The heart has four valves that play a vital role in its function. The valves are flaps that act as one-way inlets for blood coming into a ventricle and one-way outlets for blood leaving a ventricle. Blood passes through a valve before leaving each chamber of the heart, and the valves prevent the backward flow of blood. The four heart valves are:
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Tricuspid Valve: Located between the right atrium and the right ventricle, this valve has three leaflets or cusps. It separates the top right chamber (right atrium) from the bottom right chamber (right ventricle) and opens to allow blood to flow from the right atrium to the right ventricle. It also prevents the backflow of blood from the right ventricle to the right atrium.
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Pulmonary Valve: Located between the right ventricle and the pulmonary artery, this valve has three leaflets. It opens to allow blood to be pumped from the right ventricle to the lungs (through the pulmonary artery) where it will receive oxygen. It also prevents the backflow of blood from the pulmonary artery to the right ventricle.
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Mitral Valve: Located between the left atrium and the left ventricle, this valve has two flaps. It opens to allow blood to flow from the left atrium to the left ventricle and prevents the backflow of blood from the left ventricle to the left atrium.
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Aortic Valve: Located between the left ventricle and the aorta, this valve has three leaflets. It opens to allow blood to be pumped from the left ventricle to the aorta, which then provides blood to the rest of the body. It also prevents the backflow of blood from the aorta to the left ventricle.
Heart valve disease may occur when one or more of the valves fail to open or close properly, disrupting the blood flow through the heart to the body. Valve problems may include a narrowed valve (stenosis), a leaking valve (regurgitation), or a valve with leaflets that are bulging back (prolapse) .
