Comparison of epicardial, abdominal and regional fat compartments in response to weight loss

Background and aims: Echocardiographic measurement of epicardial fat (EF) seems to be a reliable and diagnostic marker of visceral adipose tissue (VAT). However, the weight loss-induced changes in EF have not been compared with those in VAT or the truncal depot. In this study, we aimed to compare the weight loss-induced changes in EF, VAT and other regional fat compartments in obese men. Methods and results: In this study, 27 moderately obese men (age 45.8 ± 1.7 years; body mass index 30.5 ± 0.7 kg/m²) followed a daily low-calorie diet as part of a clinical 12-week weight loss interventional study. We evaluated the EF thickness by transthoracic echocardiography, assessed the abdominal fat tissues by computed tomography scans, and examined the regional and whole body fat compartments by dual X-ray absorptiometry. An average decrease of 26.8% in the initial calorie intake corresponded to post-program reductions of 17.2%, 11.0%, 16.6%, and 29.8% in EF thickness (P < 0.001), body mass, percentage fat mass, and abdominal fat compartments, respectively. The percentage change in VAT in response to weight loss was twice as high as the substantial change in EF tissue (P < 0.001). Conclusion: The results of the study suggest that a low-calorie diet-induced weight loss decreases EF thickness. Moderate diet-induced weight loss alone may represent an effective nonpharmacological strategy for reducing EF, which is a unique, pathogenic fat depot and an emerging marker of VAT.