Anatomy of the Heart

1. THE HEART Lecture on Anatomy of the Heart ( [email protected])

2. Lecture on Anatomy of the Heart ( [email protected]) 3. POSITION Lies within the pericardium in middle mediastinum Behind the body of sternum and the 2nd to 6th costal cartilages In front of the 5th to 8th thoracic vertebrae A third of it lies to the right of median plane and 2/3 to the left Anterior to the vertebral column, posterior to the sternumLecture on Anatomy of the Heart ( [email protected]) 4. HEART ANATOMYLecture on Anatomy of the Heart ( [email protected]) 5. EXTERNAL CHARACTERISTICSA hollow muscular organ, pyramidal in shape , somewhat larger than a closed fist; consists of four chambers (right and left atria, right and left ventricles)Cardiac Apex is formed by left ventricle and is directed downwards and forwards to the left. It lies at the level of the fifth left intercostal space, 1~2cm medial to the left midclavicular line (9cm from the midline)Lecture on Anatomy of the Heart ( [email protected]) 6. EXTERNAL CHARACTERISTICS The apex beat point of maximum impulse (PMI), is the furthermost point outwards (laterally) and downwards (inferiorly) from the sternum at which the cardiac impulse can be felt. Lateral and/or inferior displacement of the apex beat usually indicates enlargement of the heart, called cardiomegaly Approximately the size of your fist Wt. = 250-300 grams Cardiac base is formed by the left atrium and to a small extent by the right atrium. It faces backward, upward and to the right Lecture on Anatomy of the Heart ( [email protected]) 7. Two surfaces Sternocostal surface is formed mainly by the right atrium and right ventricle, and a lesser portion of its left is formed by the left auricle and ventricle. It is directed forwards and upwards Diaphragmatic surface is formed by the ventricles chiefly the left ventricle, directed backwards and downwards, and rests upon the central tendon of the diaphragm Three borders Right bordervertical, is formed entirely by right atrium Left borderround, is mainly formed by the left ventricle and partly by the left auricle Inferior borderhorizontal, is formed by the right ventricle and cardiac apex Lecture on Anatomy of the Heart ( [email protected]) 8. Four grooves Coronary sulcus (circular sulcus) which marks the division between atria and ventricles, contains the trunks of the coronary vessels and completely encircles the heart Interatrial groove separates the two atria and is hidden by pulmonary trunk and aorta in front Interventricular grooves anterior and posterior, mark the division between ventricles (which separates the RV from the LV), the two grooves extend from the base of the ventricular portion to a notch called: the cardiac apical incisureLecture on Anatomy of the Heart ( [email protected]) 9. COVERING OF THE HEART Pericardium a double-walled sac around the heart Composed of: A superficial fibrous pericardium A deep two-layer serous pericardium The parietal layer lines the internal surface of the fibrous pericardium The visceral layer or epicardium lines the surface of the heart They are separated by the fluid-filled pericardial cavity called the pericardial cavity Protects and anchors the heart Prevents overfilling of the heart with blood Allows for the heart to work in a relatively friction-free environment Lecture on Anatomy of the Heart ( [email protected]) 10. Interatrial septum Located between right and left atria Contains fossa ovalis Interventricular septum Located between right and left ventricles upper membranous part thick lower muscular partLecture on Anatomy of the Heart ( [email protected]) 11. Lecture on Anatomy of the Heart ( [email protected]) 12. PERICARDIAL LAYERLecture on Anatomy of the Heart ( [email protected]) 13. LAYERS OF THE HEART WALLEpicardium visceral pericardium Myocardium cardiac muscle layer forming the bulk of the heart Endocardium endothelial layer of the inner myocardial surfaceLecture on Anatomy of the Heart ( [email protected]) 14. XRAYLVH Left ventricular hypertrophy Lecture on Anatomy of the Heart ( [email protected]) NORMAL 15. FRONTAL SECTIONLecture on Anatomy of the Heart ( [email protected]) 16. ATRIA OF THE HEART Atria - receiving chambers of the heart Receive venous blood returning to heart Separated by an interatrial septum (wall) Foramen ovale - opening in interatrial septum in fetus Fossa ovalis - remnant of foramen ovale Each atrium has a protruding auricle Pectinate muscles mark atrial walls Pump blood into ventricles Blood enters right atria from superior and inferior venae cavae and coronary sinus Blood enters left atria from pulmonary veins Lecture on Anatomy of the Heart ( [email protected]) 17. Left auricleprojecting to the right, pectinate muscles in wall Four inletsfour orifices of pulmonary veins open through the posterior wall One outletleft atrioventricular orifice, blood leaves through left atrioventricular orifice to left ventricle Lecture on Anatomy of the Heart ( [email protected]) 18. VENTRICLE OF THE HEART Ventricles are the discharging chambers of the heart Papillary muscles and trabeculae carneae muscles mark ventricular walls Separated by an interventricular septum Contains components of the conduction system Right ventricle pumps blood into the pulmonary trunk Left ventricle pumps blood into the aorta Thicker myocardium due to greater work load Pulmonary circulation supplied by right ventricle is a much low pressure system requiring less energy output by ventricle Systemic circulation supplied by left ventricle is a higher pressure system and thus requires more forceful contractions Lecture on Anatomy of the Heart ( [email protected]) 19. Lecture on Anatomy of the Heart ( [email protected]) 20. Left ventricle Its wall is three times thicker than that of right ventricle One inletleft atrioventricular orifice One outletaortic orifice Two partsdivided by anterior cusps of mitral valve Inflow tractrough walls Outflow tract aortic vestibule smooth area leading to aortic orifice Lecture on Anatomy of the Heart ( [email protected]) 21. SEPTUMS/FIBROUS SKELETON Interatrial septum Located between right and left atria Contains fossa ovalis Interventricular septum Located between right and left ventricles upper membranous part thick lower muscular part Fibrous skeleton Fibrous rings that surround the atrioventricular, pulmonary, and aortic orifices Left and right fibrous trigons Lecture on Anatomy of the Heart ( [email protected]) 22. ANTERIOR VIEWLecture on Anatomy of the Heart ( [email protected]) 23. HEART VALVES Heart valves ensure unidirectional blood flow through the heart Composed of an endocardium with a connective tissue core Two major types Atrioventricular valves Semilunar valves Atrioventricular (AV) valves lie between the atria and the ventricles R-AV valve = tricuspid valve L-AV valve = bicuspid or mitral valve AV valves prevent backflow of blood into the atria when ventricles contract Chordae tendineae anchor AV valves to papillary muscles of ventricle wall Prevent prolapse of valve back into atrium Lecture on Anatomy of the Heart ( [email protected]) 24. SEMILUNAR HEART VALVES Semilunar valves prevent backflow of blood into the ventricles Have no chordae tendinae attachments Aortic semilunar valve lies between the left ventricle and the aorta Pulmonary semilunar valve lies between the right ventricle and pulmonary trunk Heart sounds (lub-dup) due to valves closing Lub - closing of atrioventricular valves Dub- closing of semilunar valves Lecture on Anatomy of the Heart ( [email protected]) 25. Tricuspid valve Guards right atrioventricular orifice Three triangular cusps: anterior, posterior and septal, the base of cusps are attached to fibrous ring surrounding the atrioventricular orifice Chordae tendineae fine, white, connective tissue cords, attach margin of cusps to papillary muscles Mitral valve Guards left atrioventricular orifice Two triangular cuspsanterior and posterior with Similar structures to those of rightLecture on Anatomy of the Heart ( [email protected]) 26. Valve of pulmonary trunk Guards the orifice of pulmonary trunk Has three semilunar cusps each with free borderLecture on Anatomy of the Heart ( [email protected]) 27. POSTERIOR VIEWLecture on Anatomy of the Heart ( [email protected]) 28. Lecture on Anatomy of the Heart ( [email protected]) 29. CONDUCTING SYSTEM OF THE HEART Cardiac muscle tissue has intrinsic ability to: Generate and conduct impulses Signal these cells to contract rhythmically Conducting system A series of specialized cardiac muscle cells Sinoatrial (SA) node sets the inherent rate of contraction Lecture on Anatomy of the Heart ( [email protected]) 30. CONDUCTING SYSTEM OF THE HEARTLecture on Anatomy of the Heart ( [email protected]) 31. INNERVATION Heart rate is altered by external controls Nerves to the heart include: Visceral sensory fibers Parasympathetic branches of the vagus nerve Sympathetic fibers from cervical and upper thoracic chain gangliaLecture on Anatomy of the Heart ( [email protected]) 32. Sinuatrial node (SA node) Called the pacemaker cell (P cell) Located at the junction of right atrium and superior vena cava, upper part of the sulcus terminalis, under the epicardiumLecture on Anatomy of the Heart ( [email protected]) 33. Atrioventricular node (AV node) Located in the lower part of interatrial septum just above the orifice of coronary sinus, under the endocardium Lower part related to membranous part of interventricular septum Atrioventricular bundle (AV bundle) Passes forward through right fibrous trigon to reach inferior border of membranous part Divides into right and left branches at upper border of muscular part of interventricular septumLecture on Anatomy of the Heart ( [email protected]) 34. MAJOR VESSELS OF THE HEART Vessels returning blood to the heart include: Superior and inferior venae cavae Open into the right atrium Return deoxygenated blood from body cells Coronary sinus Opens into the right atrium Returns deoxygenated blood from heart muscle (coronary veins) Right and left pulmonary veins Open into the left atrium Return oxygenated blood from lungs Lecture on Anatomy of the Heart ( [email protected]) 35. MAJOR VESSELS OF THE HEART Vessels conveying blood away from the heart include: Pulmonary trunk Carries deoxygenated blood from right ventricle to lungs Splits into right and left pulmonary arteries Ascending aorta Carries oxygenated blood away from left atrium to body organs Three major branches Brachiocephalic Left common carotid, Left subclavian artery Lecture on Anatomy of the Heart ( [email protected]) 36. BLOOD FLOW THROUGH THE HEARTLecture on Anatomy of the Heart ( [email protected]) 37. PATHWAY OF BLOOD THROUGH THE HEARTLecture on Anatomy of the Heart ( [email protected]) 38. DISORDERS OF THE HEARTCoronary artery disease Atherosclerosis fatty deposits Arteriosclerosis - hardening of the arteries Angina pectoris chest pain Myocardial infarction blocked coronary artery Silent ischemia no pain or warning Fibrillation - irregular heart beat; may occur in either atria or ventricles Lecture on Anatomy of the Heart ( [email protected]) 39. Lecture on Anatomy of the Heart ( [email protected]) 40. THANK YOUName: Samuel Nnamani Phone: 13257081442 QQ : 1541665378 Lecture on Anatomy of the Heart ( [email protected])

Anatomy of the Heart

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Transcript of Anatomy of the Heart