Heart Valve FAQs

The heart is a pump for the body. Over a lifetime the heart will beat more than two billion times, pumping about 180 million liters of blood. Two fists together will be the approximate size of a human heart. The heart is divided into four chambers; two atria and two ventricles. There is one atrium and one ventricle on each side of the heart.

When blood flows through the heart, it flows first through an atrium and then into a ventricle. Within each of the four chambers there is a valve which allows blood to pass into the next chamber.

The left side of the heart must produce enough pressure, that is approximately ten times higher than than the pressure created on the right side of the heart, because it is the area of the heart that returns oxygenated blood to the entire body. Oxygenated blood is sent to the left atrium of the heart by the pulmonary veins. Blood then flows from the left atrium, through the mitral valve, into the left ventricle. Blood is then transported to the body through the aorta, the largest artery in the body. Because of the pressure it must maintain to perform its function, the heart valves on the left side of the heart are most often affected by heart valve disease.

After flowing through the body, the blood has very little oxygen left. To obtain a new supply of oxygen, the deoxygenated blood needs to flow to the lungs. To get to the lungs, the blood needs to return to the heart, entering through the right atrium. The blood is pumped from the right atrium through the tricuspid valve, pushing the tricuspid valve's leaflets aside. As the ventricle starts to contract, drawing in the blood, the tricuspid valve's leaflets snap shut and the cusps of the pulmonary valve open, allowing blood to flow out of the ventricle through the pulmonary artery and on to the lungs. As the ventricle relaxes, the pulmonary valve then closes. After leaving the right ventricle, the blood heads towards the lungs to give up carbon dioxide and water vapor in exchange for the oxygen the body needs. The blood then returns to the heart via the pulmonary veins and enters the left atrium. Once the blood moves to the left ventricle, it is ready to start its circuit, all over again, to the body.

What is mitral valve prolapse?

If a mitral valve is not as tight as it should be, it may allow one of the portions of the valve to bend backwards towards the upper chamber (left atrium) during the heart's contraction. This is called prolapse. This movement can create a clicking sound that can be heard with a stethoscope.

Mitral valve prolapse is not uncommon and affects between five to twenty percent of the general population, most of them women. The symptoms of mitral valve prolapse usually begin after the early teenage years, approximately age 14 in girls and in 15 in boys, yet people of any age may be affected.

What is mitral valve regurgitation?

Mitral valve regurgitation occurs when there is a small leakage of blood backwards into the upper chamber of the heart (left atrium) from the lower chamber of the heart (left ventricle). While this can be heard as a symptom of a heart murmur, the heart is still able to function normally. The heart still pumps and receives an adequate blood supply. Most cases of mitral valve prolapse do not tend to worsen over time yet it can cause a shortness of breath, irregular heartbeats or chest pain.

What causes mitral valve stenosis?

Mitral valve stenosis appears over the course of time and symptoms may not appear for 10 to 20 years. Most cases of mitral valve stenosis appear in people who have had rheumatic fever, which can cause damage to heart valves. Symptoms can be triggered by an episode of atrial fibrillation (rapid, incomplete contractions of the atria), pregnancy, respiratory infection, endocarditis, or other cardiac disorders.

What is aortic valve stenosis?

Aortic valve stenosis is a narrowing of the aortic valve, the opening that allows blood to flow into the aorta. The valve is made up of three parts, called leaflets, which open and close allowing blood to flow in and out. If the passageway narrows and the valve cannot open properly, blood flow is disrupted, which can lead to shortness of breath, chest pain and heart failure.

What is aortic regurgitation?

Aortic regurgitation, also known as aortic insufficiency, occurs when the aortic valve does not close tightly, causing blood to leak back into the heart. The aortic valve connects the heart to the aorta and helps blood flow through the body. The abnormal functioning of the valve can occur suddenly or gradually, leading to heart palpitations, endocarditis or heart failure.

Additional Resources