Metabolic syndrome is related to multiple cardiovascular risk factors. Visceral adipose tissue (VAT) plays a key role in metabolic syndrome. Easy detection of VAT could be an important tool to increase knowledge of metabolic syndrome. The objective of this study was to study the relationship of echocardiographic epicardial adipose tissue to anthropometric and clinical parameters of metabolic syndrome. We selected 72 consecutive subjects, 46.5 ± 17.4 yr of age, with a body mass index between 22 and 47 kg/m2. Each subject underwent transthoracic echocardiogram to measure epicardial fat thickness on right ventricle and magnetic resonance imaging to calculate visceral adipose tissue. Anthropometric, metabolic, and cardiac parameters were also evaluated. Echocardiographic epicardial adipose tissue showed a very good correlation with magnetic resonance imaging abdominal VAT and epicardial fat measurement (Bland-Altman plot and linear regression). Multiple regression analysis showed that waist circumference (r2 = 0.428; P = 0.01), diastolic blood pressure (r2 = 0. 387; P = 0.02), and fasting insulin (r2 = 0.387; P = 0.03) were the strongest independent variables correlated with epicardial adipose tissue. Echocardiographic epicardial adipose tissue could be applied as an easy and reliable imaging indicator of VAT and cardiovascular risk.
Epicardial adipose tissue has been recently recognized as a source of bioactive molecules as well as free fatty acids, adiponectin, and inflammatory cytokines. Epicardial fat reflects intraabdominal visceral fat, and the echocardiographic assessment of this tissue is an easy and reliable marker of visceral adiposity. In this study we evaluated whether epicardial adipose tissue is related to insulin sensitivity and glucose metabolism in obese subjects. Thirty obese subjects (20 women and 10 men; mean age, 40.8 +/- 11.5 yr; body mass index, 43 +/- 9.1 kg/m2) were included in this study. No subject was taking drugs or had a history or evidence of metabolic, cardiovascular, respiratory, or hepatic disease. Each subject underwent a transthoracic echocardiogram to evaluate epicardial adipose tissue thickness, a euglycemic hyperinsulinemic clamp to estimate insulin sensitivity, and an oral glucose tolerance test to evaluate glucose tolerance. The thickness of the epicardial adipose tissue on the right ventricle varied between 4 and 17.4 mm. Echocardiographic epicardial adipose tissue was significantly correlated with whole-body glucose uptake index from the clamp and with all indices of insulin resistance and glucose intolerance measured, except the 120-min plasma glucose level after an oral glucose tolerance test. Our study showed that the epicardial fat is significantly related to obesity-related insulin resistance. This finding could be of potential interest in clinical practice and research of obesity-related risk stratification.
1 October 2004 in The American Journal of Cardiology