Basic Principles of Adult Cardiac Surgery
The heart is a mechanical device designed to pump blood around the body. Like any pump that pumps liquid it requires two particular sets of components. Firstly, a series of one-way valves to ensure the blood goes in one direction, and secondly, a fuel supply to provide the energy for pumping. The heart has its own fuel lines, the coronary arteries, which provide oxygen and nutrients for the heart muscle. The heart is, in fact, two pumps. The right side receives blood from the body which it pumps through the lungs, where the blood picks up oxygen, and back to the left side of the heart where the blood now containing new oxygen is then pumped around the whole body. The left side of the heart is stronger because it has to pump blood further.
The heart is a muscle pump, which contains four one-way valves to ensure blood flows in one direction. These valves may become narrowed (stenotic) or leaky (regurgitant) and one or more may need to be repaired or replaced.
The right side of the heart contains two valves: the tricuspid valve where blood enters the main pumping chamber, the right ventricle, and the pulmonary valve where the blood leaves the right ventricle to go to the lungs. Similarly when blood returns from the lungs it enters the main pumping chamber, the left ventricle, through the mitral valve and is then pumped out of the heart through the aortic valve. All this requires energy, which is delivered to the heart muscle in the form of nutrients and oxygen by the coronary arteries.
Further useful information can be found at the following NHS Choices website
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