Pathology and Cardiotoxicity of the Epicardial Adipose Tissue

Abstract

Intra-organ fatty infiltration is associated with end-organ damages and increased cardiovascular risk. Ectopic fat deposition occurs also within the heart and may cause a metabolic cardiomyopathy. Epicardial fat (EAT) can be considered ectopic fat accumulation of the heart. Epicardial fat and intra-myocardial triglycerides content are related. Excessive EAT can produce lipotoxic effects throughout an abnormal lipid deposition and fatty infiltration in the myocardium. As cardiomyocytes fat storage capacity is very limited, high levels of plasma lipids cause cardiac steatosis, hypertrophy, dysfunction, and ultimately failure, as observed in morbid obesity and uncontrolled diabetes. Due to its anatomical and functional vicinity to the myocardium, EAT can affect the morphology and function of all of the heart chambers. Increased epicardial fat has been largely associated with increased left ventricular mass, abnormal geometry, enlarged atria, and diastolic dysfunction. Multifactorial physical and biomolecular mechanisms can explain the effects of excessive EAT on the heart.