Hemopericardium

-The fat attenuation linear density represents epicardial fat between the pericardial space and the myocardium.

The CT shows blood attenuation fluid surrounding the heart in the pericardial sac.

Hemopericardium refers to an accumulation of blood in the pericardial sac of the heart. Causes include spontaneous trauma versus iatrogenic trauma. Hemopericardium may cause cardiac tamponade.

http://eradiology.bidmc.harvard.edu/Classics/item.aspx?section=Emergency+Radiology&labelpk=33f0adab-853f-4010-a0e2-0756b3f1eac5&pk=fd246f06-b01b-4074-9fc9-8e239718618a