preview

Heart Pathophysiology

Decent Essays

The function of the heart is to pump blood around the body. It is a hollow muscle and can be found between the lungs in the mediastinum and behind the sternum and between the second and sixth ribs. It is the size of a fist and has four chambers. The upper chambers are the left and right atria, with the bottom chambers the left and right ventricles. The heart consists of several layers: the pericardium (outer protective covering of fibrous tissue), the epicardium (made up of epithelial cells and secretes serum which prevents the layers rubbing), the myocardium (the muscular wall of the heart and forms a septum which separates the right and left side of the heart.
The septum also contains the sino-atrial atrioventricular nodes, which is a type …show more content…

There are four valves in the heart that stop the blood from flowing in the wrong direction.
These are the tricuspid, pulmonary, mitral and aortic valves. The SA node (sino-atrial node) stimulates the atrium to contract forcing blood through the valves to the ventricles. The AV
(atrioventricular) node then stimulates the ventricles to contract which pumps blood out of the heart.
The right ventricle pumping blood to the lungs, and the left ventricle pumping blood to the body.
There are three types of circulation of the blood. These are pulmonary, systemic and portal circulation. Pulmonary circulation is where the blood is pumped to the lungs. It arrives deoxygenated from the superior and inferior vena cava into the right atrium. It then is pumped through the tricuspid valve into the right ventricle. The blood then leaves through the pulmonary valve into the pulmonary artery where it splits into the left and right pulmonary arteries and goes into the lungs and is re-oxygenated. The oxygenated blood returns from the lungs by the pulmonary veins and

Get Access