Incidental Pericardial Fat Pad Does Not Require Cardiology Referral
An incidentally discovered pericardial fat pad is a normal anatomical finding that does not require cardiology referral or any follow-up imaging. 1, 2
Key Distinction: Fat Pad vs. Pathologic Findings
The critical issue is distinguishing a benign pericardial fat pad from other mediastinal or pericardial pathology:
Pericardial fat pads are normal structures composed of fibro-adipose tissue, most commonly located over the anterior portion of the heart, particularly at the right cardiophrenic angle 3
The American College of Radiology Incidental Findings Committee specifically recommends no follow-up for incidental pericardial cysts (which are actual pathologic findings), let alone normal fat pads 2
Normal epicardial and pericardial fat appears as hypodense tissue on CT (attenuation of -190 to -30 HU) surrounding the heart within the pericardial sac 4, 5
What Actually Requires Attention
You should only pursue further evaluation if the imaging suggests something other than a simple fat pad:
Pericardial cysts appear as well-defined, fluid-dense structures (not fat density) and only require intervention if large enough to risk compression of adjacent structures or if symptomatic 2
Pericardial effusions >50 mL indicate significant disease and warrant reporting, but these have fluid density, not fat density 6
Soft tissue masses in the prevascular/anterior mediastinal compartment that are not clearly fat density require characterization and potential follow-up 1
Common Pitfall to Avoid
Do not confuse a prominent pericardial fat pad with a pericardial tumor or mass. 3 The presence of fat attenuation on CT (-190 to -30 HU) definitively identifies this as adipose tissue rather than neoplasm. When a small pericardial effusion is present concomitantly, the fat pad can create a misleading appearance of tumor, but the fat density on imaging clarifies the diagnosis 3.
Clinical Context
While increased pericardial fat volume has been associated with coronary atherosclerosis and metabolic syndrome in research studies 4, 5, 7, an incidental finding of pericardial fat on imaging is: