The pericardium is a protective sac that contains a small amount of lubricant, which limits the movement of the heart in the ribcage and protects the heart from mechanical injury or infection from nearby areas.

Digital subtraction angiography and placement of an inferior vena cava filter is a measure to prevent the movement of blood clots to the heart and lungs. This is a relatively safe and highly effective method in preventing pulmonary embolism.