Pericardium is a thin membrane, which envelops the heart and the vascular peduncle (pulmonary trunk, superior vena cava, aorta) formed by mesothelium, or simple pavement epithelium (as peritoneum and pleura ). Two portions can be identified, namely fibrous pericardium and serous pericardium.
- fibrous pericardium → membrane formed by dense connective tissue.
- serous pericardium → internal membrane in turn formed by 2 sheets:
- visceral leaflet: it is the epicardium , which covers the surface of the heart up to the origin of the great vases.
- parietal sheet: leaning against the internal surface of the fibrous pericardium.
The two sheets continue in each other at the level of the base of the heart .
Between the two the pericardial cavity is identified, a virtual space that can become real in case of accumulation of pericardial fluid (pathological condition). This condition, which results from an inflammation of the pericardium, is called pericarditis.
For a better understanding, note that the arrangement of apex and base of heart and pericardium is grossly reversed. In fact, while the apex of the heart is located in the lower part, the apex of the pericardium is located in the upper part, see below.
- base → diaphragm .
- apex → vascular pedicle.
- anterior aspect → mediastinal pleura, sternum (between the pericardium and the sternum is connective present at the level of which the sterno-pericardial ligaments are located). In the child it is related to the thymus, in the adult with adipose lobules.
- posterior aspect → thoracic vertebrae from the 5th to the 9th, esophagus and descending aorta.
The pericardium is anchored in the adventitia habit of the vessels. Forwards it grips the ascending aorta and the pulmonary trunk.
⇑ READ ALSO: Myocardium
⇓ READ ALSO: Fibrous skeleton of the heart