Anatomy and physiology of the pericardium

The pericardium is a membranous sac surrounding the heart and the roots of the great vessels that is composed of both fibrous and serosal layers (Fig. 1.1). The fibrous layer of pericardium forms a conical-like sac surrounding the heart; superiorly, the fibrous pericardium is attached to and is continuous with the adventitia of the great vessels as well as with the pretracheal fascia. The pericardium is attached anteriorly to the manubrium and xiphoid process by the sternopericardial ligaments, posteriorly to the vertebral column and inferiorly to central tendon of the diaphragm. The pericardium is separated from the anterior thoracic wall by the lungs and pleura but is in direct contact with it at the lower left half of the sternum and the sternal abutments of the left fourth and fifth costal cartilages [1]. The phrenic nerves contained within the pericardiophrenic bundles pass laterally along each side of the heart between the fibrous pericardium and mediastinal pleura. The serosal pericardium consists of two layers, a serous visceral layer (epicardium) that is adherent to the heart and epicardial fat and a serous layer which lines the internal surface of the fibrous pericardium together forming the parietal pericardium.