Arterial Supply
The fibrous pericardium and parietal layer of visceral pericardium is supplied by the branches of the following arteries:
- Internal thoracic artery.
- Musculophrenic arteries.
- Descending thoracic aorta.
The visceral layer of serous pericardium is supplied by the coronary arteries.
Nerve Supply
The fibrous pericardium and parietal layer of the serous pericardium are supplied by the phrenic nerves (somatic nerve fibres).
The visceral layer of the serous pericardium is supplied by the branches of sympathetic trunks and vagus nerves (autonomic nerve fibres). Thus fibrous pericardium and parietal layer of the visceral pericardium are sensitive to pain on the other hand visceral layer of pericardium is insensitive to pain. Consequently pain of pericarditis comes from parietal pericardium.
Clinical Significance
Pericarditis And Cardiac Tamponade
The inflammation of the serous pericardium is named pericarditis which causes accumulation of serous fluid in the pericardial cavity, the pericardial effusion. The excessive accumulation of serous fluid in the pericardial cavity may compress the thin-walled atria and interfere together with the filling of the heart during diastole and consequently the cardiac output is diminished. This condition is medically referred to as cardiac tamponade.
The pericarditis is the terminal event in uremia.
Pericardiocentesis
Excessive pericardial fluid can be aspirated from the pericardial cavity by 2 routes:
A. Sternal method: The needle is inserted via the left 5th or 6th intercostal space immediately adjacent to the sternum.
B. Subxiphoid method: The needle is inserted in the left costoxiphoid angle and passed in an upward and backward direction with an angle of 45° to the skin.
Pericardial Friction Rub
The roughening of parietal and visceral layers of the serous pericardium by inflammatory exudate can cause friction between the 2 layers named pericardial friction rub which can be felt on palpation and heard via the stethoscope.