Heart Anatomy PDF

PowerPoint® Lecture Slides prepared by Vince Austin, University of Kentucky The Cardiovascular System: The Heart Part A...

PowerPoint® Lecture Slides prepared by Vince Austin, University of Kentucky The Cardiovascular System: The Heart Part A 18 Human Anatomy & Physiology, Sixth Edition Elaine N. Marieb Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  Heart Anatomy ▪ Approximately the size of your fist ▪ Location ▪ Superior surface of diaphragm ▪ Left of the midline ▪ Anterior to the vertebral column, posterior to the sternum Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  Heart Anatomy Figure 18.1 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  Coverings of the Heart: Anatomy ▪ 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 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  Coverings of the Heart: Physiology ▪ The pericardium: ▪ Protects and anchors the heart ▪ Prevents overfilling of the heart with blood ▪ Allows for the heart to work in a relatively friction- free environment Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  Pericardial Layers of the Heart Figure 18.2 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  Heart Wall ▪ Epicardium – visceral layer of the serous pericardium ▪ Myocardium – cardiac muscle layer forming the bulk of the heart ▪ Endocardium – endothelial layer of the inner myocardial surface Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  External Heart: Major Vessels of the Heart (Anterior View) ▪ Vessels returning blood to the heart include: ▪ Superior and inferior venae cavae ▪ Right and left pulmonary veins ▪ Vessels conveying blood away from the heart include: ▪ Pulmonary trunk, which splits into right and left pulmonary arteries ▪ Ascending aorta (three branches) – brachiocephalic, left common carotid, and subclavian arteries Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  External Heart: Anterior View Figure 18.4b Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  External Heart: Posterior View Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 18.4d  Gross Anatomy of Heart: Frontal Section Figure 18.4e Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  Atria of the Heart ▪ Atria are the receiving chambers of the heart ▪ Each atrium has a protruding auricle ▪ Pectinate muscles mark atrial walls ▪ Blood enters right atria from superior and inferior venae cavae and coronary sinus ▪ Blood enters left atria from pulmonary veins Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  Ventricles of the Heart ▪ Ventricles are the discharging chambers of the heart ▪ Papillary muscles and trabeculae carneae muscles mark ventricular walls ▪ Right ventricle pumps blood into the pulmonary trunk ▪ Left ventricle pumps blood into the aorta Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  Pathway of Blood Through the Heart and Lungs ▪ Right atrium → tricuspid valve → right ventricle ▪ Right ventricle → pulmonary semilunar valve → pulmonary arteries → lungs ▪ Lungs → pulmonary veins → left atrium ▪ Left atrium → bicuspid valve → left ventricle ▪ Left ventricle → aortic semilunar valve → aorta ▪ Aorta → systemic circulation Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  Pathway of Blood Through the Heart and Lungs Figure 18.5 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  Heart Valves ▪ Heart valves ensure unidirectional blood flow through the heart ▪ Atrioventricular (AV) valves lie between the atria and the ventricles ▪ AV valves prevent backflow into the atria when ventricles contract ▪ Chordae tendineae anchor AV valves to papillary muscles Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  Heart Valves ▪ 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 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  Heart Valves Figure 18.8a, b Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  Heart Valves Figure 18.8c, d Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  Atrioventricular Valve Function Figure 18.9 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  Semilunar Valve Function Figure 18.10 Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings  Microscopic Anatomy of Heart Muscle Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 18.11