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Valve Diseases

Types of Valves

Pressure changes behind and in front of the valves allow them to open their flap–like “Doors” (called cusps or leaflets) at just the right time, then close them tightly to prevent a backflow of blood.

There are 4 types of valves in the heart

Tricuspid valve.
Pulmonary valve.
Mitral valve.
Aortic valve.

Oxygen–depleted blood returning from the body flows into the heart’s right atrium (upper–right chamber). From there, it is forced through the tricuspid valve into the right ventricle (lower–right chamber). The right ventricle pumps the blood through the pulmonary valve and into the lungs, where the blood can pick up oxygen. As the right ventricle is preparing to push blood through the pulmonary valve, the tricuspid valve closes to prevent blood from flowing back into the right atrium.

Oxygen–rich blood returning from the lungs flows into the left atrium (upper–left chamber). This blood is forced through the mitral valve into the left ventricle (lower–left chamber) with the mitral valve sealing off to prevent backflow. At the same time that the right ventricle is pumping oxygen–depleted blood into the lungs, the left ventricle is pushing oxygen–rich blood through the aortic valve and on to all of the body’s organs.

Two types of problems can disrupt blood flow though the valves
Regurgitation
It is also called as insufficiency or incompetence which occurs when a valve doesn’t close properly and blood leaks backward instead of continuing in the proper one–directional flow. If too much blood flows backward, only a small amount can travel forward to the body’s organs. The heart tries to make up for this by working harder, but eventually the heart will become enlarged (dilated) and less able to pump blood through the body.

Stenosis
It occurs when the leaflets do not open wide enough, reducing the amount of blood that can flow through the valve. Stenosis results from the leaflets thickening, stiffening, or fusing together. Because of the narrowed valve, the heart must work harder to maintain circulation.

Causes of valve disease

Myxomatous degeneration, which is a weakening of the valve tissue caused by metabolic changes in the body. This occurs most often in the elderly and commonly affects the mitral valve.
Calcific degeneration, which causes a buildup of calcium on the aortic or mitral valves, causing the valves to thicken.
Congenital (inherited) defects, such as an irregularly shaped aortic valve or a narrowed mitral valve.
Infective endocarditis, which is an infection in the lining of the heart’s walls and valves (the endocardium).
Coronary artery disease.
Heart attack.

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