The pericardium is a thin, two-layered, fluid-filled sac that covers the outer surface of the heart. It shields the heart from infection or malignancy and contains the heart in the chest wall. It also prevents the heart from over-expanding when blood volume increases, which keeps the heart functioning efficiently.
Conditions that may affect the pericardium include:
Last reviewed by a Cleveland Clinic medical professional on 01/07/2019.
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