Epicardial adipose tissue: anatomic, biomolecular and clinical relationships with the heart

Abstract

A growing amount of evidence suggests that regional fat distribution plays an important part in the development of an unfavorable metabolic and cardiovascular risk profile. Epicardial fat is a metabolically active organ that generates various bioactive molecules, which might significantly affect cardiac function. This small, visceral fat depot is now recognized as a rich source of free fatty acids and a number of bioactive molecules, such as adiponectin, resistin and inflammatory cytokines, which could affect the coronary artery response. The observed increases in concentrations of inflammatory factors in patients who have undergone coronary artery bypass grafting remain to be confirmed in healthy individuals. Furthermore, epicardial adipose mass might reflect intra-abdominal visceral fat. Therefore, we propose that echocardiographic assessment of this tissue could serve as a reliable marker of visceral adiposity. Epicardial adipose tissue is also clinically related to left ventricular mass and other features of the metabolic syndrome, such as concentrations of LDL cholesterol, fasting insulin and adiponectin, and arterial blood pressure. Echocardiographic assessment of epicardial fat could be a simple and practical tool for cardiovascular risk stratification in clinical practice and research. In this paper, we briefly review the rapidly emerging evidence pointing to a specific role of epicardial adipose tissue both as a cardiac risk marker and as a potentially active player in the development of cardiac pathology.

Increased Epicardial Adipose Tissue Thickness Is Correlated with Ascending Aortic Diameter

“…They revealed an excellent correlation, compared to gold standard abdominal and epicardial fat measurements using MRI. Echo cardio graphically measured epicardial fat may provide a highly reliable measure of true visceral fat content, avoiding the possible confounding effect of increased subcutaneous abdominal fat (Iacobellis et al 2005a).…”

“…The physiological, biochemical, and biomolecular properties of epicardial adipose tissue and the possible paracrine interactions within the heart have been described in previous studies (Taguchi et al 2001;Iacobellis et al 2005a). EAT exists, mainly in the atrioventricular and interventricular groove along the major coronary arteries and branches, to a lesser extent in the atrium, right ventricle and the left ventricular free wall, and shows extension to the apex (Sacks and Fain 2007).…”

Inflammation of left atrial epicardial adipose tissue is associated with paroxysmal atrial fibrillation

“…EAT is contiguous with cardiac structures; it overlies the right ventricle, coronary arteries, left ventricular apex, and atria, without forming an intervening fascia between these structures [19]. Our study targeted EAT surrounding the LA because the LA plays an important role in AF, particularly around the pulmonary veins.…”

Substantial Changes in Epicardial Fat Thickness After Weight Loss in Severely Obese Subjects

“…Recently, the scientific and clinical interest in epicardial adipose tissue is rapidly growing (3)(4)(5)(6). We showed that echocardiographic assessment of epicardial adipose tissue can serve as a new index of cardiac and visceral adiposity.…”