The term pericardial effusion describes a collection of fluid in the pericardial space.
The amount of fluid may range in volume from a few millilitres up to 2 litres. It may be a transudate (hydropericardium), exudate (pyopericardium) or haemopericardium.
This is a companion discussion topic for the original article at https://patient.info/doctor/pericardial-effusion