Pericardial sac
A conical sac of fibrous tissue which surrounds the heart and the roots of the great blood vessels. Also called the pericardium.
The pericardium has outer and inner coats. The outer coat is tough and thickened, loosely cloaks the heart, and is attached to the central part of the diaphragm and the back of the sternum (breastbone). The inner coat is double with one layer closely adherent to the heart while the other lines the inner surface of the outer coat with the intervening space being filled with fluid.
This small amount of fluid, the pericardial fluid, acts as a lubricant to allow normal heart movement within the chest.
The word “pericardium” means around the heart. The outer layer of the pericardium is called the parietal pericardium. The inner part of the pericardium that closely envelops the heart is called the visceral pericardium or epicardium.
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A life-threatening situation in which there is such a large amount of fluid (usually blood) inside the pericardial sac around the heart that it interferes with the performance of the heart. The end result, if untreated, is low blood pressure, shock and death. The excess fluid in the pericardial sac acts to compress and constrict […]
- Pericarditis
Inflammation of the lining around the heart (the pericardium) that causes chest pain and accumulation of fluid around the heart (pericardial effusion). There are many causes of pericarditis, including infections, injury, radiation treatment, and chronic diseases.
- Pericardium, parietal
The tough, thickened outer layer of the pericardium. The parietal pericardium loosely cloaks the heart and is attached to the central part of the diaphragm and the back of the breastbone.
- Pericardium, visceral
The double inner layer of the pericardium. One layer of the visceral pericardium closely adheres to the heart, and the other lines the inner surface of the outer (parietal) pericardium. The intervening space is filled with pericardial fluid. Also known as epicardium.
- Pericentric chromosome inversion
A basic type of chromosome rearrangement in which a segment that includes the centromere (and is therefore pericentric) is snipped out of a chromosome, inverted, and inserted back into the chromosome. The feature that makes it pericentric is that the breaks are on both sides of the centromere.