Sinuses of the pericardium


These are created where the parietal pericardium becomes continous with the visceral pericardium.

 
1.The transverse sinus:
  • Located between the aorta and pulmonary trunk anteriorly and the left atrium and superior vena cavae posteriorly.

  • It connects the two sides of the pericardial cavity.
 
2.The oblique sinus:
  • Located between the pulmonary veins and inferior vene cavae posterioly and the left atrium anteriorly.

  • It is a blind sac (cul de sac).
   

Attachment of the pericardium:

 

Inferiorly: Central tendon of the diaphragm and fuses with tunica adventitia of inferior vena cava.

Superiorly: Fuses with tunica adventitia of the great arteries and of superior vena cava

Laterally: Fuses with tunica adventitia of pulmonary veins

Anteriorly: Attached to the sternum by the sternopericardial ligaments (superior and inferior)

   

Functions of the pericardium  
  • Encloses and protects the heart

  • Limits unnecessary movements of the heart

  • Prevents unnecesary distention of the heart
   

Blood supply of the pericardium

 

The visceral pericardium is supplied and drained by the coronary system

The parietal and fibrous pericardium receive arterial blood from the following sources:

  • Pericardiophrenic and musculophrenic branches of the internal thoracic artery
  • Pericardial branches from
    -Bronchial

    -Esophageal

    -Superior phrenic arteries.

The veins drain into the azygous system and internal thoracic veins.


Lymphatics of the pericardium:

 

These mainly drain into the following groups of lymph nodes:

  • Parasternal

  • Tracheobronchial

  • Supradiaphragmatic

  • Posterior mediastinal
   

Innervation of the pericardium

 

The visceral pericardium receives autonomic innervation from the cardiac plexus

The parietal and fibrous pericardium are innervated mainly by the phrenic nerve.

 

The Middle Mediastinum, Heart and Pericardium and the Superior Mediastinum