Heart Anatomy PDF

 Structures of the Heart 1. fibrous cardiac skeleton tricuspid anulus mitral anulus Four annuli pulmonary valve anulus aortic valve anulus...

 Structures of the Heart 1. fibrous cardiac skeleton tricuspid anulus mitral anulus Four annuli pulmonary valve anulus aortic valve anulus pulmonary valve anulus aortic valve anulus tricuspid mitral anulus anulus  right fibrous trigone (central fibrous body) : between the tricuspid annulus, the mitral annulus and the fibrous Two trigones ring of the aortic valve left fibrous trigone: between the mitral annulus and the fibrous ring of the aortic valve left fibrous trigone right fibrous trigone (central fibrous body) 2. Wall of the heart Endocardium: valves Myocardium: atrial and ventricular muscle fibers Epicardium: visceral layer of serous pericardium 3. interatrial and interventricular septa interatrial Interatrial septum septum - made up of the endocardium, the connective tissue and a few myocardial fibers - oval fossa is the thinnest site - atrial septal defects Interventricular septum septal leaflet of tricuspid valve membranous right part atrium right muscular part ventricle left ventricle 3. interatrial and interventricular septa Interatrial septum Interventricular septum atrioventricular part membranous part interventricular part muscular part Ventricular septal defects usually involve the membranous part of the interventricular septum septal leaflet of tricuspid valve membranous right part atrium right muscular part ventricle left ventricle  Cardiac Conduction System sinuatrial node Function: initiating and conducting the action potentials Composition：highly specialized autorhythmic myocardial cells and conducting fibers Sinuatrial node Internodal tracts Atrioventricular node Atrioventricular bundle (His bundle) Bundle branches Purkinje fibers  Sinoatrial node (SA node): - located in the subepicardial region at the junction of the superior vena cava and right atrium near the upper end of the terminal sulcus. - the pacemaker of the heart (initiates muscle contraction and determines the heart rate) - transmits impulses to both atria and to the atrioventricular node  Atrioventricular node (AV node): - a flat elliptical structure - subendocardial, situated directly in the triangle of Koch - stimulated by the SA node and transmits impulses to the AV bundle  Internodal tracts: - physiological pathways, - including anterior, middle and posterior tracts - connected the sinuatrial node with the atrioventricular node sinuatrial node  sinuatrial node Atrioventricular bundle (His bundle): - arises from cells of the atrioventricular node - transmits impulses to the walls of the ventricles - runs through the right fibrous trigone to the interventricular septum - divides into right and left bundle branches Bundle branches: The right bundle branch: originates from the His bundle near the membranous septum and courses along the septomarginal trabecula, passing toward the base of the anterior papillary muscle. The left bundle branch: further subdivides into several smaller branches that begin at the ventricular septal surface and radiate around the left ventricle. sinuatrial node  Purkinje fibers: connected with the ends of the fascicles of the left and right bundle branches to form the subendocardial networks. sinuatrial node  Coronary circulation 1. Coronary arteries posterior interventricular branch ③ (posterior descending artery, PDA) Right coronary artery ① right marginal branch ④ sinoatrial nodal branch ⑤(about 60% of the population) atrioventricular nodal branch to supply the right atrium and ventricle, part of the diaphragmatic wall of the left ventricle, posterior one-third of the interventricular septum, and part of conduction system (including atrioventricular node, sinoatrial node and posterior part of the left bundle branch). ⑤ ⑤ ⑦ ② ① ⑥ ③ ④  anterior interventricular branch ⑥ (left anterior descending artery, LAD) Left coronary artery ② circumflex branch ⑦ sinoatrial nodal branch (about 40% of the population) to supply the left atrium and ventricle, the adjacent part of the right ventricle, the anterior two-thirds of the interventricular septum and part of the conduction system (including right bundle branch, anterior part of the left bundle branch and sinoatrial node). ⑤ ⑤ ⑦ ② ① ⑥ ③ ④ Distribution of the coronary arteries Anterior and posterior views of the heart, with superior views of transverse sections through the ventricles “Distribution”: the area of the myocardium supplied by each artery as seen in the transverse views “Dominance”: the artery that gives rise to the posterior interventricular artery as seen in the anterior and posterior views Green: right coronary artery and branches Red: left coronary artery and branches Coronary Angiography  2. Cardiac veins Great cardiac vein Coronary Right Middle cardiac vein sinus atrium Small cardiac vein Anterior cardiac veins Smallest cardiac veins Chambers of Heart Anterior cardiac v. Great cardiac v. Coronary sinus Small cardiac v. Middle cardiac v.  The Pericardium 1. Composition outer layer: fibrous pericardium parietal layer inner layer: serous pericardium pericardial cavity visceral layer (epicardium) Pericardial cavity: the slight space created between the two layers of serous pericardium, containing a small amount of fluid. fibrous pericardium epicardium visceral layer parietal layer serous pericardium Bare area of pericardium: uncovered with the lung and pleura, behind the lower part of the sternum and the left 4th-6th costal cartilages Intracardiac injection: to give the drug directly into the heart muscles or ventricles Pericardiocentesis: to drain fluid from the pericardial sac via aspiration 2. Sinuses of pericardium The transverse pericardial sinus: a passage between the inflow channels and the outflow channels of the heart superior vena cava inflow channels pulmonary veins aorta outflow channels pulmonary trunk transverse sinus A finger placed in the transverse sinus separates arteries from veins.  The oblique pericardial sinus: a recess of the pericardial cavity posterior to the heart between the right and left pulmonary veins. oblique sinus A hand placed under the apex of the heart and moved superiorly slips into the oblique sinus.  The anteroinferior pericardial sinus: lied the anteroinferior part of the pericardial cavity and formed by the reflexion of the anterior wall into the inferior wall of the parietal layer of serous pericardium. Pericardial effusion: the excessive pericardial fluid accumulated in the sinus, it is the site for removing the fluid with a needle. anteroinferior sinus  Practice I Shape: cardiac apex, cardiac base, sternocostal surface, diaphragmatic surface, right border, left border, inferior border, coronary sulcus, anterior interventricular groove, posterior interventricular groove, interatrial groove, atrioventricular crux, cardiac apical incisure Right atrium: terminal groove, terminal crest, pectinate muscle, right auricle, right atrioventricular orifice, orifice of superior vena cava, orifice of inferior vena cava, orifice of coronary sinus, oval fossa, triangle of Koch Right ventricle: supraventricular crest, trabeculae carneae, septomarginal trabecula, papillary muscle, tricuspid valve, chordae tendineae, orifice of pulmonary trunk, pulmonary valve, nodule of semilunar valve, pulmonary sinus  Practice II Left atrium: left auricle, left atrioventricular orifice, orifice of pulmonary vein Left ventricle: mitral valve, chordae tendineae, papillary muscles, aortic orifice, aortic valve, nodule of semilunar valve, aortic sinus, orifices of coronary artery Skeleton: tricuspid annulus, mitral annulus, pulmonary valve annulus, aortic valve annulus, right fibrous trigone, left fibrous trigone, epicardium, myocardium, endocardium, interatrial septum, interventricular septum Blood vessels: right coronary artery, posterior interventricular branch, right marginal branch, left coronary artery, anterior interventricular branch, circumflex branch, coronary sinus, great cardiac vein, middle cardiac vein, small cardiac vein. Pericardium: fibrous pericardium, serous pericardium (parietal layer and visceral layer), pericardial cavity, transverse sinus, oblique sinus, anteroinferior sinus Drawing Homework: Chambers of the heart (with labeling) Notice: Your homework is regarded as a part of your final mark, so please hand in your homework before final examination !!!  Highlights 1. Composition of the cardiovascular system. 2. Pulmonary circulation and systemic circulation 3. External features of the heart 4. Important structure in the four chambers of the heart (e.g., tricuspid complex, mitral complex, pulmonary valve, and aortic valve) 5. Right fibrous trigone and left fibrous trigone 6. Composition of the interventricular septum 7. Composition of the conduction system of heart 8. Left and right coronary arteries and their main branches 9. Coronary sinus and its tributaries 10. Composition of the pericardium and sinuses of the pericardium