Pericardial effusion is extra fluid collecting in the sac around the heart.
Some people have no symptoms, while others develop shortness of breath, chest discomfort, tiredness, cough, fast heartbeat, or difficulty lying flat.
Imaging helps confirm that fluid is present around the heart, estimate how much there is, and look for signs that the heart is being compressed.
Ultrasound, CT, and sometimes chest X-ray can help show the fluid and whether it is affecting the heart.
Treatment depends on the cause and severity and may range from monitoring to urgent drainage.
This entry explains the finding. The next step is having a radiologist interpret your specific scan, not a general definition.