Anatomy and Histology of CVS (The Heart) PDF

Anatomy and Histology of CVS (The Heart) Practical 7 Location In the mediastinum, between second rib and fifth intercostal space On the superior surface of diaphragm Two-thirds to the left of the midsternal line Anterior to the vertebral column, posterior to the sternum...

Anatomy and Histology of CVS (The Heart) Practical 7 Location In the mediastinum, between second rib and fifth intercostal space On the superior surface of diaphragm Two-thirds to the left of the midsternal line Anterior to the vertebral column, posterior to the sternum Midsternal line 2nd rib Sternum Diaphragm Point of maximal intensity (PMI) (a)  Approximately the size of a fist Great veins and arteries at the base Pointed tip is apex Surrounded by pericardial sac Base of heart Cut edge of Wrist (corresponds parietal pericardium to base of heart) Inner wall (corresponds Fibrous tissue of to epicardium) pericardial sac Parietal pericardium Air space (corresponds to pericardial cavity) Areolar tissue Mesothelium Outer wall (corresponds to parietal pericardium) Cut edge of epicardium Fibrous Balloon attachment to diaphragm Apex of heart The relationship between the heart and the pericardial cavity; compare with the fist-and-balloon example. Pericardial Sac The clear tissue being Lifted up by the scalpel Is the pericardium Superior Aorta vena cava Parietal pleura (cut) Pulmonary Left lung trunk Pericardium (cut) Apex of Diaphragm heart (c) Figure 18.1c  The Heart Wall Parietal pericardium Dense fibrous layer Areolar tissue Mesothelium Pericardial cavity Myocardium (cardiac muscle tissue) Cardiac muscle cells Epicardium (outer layer) (visceral pericardium) Connective tissues Mesothelium Areolar tissue Endocardium (inner layer) Areolar tissue Endothelium  Characteristics of Cardiac Muscle forms most of heart wall (myocardium) involuntary (unconscious) autorhythmicity (contracts without external stimuli) fast contraction, non-fatigable constant rhythm may be modified by neural and hormonal signals  Cardiac Muscle Tissue striated unicellular uninucleate branched cells intercalated discs  OVERVIEW OF THE CARDIOVASCULAR SYSTEM Pulmonary circuit Systemic circuit Arteries (Including the coronary arteries) Veins (Including the coronary veins) Capillaries (Arterioles & Venules) Four chambers of the heart  Pathway of blood: Heart and Lungs The Pulmonary Circuit Carries blood to and from gas exchange surfaces of lungs The Systemic Circuit Carries blood to and from the body Blood alternates between pulmonary circuit and systemic circuit  Three Types of Blood Vessels 1. Arteries – Carry blood away from heart 2. Veins – Carry blood to heart 3. Capillaries – Networks between arteries and veins  Four Chambers of the Heart 1. Right atrium Collects blood (O2 -poor) from systemic circuit 2. Right ventricle Pumps blood (O2 -poor) to pulmonary circuit 3. Left atrium Collects blood (O2 -rich) from pulmonary circuit 4. Left ventricle Pumps blood (O2 -rich) to systemic circuit Flow of blood through the pulmonary and systemic circuits, and the heart  Atria of the Heart Atria are the receiving chambers of the heart Each atrium has a protruding auricle (expandable extension of an atrium) and when not filled with blood, outer portion of atria deflates and becomes lumpy, wrinkled flap  Left common Left subclavian artery carotid artery Arch of aorta Brachiocephalic Ligamentum trunk arteriosum Descending aorta Ascending aorta Left pulmonary artery Superior vena cava Pulmonary trunk Auricle of right Auricle of RIGHT left atrium atrium ATRIUM Fat and vessels RIGHT in anterior VENTRICLE interventricular sulcus Fat and vessels in LEFT coronary VENTRICLE sulcus Major anatomical features on the anterior surface.  Surface Anatomy of the Heart Left common Left subclavian artery carotid artery Aortic arch Ligamentum Left pulmonary artery Brachiocephalic Right pulmonary arteriosum trunk Aortic arch Left pulmonary veins artery Descending Fat and vessels Superior Ascending aorta in coronary Left vena cava aorta Left pulmonary sulcus atrium artery Superior Coronary Pulmonary Right vena cava trunk sinus pulmonary Auricle Auricle of veins of right Right left atrium Right (superior atrium atrium Left atrium and inferior) ventricle Fat and vessels in anterior Right Inferior Right ventricle interventricular ventricle vena cava Fat and Left sulcus ventricle vessels in coronary Fat and vessels in sulcus posterior interventricular sulcus c Major landmarks on the posterior surface. Coronary a arteries (which supply the heart itself) are shown in Major anatomical features on the anterior surface. red; coronary veins are shown in blue. © 2017 Pearson Education, Ltd.  Left common carotid artery Left subclavian artery Brachiocephalic Ligamentum arteriosum trunk Pulmonary trunk Superior Aortic arch vena cava Pulmonary valve Right pulmonary Left pulmonary arteries arteries Ascending aorta Left pulmonary Fossa ovalis LEFT veins Opening of ATRIUM Interatrial septum coronary sinus Aortic valve RIGHT ATRIUM Pectinate muscles Cusp of left AV (mitral) valve Conus arteriosus LEFT VENTRICLE Cusp of right AV (tricuspid) valve Chordae tendineae Interventricular septum Papillary muscles Trabeculae RIGHT VENTRICLE carneae Inferior vena cava Moderator band Pectinate muscles mark atrial walls Descending aorta Blood enters right atria from superior and inferior venae cavae and coronary sinus Blood enters left atria from pulmonary veins (left and right)  Ventricles of the Heart Ventricles are the discharging chambers of the heart  Left common carotid artery Left subclavian artery Brachiocephalic Ligamentum arteriosum trunk Superior Pulmonary trunk Aortic arch vena cava Pulmonary valve Right pulmonary Left pulmonary arteries arteries Ascending aorta Left pulmonary Fossa ovalis veins LEFT ATRIUM Opening of Interatrial septum coronary sinus Aortic valve RIGHT ATRIUM Pectinate muscles Cusp of left AV (mitral) valve Conus arteriosus LEFT VENTRICLE Cusp of right AV (tricuspid) valve Chordae tendineae Interventricular septum Papillary muscles RIGHT VENTRICLE Trabeculae Inferior vena cava carneae Moderator band Descending aorta Papillary and trabeculae carneae muscles mark ventricular walls Right ventricle pumps blood into the pulmonary trunk Left ventricle pumps blood into the aorta Without most of pericardial layers 23  Fibrous Pulmonary Auricle of Ascending pericardium trunk left atrium aorta Parietal pericardium Superior vena cava Auricle of right atrium RIGHT ATRIUM Right coronary artery Coronary sulcus RIGHT VENTRICLE Marginal branch of right coronary artery Parietal pericardium Anterior LEFT fused to diaphragm interventricular VENTRICLE sulcus Major anatomical features on the anterior surface.  Heart Valves Heart valves ensure unidirectional blood flow through the heart Atrioventricular (AV) valves lie between the atria and the ventricles – Right AV = Tricuspid (3) valve – Left AV = Bicuspid (2)/mitral valve – AV valves prevent backflow into the atria when ventricles contract – Chordae tendineae anchor AV valves to papillary muscles Figure 20-6c The Sectional Anatomy of the Heart. Left subclavian artery Left common carotid artery Brachiocephalic trunk Superior vena cava Pulmonary Ascending aorta trunk Cusp of pulmonary valve Auricle of left atrium Right atrium Cusp of left AV (bicuspid) valve Chordae tendineae Papillary muscles Cusps of right AV (tricuspid) valve Left ventricle Trabeculae carneae Interventricular Right ventricle septum c Anterior view of a frontally sectioned heart showing internal features and valves.  Figure 20-6b The Sectional Anatomy of the Heart Chordae tendineae Papillary muscles The papillary muscles and chordae tendinae supporting the right AV (tricuspid) valve. The photograph was taken from inside the right ventricle, looking toward a light shining from the right atrium.  Figure 20-6c The Sectional Anatomy of the Heart Ascending aorta Left coronary artery branches (red) Cusp of aortic valve and great cardiac vein (blue) Inferior vena cava Fossa ovalis Cusp of left AV (bicuspid) valve Pectinate muscles Chordae tendineae Coronary sinus RIGHT ATRIUM Papillary muscles Cusps of right AV (tricuspid) valve LEFT VENTRICLE Interventricular Trabeculae carneae septum RIGHT VENTRICLE A frontal section, anterior view.  Aortic semilunar valve lies between the left ventricle and the aorta Pulmonary semilunar valve lies between the right ventricle and pulmonary trunk Semilunar valves prevent backflow of blood into the ventricles (Semilunar = half-moon-shaped) 30  Anterior interventricular artery supplies small tributaries continuous with those of the posterior interventricular arteries – such interconnections between arteries are known as arterial anastomoses – Therefore the blood supply to cardiac muscle remains relatively constant despite pressure fluctuations http://www.mananatomy.com/basic-anatomy/anastomosis-types Aorta- --------------..,...-,..--------Superior vena cava Left--------------, -------Right pulmonary artery pulmonary artery Left ---------=-- IL-­ pulmonary veins 1-"""""..,._-----Right pulmonary veins Auricle---------- of left atrium Left atrium ---------ffipij; ¼-----Inferior vena cava.:,-,!!'------Right coronary Posterior vein------ ----t -::;> /, artery (in right of left ventricle atrioventricular groove) "------Coronary sinus..______ Posterior interventricular artery Left ventricle ------- (in posterior interventricular s Apex-----------i: ---...____ Middle cardiac v, (di --- ------Right ventricle Heart:Frontal Section