Cardiovascular system overview

Cardiovascular system overview Cardiovascular system consists of the heart and blood vessels. The blood vessels supplying various organ systems can be considered as regional circulation. For example, blood vessels supplying the brain constitute the cerebral circulation while those supplying the kidneys form the renal circulation. The heart has four chambers and four valves regulating flow between the chambers and the great vessels. The four chambers are the right and left atria, the upper thin walled chambers; the thick walled lower chambers being the right and left ventricles. Though both ventricles are of equal thickness before birth, the left ventricle is the dominant ventricle in the adult. The tricuspid valve prevents backflow of blood from the right ventricle when it contracts. It is the largest of the four valves and has three leaflets – septal, anterior and posterior. Mitral valve guards the orifice between the left atrium and left ventricle. It has an anterior and a posterior leaflet. The valve resembles the headgear of the bishop (mitre or miter) and hence the name. The pulmonary valve prevents backflow of blood from the pulmonary artery into the right ventricle in diastole. Similarly, the aortic valve prevents backflow from aorta to the left ventricle. These valves are called semilunar valves because they have semilunar cusps, three each. Deoxygenated blood returning from the body is received in the right atrium from the superior and inferior vena cava and passes...
Source: Cardiophile MD - Category: Cardiology Authors: Tags: HBC Source Type: blogs