Pericardium - My Lecture Note

PERICARDIUMThe pericardium is a fibroserous sae which encloses theheart and the roots of its great vessels (blood)LOCATION/SITUATION:- Pericandium lies -(1) Within the middle mediastinum. DIRANMARRAM(2) Posterior to the body of the Sterum(3) 2nd to 6th Costal Cartilage (between)(4) Anterior to the middle four thoracic vertebrae.FUNCTIONS: -1Restricts excessive movements of the heart.2and Serves as a lubricated container in which heart can contractrelax smoothly3Limits the Cardiac distension.SUBDIVISIONSThe pericardium consists of 2 components -(1) FIBROUS SEROUS PERICARDIUM (Ourer Single layered)(2) PERICARDIUM (Inner double layered)FIBRUUS PERICARDIUMDIPANKAR RAY.It of the is a Strong fibrous Sac which supports delicate parietal layerIt is conical serous in pericandium shape. with which it is fimly adherent.(i)Apex 1 - It Blunt is fused and with lics at the level of the Sternal angle.and with pretracheal fascia.the the roots of the great vessels(ii) Base:- tendon Broad and inseparably blended with the centralof diaphragm.(iii) Anteriorly:- (upper Connected to the posterior aspect of the bodyinferior Stemopericardial and lower ligaments. ends) by weak Superior and(N) with Posteriorly:- the nerve Related to the principal bronchi, the Oesophagus(vi) Each Side:- Related to phrenic N; Mediastinal Pleura,On plexus around it and the descending thoracic Gerrapericardio phrenic vessels. lung (Mediastinal surface) PERICARDIUMSEROUS PERICARDIUM1Serous pericardium is thin, double-layered serous membranelined by mesothelium.(2) Outer layer or parietal pericardium is fused with the fibrouspericandium(3) The inner layer or the visceral pericardium or epicardiumis fused to the heartDIPANKAR RAYfrom the heart by blood vessels.except along the cardiac grooves, where it is separated(4) The two layers are continuous with each other at theroots of the great vessels. ie - Ascending aorta, Pulmonarytrunk, two Vena Cava and Pulmonary vein (4)-PERICARDIAL CAVITY1Pericardial cavity is a slit like potential space between theparietal layer and visceral layer of Serous pericardium.2Called Normally it contains a thin film of serous fluid (50ml Approx)surfaces Pericardial fluid". which lubricates theto avoid friction during the movements opposed of heart. PERICARDIUMSINUSES OF PERICARDIUMThere are two sinuses between the parieral andviseral layers of Serous pericardium.ITRANSVERSE SINUS2OBLIQUE SINUS.1TRANSVERSE SINUS It is a transverse recess behind theascending aorta and pulmonary think and in front of s.v.eand sup pulmonary.veins.DIPANYARRAYBOUNDARY - AnteriorlyAscending acrta and Pulmonory trunkPosteriorlySuperior Vena CavaInferiorlyLeft atriumOn Each SideOpens into generalIt develops from degeneration of the part of dorsal mesocandiumpericandial cavity,2OBLIQUE SINUS It is a recess of serous pericardium behind thebase of the heart (actually left atrium). It is enclosed by J-shapedsheath of visceral layer of pericardium enclosing 6 veinsBOUNDARY- AnteriorlyLeft atrium.PosteriorlyOn the Right SideParieral pericardium and Oesophagus.right By reflection of visceral pericardium along thepulmonary veins and I.V.eOn the left Side:By the reflection of visceral pericardium alongSuperiorlyleft pulmonary veins.Inferiorlyright superior pulmonary veinsBy reflection and left of visceral pericardium along theIt is open into the rest of pericardial cavity. PERICARDIUMCONTENTS OF PERICARDIUMThe following are the contents of the pericardium-1Heart with cardiac vessels and nerves.2Ascending Aorta3Pulmonary Trunk.4Lower half of Superior Vena Cara5Inferior vena cara (Terminal part)6Terminal pants of Pulmonary veins,ARTERIAL SUPPLYJEROUS(A) PERICARDIUM (Parietal layer)FIBROUS PERICARDIUM and VISCERALSupplied by the branches of the following arteries -(1) Internal Thoracic Artery (2) Musculophrenic arteries(3) Descending thoracic aorta(B) SEROUS PERICARDIUM (Visceral layer)Supplied by the 1 Poromary arteriesNERVE SUPPLYDIPANIMAR RAYFIBROUS PERICARDIUM + SEROUS PERI CARDUM (Parietal layer)Supplied to by Phrenic nerves (Somatic Nerve fibres) They are sensitivepainSEROUS PERICARDIUM (VISCERAL LAYER)Supplied by the branches of sympathetic trunks andvagus nerves (Autonomic Nerre fibres) This layer is insensitiveto pain.UPain alone. of pericarditis originates in the parietal pericardiumdCardiac pain or Angina originales in the cardiac muscleor in the vessels of the heart.