PREVALENCE OF THICKENED EPICARDIAL FAT MEASURED BY TRANS-THORACIC ECHOCARDIOGRAPHY IN EGYPTIAN PATIENTS WITH ATRIAL FIBRILLATION

Abstract

Atrial fibrillation (AF) is the most frequent cardiac arrhythmia in clinical practice. AF is often associated with profound functional and structural alterations of the atrial myocardium that compose its substrate. Recently, a relationship between the thickness of epicardial adipose tissue (EAT) and the incidence and severity of AF has been reported. Adipose tissue is a biologically active organ regulating the metabolism of neighboring organs. It is also a major source of cytokines. In the heart, EAT is contiguous with the myocardium without fascia boundaries resulting in paracrine effects through the release of adipokines. The infiltration of adipocytes into the atrial myocardium could also disorganize the depolarization wave front favoring micro re-entry circuits and local conduction block. The terms epicardial fat, paracardial and pericardial fat, have been used interchangeably through-out the literature, despite differences in location and function. They are often collectively referred to as cardiac ectopic fat or cardiac adipose tissue. Pericardial fat consists of two layers: the visceral, epicardial fat layer and the parietal, paracardial fat layer.