Pericardial Cavity

cavitas pericardialis

The pericardial cavity is the potential space between the visceral pericardium (epicardium) and the parietal pericardium, normally containing 15-50 mL of serous pericardial fluid. The fibrous pericardium is the outermost inextensible layer. The pericardial sinuses — the transverse sinus (posterior to the aorta and pulmonary artery, anterior to the atria) and the oblique sinus (posterior to the left atrium, between the pulmonary veins) — are recesses within the pericardial cavity.

Region: Chest

Clinical Relevance

Clinical Notes

Pericardial effusion accumulates fluid in the pericardial cavity; the fibrous pericardium's inextensibility means that rapid accumulation (as in haemopericardium from aortic dissection or cardiac trauma) produces cardiac tamponade at lower volumes than slowly accumulating effusions. Pericardiocentesis targets the left subxiphoid approach to enter the pericardial cavity safely. The transverse pericardial sinus posterior to the aorta and pulmonary artery is used by cardiac surgeons during coronary artery bypass surgery to pass tapes around these vessels for aortic cross-clamping.

Pathology

Common Injuries & Conditions

Cardiac Tamponade from Acute Haemopericardium

Rapid haemopericardium from penetrating cardiac trauma or aortic dissection accumulates as little as 150-200 mL before the inextensible fibrous pericardium produces cardiac tamponade with Beck's triad of hypotension, elevated JVP, and muffled heart sounds; emergency pericardiocentesis or thoracotomy is required.