM%, with r = 0.544 and 0.480 respectively, P < 0.001), followed by ROI-1 FM (ROI-1 was drawn following thoroughly the cardiac profile), and android FM. Multivariate analysis including age, weight, BMI, trunk FM and the new ROIs (added one by one), retained in the final model trunk FM. Correlations of DXA with EPI-area were superimposable. In obese women, VAT or other new-designed ROIs are not better correlated than traditional ROIs (i.e. trunk) with epicardial fat amount.