Heart

Functions of the heart 

• Right side of the heart, pumps blood through the pulmonary circulation
•  Carries blood to the lungs, CO2 diffuse from the blood into the lungs and O2 diffuse from the lungs into the blood. 
• Pulmonary circulation returns the blood to the left side of the heart 
• Left side of the heart then pumps blood through the systemic circulatio, which delivers 02 and nutrients to all the remaining tissue of the body. 
• From these tissues, C02 and other waste products are carried back to the right side of the heart. 

Size, shape and location of the heart 

• Important to know the location of the heart in the thoriac cavity 
• A stethoscope to hear the heart sound ans positioning electrodes to record an electrocardiogram from the chest leads depend on this knowledge 
• Effective cardiopulmonary resculation also depends on a reasonable knowledge of the position of the heart. 

Pericardium 

• The percidium is a doubled layer, closed sac that surrounds the heart. 
• Outer fibrous pericium and serous perdicium. 
• Fibrious is a tough, fibrous connective tissue layer that prevents overdistensions of the heart and anchors it with mediastinum. 
• The fibrous pericardium is connectivetissue coverings of the great vessels, such as the arota and inferiorly is attached to the surface of the diaphragm. 
• The serous peciardium is a layer of simple aquamous epitherlium. 

Heart wall

• Heart wall is composed of three layers, epicardium, myocardium and endocardium. 

External anatomy and coronary circulation 

• The cornoray circulation consists of blood vessels that carry blood to and from the tissues of the heart wall.
• Major vessels of the coronary circulation lie in several groovesm or sulci on the surface of the heart. 

Right and left atria 

• Right atria has three major openings 1) opening from the superior vena cana, 2) opening from the inferior cava, 3) opening from the coronary sinus
• Openings from the superior vena cava and the inferior vena cava receive blood from the body, and the opening of the conary sinus receives blood from the heart itself
• Left atrium has four relitavely uniform openings from the four pulmonary veins that receive blood from us 
• Right and left atria are seperated from each other by the wall of tissues called the intertial septum 
• Fossa ovalis is slight, oval depression on the right side of the intertrial septum marking the former location of the foramen ovale, an opening between the right and left atria in the embryonic and fetal heart. 
• Fetal heart, opening allows blood to flow from the right to the left atriuum and bipass the pulmonary circulation. 

Right and left ventricles 

• Atria open into ventricles through antrovencular canals 
• Each ventricle has one largem superioly placed outflow route near the midline of the heart
• Blood flow from the right ventricle into the pulmonary trunk 
• Blood flows from the left ventricle to the aorta
• The two ventcicles are seperated from each other by interventicular septum, which has a thick, muscular part towards the apex and a thin membrous part of the atria 
• Walls of the left…