Lecture 1.1a - CVS anatomy

Functions of the Pericardium

• Fixes the heart in the mediastinum, limiting its motion, with the heart sitting on the diaphragm
• Prevents overfilling of the heart, with a normal amount of pericardial fluid ranging from 20-50ml, and overfilling occurring when it reaches 100ml
• Provides lubrication
• Offers protection from infection

Pericardium: Clinical Implications

• Pericardial effusion is the acute or chronic accumulation of fluid within the pericardial space, with reasons including infection, inflammatory conditions, cancer/cancer treatments, trauma, and idiopathic causes
• Pericardial effusion can lead to cardiac tamponade, compressing ventricles and resulting in reduced cardiac output and shock

Innervation of Pericardium

• The phrenic nerve (C3-C5) provides sensory supply to the fibrous and parietal pericardium
• Pain sensations are conveyed by these nerves and are commonly referred to the skin (C3-C5 dermatomes)
• The pericardium is a common source of referred pain in pericarditis

Pericardial Sinuses

• The transverse pericardial sinus is a cavity that brings together the primordial arterial and venous ends of the developing heart
• The pericardial oblique reflection is a cavity that forms as veins expand and pericardial reflection is carried out around them