Cardiac Adiposity and Cardiovascular Risk: Potential Role of Epicardial Adipose Tissue

Emerging evidence suggests that cardiac adiposity may play an important role in the development of an unfavorable cardiovascular risk profile. The concept of adiposity of the heart, as new cardiovascular risk factor and marker, is rapidly emerging. Recent papers suggest that epicardial fat, an index of cardiac visceral adiposity could locally modulate the morphology and function of the heart. The close anatomical relationship between epicardial adipose tissue and the adjacent myocardium should readily allow local paracrine interactions between these tissues. Epicardial fat may play a functional and mechanical role in left ventricular hypertrophy, atrial dilatation or diastolic dysfunction. Echocardiography has been recently proposed for the direct assessment of epicardial adipose tissue. Echocardiographic assessment of epicardial fat may be a helpful tool not only for diagnostic purposes, as marker of visceral adiposity and inflammation, but also for therapeutic interventions with weight reduction drugs or pharmaceuticals targeted to adipose tissue. Nevertheless the subject is in its infancy and further studies are needed. In fact it is difficult to determine whether epicardial fat has a direct pathogenic role in the development of cardiac changes. It also remains to be determined whether this location of fat is physiologically or pathologically important and whether it can be used to replace abdominal obesity, or its surrogate marker, waist circumference, as a cardiovascular risk factor. In this article, epicardial adipose tissue's structure, function, method of assessment and reliability as a marker of visceral and cardiac adiposity is briefly reviewed.