Completed notes of the course Part 3

Pagina 1

TECHNOLOGIES FOR REGENERATIVE MEDICINE 3 The cardiovascular system is composed by: heart, arteries, veins and capillaries; it is divided into systemic circulation (general or big) and pulmonary circulation (small). The heart is situated in the anterior mediastinum, it is enveloped by the pericardium and it has a weight of 250-300 g for women and 300-350 g for men. It is divided in four chambers which are the right atrium, the right ventricle, the left atrium and the left ventricle. The adult heart is formed by the coronary arteries, the heart valves, the electrical conducting system and the myocardium. In the heart there are four valves: the tricuspid valve that separates the right atrium and the right ventricle, the pulmonary semilunar valve that separates the right ventricle and the pulmonary arteria, the mitral bicuspid valve that separates the left atrium and the left ventricle, and the aortic semilunar valve that separates the left ventricle and the aorta. The arteries that perfuse the heart are the coronary arteries, they are differentiated in branches which are the left coronary artery and the right coronary artery, and in the circulation area composed by epicardial and microvascular. The fibrous skeleton of the heart is a high density single structure of connective tissue that forms and anchors the valves. It is composed by four rings (left fibrous ring, right fibrous ring, pulmonary ring and aortic ring), two trigones, a membranous part and a tendinous band. The fibrous skeleton’s functions are: anchoring the structure, keeps the valves open, bundle insertion and separation, and electrical insulator. The electrical conduction of the heart is possible due the specific myocardium, especially in the sinoatrial node and the atrioventricular node, and in the bundle…