Blood or Fat? Differentiating Hemopericardium versus Epicardial Fat Using Focused Cardiac Ultrasound.

Basic point-of-care ultrasound of the heart-also known as Focused Cardiac Ultrasound (FoCUS)-has emerged as a powerful bedside tool to narrow the differential diagnosis of causes of hypotension. The list of causes of hypotension that a FoCUS provider is expected to be able to recognize includes a compressive pericardial effusion due to hemopericardium (blood in the pericardial sac). But hemopericardium can be difficult to distinguish from a more common condition that is not immediately life-threatening: epicardial fat. This paper reviews illustrative images of both epicardial fat and hemopericardium to provide practice guidance to the FoCUS user on how to differentiate these two phenomena.