Pericardial Disease

Abstract

The pericardium comprises an inner serous membrane (the visceral pericardium) composed of a single layer of mesothelial cells attached to the cardiac surface and epicardial fat, and an outer fibrous layer (the parietal pericardium). Arterial blood supply is derived from small branches of the aorta, the internal mammary and the musculophrenic arteries, and innervation is via the vagus and left recurrent laryngeal nerves and a rich sympathetic supply from the stellate ganglion and cardiac plexus. The phrenic nerves course over the pericardium en route to the diaphragm. In healthy individuals, the pericardial space contains up to 50 ml of clear fluid, an ultrafiltrate of plasma. The pericardium helps to fix the heart anatomically and reduces friction with surrounding organs. Physiological roles include distribution of hydrostatic forces on the heart, prevention of acute cardiac dilatation and coupling of ventricular diastolic function (‘ventricular interdependence’).