Epicardial visceral fat in obesity

ABSTRACT

Epicardial fat, which is the fat surrounding the heart has been recently studied as a method of visceral adipose tissue prediction. The role of visceral fat has been previously linked to the insulin resistance and metabolic syndrome and its associated increased cardiovascular risk. So, the aim of this study was to determine the epicardial fat thickness in obese subjects and to correlate the findings to anthropometric and metabolic parameters of the metabolic syndrome and insulin sensitivity. The study included 38 obese [BMI women of matched age. Clinical evaluation of the study groups was done with stress on anthropometric measurements [BMI, waist circumference, hip circumference waist hip ratio I and blood pressure measurements. Laboratory evaluation included fasting glucose, insulin and lipids. Assessment of insulin sensitivity was done using the homeostasis model assessment [HOMA -IR] calculated using the fasting glucose and insulin levels. Imaging studies included echocardiography for measurement of epicardial fat as well as abdominal ultra-sonographic measurement of subcutaneous and visceral fat and detection of fatty liver. Using the ATP III criteria for the metabolic syndrome, obese subjects were divided into group A [16 subjects I having metabolic syndrome and group B [22 subjects] not having metabolic syndrome. The study showed significant increase in epicardial visceral fat and intra-abdominal visceral fat thickness in obese subjects in comparison to control group and in group A versus group B subjects, while subcutaneous fat measurements showed non-significant difference between group A and B. Epicardial fat showed significant correlation with waist circumference fasting insulin, HOMA-IR and intra-abdominal visceral fat . On the other hand non-significant correlation with BMI, age blood pressure, fasting glucose and lipids as well as subcutaneous fat, was found. It was concluded that epicardial fat is a simple measure that can be added to routine echocardiograph reflecting the visceral adipose tissue and possible predictor of metabolic syndrome and cardiovascular risk .However further studies including large number of cases are required to determine the reference values of epicardial fat thickness in order to be help full in clinical practice