The Role of Inflammation in Epicardial Adipose Tissue in Heart Diseases

Epicardial adipose tissue is not only a specific adipose tissue depot but also an active endocrine organ producing numerous substances with an important role in the development of obesity-related heart diseases. It is located between myocardium and visceral pericardium and consists predominantly of adipocytes, immunocompetent cells, ganglia and interconnecting nerve branches. Several studies documented a positive correlation between pericardial and epicardial fat and left ventricular hypertrophy and septal thickening, leading to diastolic dysfunction, electrocardiographic abnormalities and facilitating cardiac failure. The cellular cross-talks between epicardial fat and myocardium may include both the vasocrine and the paracrine mechanisms. Adipokines secreted from epicardial adipose tissue, vascular and stromal cells diffuse into interstitial fluid crossing the adventitia, media and intima and modulate cardiac function and cardiomyocyte phenotype and survival. In this article, we review the significance of epicardial adipose tissue and its association with cardiovascular diseases, cellular interactions between epicardial fat and myocardium, secretions of adipokines and inflammatory mediators and a potential of epicardial fat as a therapeutic target for the prevention of obesity-related heart diseases.