A pericardial effusion is excess fluid between the heart and the sac surrounding the heart, known as the pericardium. Most are not harmful, but they sometimes can make the heart work poorly.
The pericardium is a tough and layered sac. When your heart beats, it slides easily within it. Normally, 2 to 3 tablespoons of clear, yellow pericardial fluid are between the sac’s two layers. That fluid helps your heart move easier within the sac.
If you have a pericardial effusion, much more fluid sits there. Small ones may contain 100 milliliters of fluid. Very large ones may have more than ￼2 liters.
In most cases, inflammation of the sac, a condition called pericarditis, leads to the effusion. As it becomes inflamed, more fluid is produced.
When inflammation of the sac causes a pericardial effusion, the main symptom is chest pain. It may get worse when you breathe deeply and better when you lean forward.
Other symptoms may include:
- Muscle aches
- Shortness of breath
- Nausea, vomiting, and diarrhea (if you have a virus)
￼￼￼￼When there’s no inflammation of the sac, there are often no symptoms.
Large, serious pericardial effusions, or smaller ones that develop quickly, may cause symptoms that include:
- ￼￼Shortness of breath
- Palpitations (sensation that the heart is pounding or beating fast)
- Light-headedness or passing out
- Cool, clammy skin￼￼
A pericardial effusion with these symptoms is a medical emergency and may be life-threatening.
Because these often cause no symptoms, they’re frequently discovered after the results of routine tests are abnormal. These tests can include:
Physical examination: A doctor may hear abnormal sounds over the heart that can suggest inflammation. However, pericardial effusions usually can’t be found through a physical.
Electrocardiogram (EKG): Electrodes placed on your chest trace the heart’s electrical activity. Certain patterns on an EKG can signal a pericardial effusion or the inflammation that leads to it.
￼Chest X-ray film: The heart’s silhouette on one may be enlarged. That’s a sign of a pericardial effusion.
If one is suspected, the best test to confirm it is an echocardiogram (ultrasound of the heart) because your doctor would easily see any excess fluid.