Contenu connexe



  1. PERICARDIUM • Pericardium • Conical fibroserous sac • Encloses heart and roots of great vessels • Lies within middle mediastinum • Apex Fused with outer adventitia of great vessels • Base lies on central tendon of Diaphragm • Lies behind the body of sternum and second –sixth costal cartilages • Posteriorly, related – esophagus, descending thoracic aorta, and bodies of 5th to 8th thoracic vertebrae 1 Human Anatomy/Yogesh Sontakke
  2. Functions of Pericardium • Protection of heart (shock absorption) • Restriction of excessive movements of heart • Prevention of overexpansion of heart • Prevents kinking of great blood vessels • Minimizes friction between heart and surrounding structures • Mechanical barrier for spread of infection 2 Human Anatomy/Yogesh Sontakke
  3. Human Anatomy/Yogesh Sontakke 3 Parietal layer is continuous with visceral layer
  4. Subdivisions of pericardium Fibrous pericardium • Outer layer of pericardium • Single-layered, thick, and cone-shaped sac encloses heart and fuses with roots of major vessels Serous pericardium • Inner double-layered blind sac of pericardium • Two layers: • Parietal layer: Lines inner surface of fibrous pericardium • Visceral layer or epicardium: Lines outer surface of heart and great blood vessels • Except at cardiac groove visceral layer is not attached to epicardium due to separation by cardiac vessels Human Anatomy/Yogesh Sontakke 4
  5. FIBROUS PERICARDIUM • Cone-shaped • Thick sac of fibrous connective tissue Features of Fibrous Pericardium • Conical and has apex and base • Apex – directed above and blends with external coats of ascending aorta and pulmonary trunk • Base – broad and fuses with central tendon of diaphragm Human Anatomy/Yogesh Sontakke 5
  6. Features of Fibrous Pericardium • Anteriorly – Connected with sternum by superior and inferior sternopericardial ligaments • Posteriorly – related – principal bronchi, esophagus, and descending thoracic aorta • On each side – related – mediastinal pleura, phrenic nerves, and pericardiophrenic vessels • Protects and keeps heart in place • Prevents over distension of heart and kinking of great vessels Human Anatomy/Yogesh Sontakke 6
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  8. SEROUS PERICARDIUM • Thin, double-layered serous sac lies within fibrous pericardium • Lined by simple squamous epithelium called mesothelium Layers of Serous Pericardium Consists of two layers Parietal layer • Outer layer and lines inner surface of fibrous pericardium, blends with fibrous pericardium Human Anatomy/Yogesh Sontakke 8
  9. Layers of Serous Pericardium Visceral layer (epicardium) • Inner layer, covers external surface of heart and root of great vessels • Separated from heart (specially along cardiac grooves) by subserous areolar and fatty tissue, and blood vessels • Visceral layer – continuous with parietal layer along roots of great blood vessels Human Anatomy/Yogesh Sontakke 9
  10. PERICARDIAL CAVITY •Potential space between parietal and visceral layers of serous pericardium •Normally, contains small amount of serous fluid (15–20ml) •Pericardial fluid reduces friction within pericardium during movements of heart by lubricating opposed surfaces of serous pericardium Human Anatomy/Yogesh Sontakke 10
  11. CONTENTS OF PERICARDIUM 1. Heart with its vessels and nerves 2. Ascending aorta 3. Pulmonary trunk 4. Lower half of superior vena cava 5. Terminal part of inferior vena cava 6. Terminal part of pulmonary veins Human Anatomy/Yogesh Sontakke 11
  12. BLOOD SUPPLY Blood Supply •Fibrous and parietal layer of visceral pericardium •Arterial supply: Branches of internal thoracic, musculophrenic arteries, and descending thoracic aorta •Venous drainage: Azygos and internal thoracic veins •Visceral pericardium •Arterial supply: Coronary arteries •Venous drainage: Coronary sinus Human Anatomy/Yogesh Sontakke 12
  13. NERVE SUPPLY As fibrous and parietal pericardium develop from somatopleuric mesoderm •Supplied by phrenic (somatic) nerves and they pain sensitive •As visceral pericardium develops from splanchnopleuric mesoderm •Supplied by branches of sympathetic trunk and vagus nerve (autonomic nerves) •Insensitive – pain Human Anatomy/Yogesh Sontakke 13
  14. SINUSES OF PERICARDIUM •Communicating zones –developed by reflection of serous pericardium •Two sinuses of pericardium •Transverse sinus •Oblique sinus Human Anatomy/Yogesh Sontakke 14
  15. Reason behind sinuses of pericardium • Visceral pericardium forms two tubes around great vessels of heart as follows • One arterial tube around embryonic arterial end of heart later forms ascending aorta and pulmonary trunk • Another venous tube around embryonic venous end of heart later forms superior and inferior venae cavae and forms pulmonary veins • Initially, arterial and venous ends connected by dorsal mesocardium Human Anatomy/Yogesh Sontakke 15
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  17. Transverse Sinus • Horizontal passage between anterior arterial end and posterior venous end of heart • Develops on degeneration of dorsal mesocardium Boundaries • Anterior: Ascending aorta, pulmonary trunk • Posterior: Superior vena cava • Inferior: Left atrium • Superior: Bifurcation of pulmonary trunk • On each side: Opens into main pericardial cavity Human Anatomy/Yogesh Sontakke 17
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  19. Oblique Sinus •Cul-de-sac behind left atrium •Recess of serous pericardium enclosed by J-shaped sheath of visceral pericardium –encloses six veins • Superior and inferior venae cavae and four pulmonary veins Human Anatomy/Yogesh Sontakke 19
  20. Oblique Sinus Development •Oblique sinus develops due – Absorption of pulmonary vein in developing left atrium → formation of 4 pulmonary veins •Absorption of sinus venosus in developing right atrium → separation of SVC from IVC Human Anatomy/Yogesh Sontakke 20
  21. Oblique Sinus Boundaries • Anterior: Left atrium • Posterior: Parietal pericardium right: Two right pulmonary veins and inferior vena cava • On the left: Two left pulmonary veins • Superior: Reflection of visceral pericardium along right and left superior pulmonary veins (along upper margin of left atrium) • Inferior: Communicates with main pericardial cavity Human Anatomy/Yogesh Sontakke 21
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  24. Clinical Integration • Significance of transverse pericardial sinus • During cardiac surgery, temporary ligature may be passed through transverse sinus to block blood flow through aorta and pulmonary trunk • Pericarditis: Inflammation of pericardium • Pericardial friction rub • In pericarditis, smooth opposing surfaces of serous pericardium become rough • Results in pericardial friction rub • Can be heard as rustle of silk with use of stethoscope Human Anatomy/Yogesh Sontakke 24
  25. Clinical Integration •Pericardial effusion •Accumulation of excessive fluid in pericardial cavity •Causes: Congestive heart failure, pericarditis, tuberculosis, kidney failure, heart surgery, and so on •Symptoms of pericardial effusion rises due – pressure on heart and prevention of complete filling of chamber of heart •Includes chest pain Human Anatomy/Yogesh Sontakke 25
  26. Clinical Integration • Pericardial effusion • Pressure on heart and prevention of complete filling of chamber of heart • Water-bottle heart on chest radiograph • Has enlarged cardiac shadow in form of shape of flask or water bottle • Cardiac tamponade • Compression of heart – Due – inelastic nature of tough fibrous pericardium • Reduces filling of cardiac chambers during diastole and thus reduces cardiac output Human Anatomy/Yogesh Sontakke 26
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  28. Pericardiocentesis •Aspiration of fluid from pericardium •Position of patient •Supine, head end of bed raised by 30°–60° to bring heart closer – anterior chest wall •Procedure Can be done using two approaches Human Anatomy/Yogesh Sontakke 28
  29. Pericardiocentesis Procedure •Subxiphoid approach •Needle inserted in left costoxiphoid angle with upward inclination of about 45° – skin •Parasternal route •Needle introduced into left 5th or 6th intercostal space – left sternal border under ultrasound guidance •Preferred elective procedure Human Anatomy/Yogesh Sontakke 29
  30. Thank you…………. 30