The Heart and Its Valves

Our hearts are key to our survival. The American Heart Association (AHA) says each day your heart beats about 100,000 times and moves 2,000 gallons of blood. (Read about "Vascular System: Arteries & Veins")

The heart is divided into four parts or chambers. The top ones are called the left atrium and right atrium and the bottom two are the left ventricle and right ventricle. The chambers each have a purpose. The atria act as reservoirs for the blood before it moves on to the larger ventricles. The ventricles are the strong pumps of the heart with the left one, the one that pushes blood out to most of the body, being the strongest.

Blood first enters the heart at the right atrium, passes through the tricuspid valve into the right ventricle. The blood is then sent out through the pulmonary valve to the lungs. It picks up oxygen and comes back to the heart at the left atrium. From there it passes through the mitral valve into the left ventricle where it is pushed through the aortic valve and out to the body. The mitral valve differs from the rest of the valves because it is made up of just two flaps; the others have three flaps. Those flaps can also be called leaflets or cusps.

The job of the valves is to keep the blood moving all in one direction, but problems can occur. Valve problems can be congenital (Read about "Congenital Heart Defects"), or they can result from aging, infection, or diseases such as Marfan syndrome (Read about "Marfan Syndrome"). Valve disorders can also lead to other heart problems such as congestive heart failure. (Read about "Congestive Heart Failure")

Below you can find information on some common valve problems.

Heart murmurs

Heart murmurs are sounds made as the blood moves through the heart. Murmurs can be caused by a number of things. Defective valves (see below) or holes in the heart walls can result in murmurs. AHA says murmurs can be caused by:

• pregnancy (Read about "Healthy Pregnancy")
• rheumatic heart disease (Read about "Rheumatic Fever")
• fever
• valve infection
• thyroid problems (Read about "Thyroid")
• anemia (Read about "Anemia")
• heart valve abnormalities
• congenital heart defects (Read about "Congenital Heart Defects")
• genetic conditions such as fragile X syndrome (Read about "Genetics" "Fragile X Syndrome")

Not all murmurs are signs of heart disease. In fact, AHA calls many of the murmurs children have, "innocent murmurs." AHA says they are very common in children. When a doctor discovers a murmur though, he or she will want to follow up with other tests to rule out any problems. Murmurs in adults almost always call for more tests to discover the reason.

See diagnosis and treatment options below.

Regurgitation

Regurgitation happens whenever a valve does not close correctly and the blood flows backward. It creates problems because the heart is now forced to work harder to move blood. Damage to either the mitral or the aortic valve, that results in regurgitation, can quickly be life threatening, according to the National Heart, Lung and Blood Institute (NHLBI). In chronic cases, enlargement of both the left atrium and ventricle can result, which can lead to other problems. Regurgitation can also happen to the valves on the right side of the heart, where the tricuspid and the pulmonary are located, but NHLBI says it's not as common.

Some signs of regurgitation problems according to AHA are:

• fatigue
• shortness of breath
• fluid retention and swelling of the extremities, especially the ankles
• arrhythmia (Read about "Arrhythmia")
• chest pain

Any of these symptoms should send you to the doctor right away for an examination.

See diagnosis and treatment options below.

Stenosis

Stenosis happens when the valve is stiff and can't open all the way. The result is, once again, that the heart must work harder to move blood.

When it happens to the aortic valve, it can be very serious. Aortic valve stenosis can develop with age, from rheumatic fever, or it can be congenital. (Read about "Rheumatic Fever" "Congenital Heart Defects") AHA says aortic stenosis can exist without any symptoms. When symptoms are present, they include chest pain and shortness of breath, according to NHLBI, which adds that the situation very often requires that the valve be replaced.

In pulmonary valve stenosis, the flow of blood from the heart to the lungs is restricted or obstructed. The disorder can be present at birth. It can also develop as a complication of another illness.

Stenosis can also occur in other valves. When it occurs in the mitral valve, blood can back up into the lungs resulting in fatigue and shortness of breath. This condition can also develop with age, or it can be congenital. The condition of stenosis on the two right side valves of the heart isn't as common as aortic or mitral valve stenosis, but does occur, often at the same time the left side is affected.

See diagnosis and treatment options below.

Mitral Valve Prolapse

Another condition can occur called mitral valve prolapse (MVP). The mitral valve is the only valve with just two flaps. It separates the left atrium and the left ventricle. Prolapse occurs when one or both of the flaps get enlarged. The valve then doesn't close correctly and some blood leaks backwards. It is not considered a serious condition according to AHA and many people don't even know they have it. It does result in heart murmurs. (See heart murmur above) NHLBI calls it common, affecting up to 10 percent of the population. Women tend to be affected more often than men. Other terms used for MVP are:

• click-murmur syndrome
• Barlow's syndrome
• balloon mitral valve
• floppy valve syndrome

AHA says a small number of MVP patients may develop angina or arrhythmia. (Read about "Angina" "Arrhythmia") In such cases, these conditions may require medical treatment.

See diagnosis and treatment options below.

Endocarditis

One serious issue for anyone with heart valve problems is bacterial endocarditis. It occurs when bacteria (Read about "Microorganisms") in the blood stream lands on abnormal heart valves or other damaged heart tissue. NHLBI says that even a mild condition such as prolapse places a person at risk for endocarditis. According to NHLBI, people with skin or lung infections are also at risk. Intravenous drug abuse is also a risk factor. Endocarditis can be fatal if not treated with antibiotics.

AHA says people are most at risk when they have dental work or surgery. People who are at risk and are planning dental work or surgery should consult their doctor about their specific needs. (Read about "Oral Health") Symptoms of bacterial endocarditis according to NHLBI are:

• heart murmur (See heart murmur above)
• chills
• night sweats (Read about "Sweating")
• loss of appetite
• joint pain

Even a minor heart condition that causes no symptoms places a person at risk for endocarditis.

See diagnosis and treatment options below.

Diagnosis and treatment options

There are a number of tests that are used to diagnose heart valve problems. They include:

• chest x-ray (Read about "X-rays")
• CT scan (Read about "CT Scan - Computerized Tomography")
• MRI (Read about "MRI - Magnetic Resonance Imaging")
• PET (Read about "PET - Positron Emission Tomography")
• cardiovascular tests such as electrocardiogram, Holter monitor, echocardiogram, cardiac catheterization and exercise or stress tests (Read about "Cardiovascular Tests")

X-rays let the doctor check for physical abnormalities. An echocardiogram, which uses sound waves, can provide information on how the valves move and direct the flow of blood. Cardiac catheterization can also provide information on how the valves are working. An EKG, in which electrodes are attached to your skin to measure the heart's electrical impulses, can provide information on the heart's rhythm. A Holter monitor, which is worn for a period of time, can also provide information on the heart's rhythm. These tests can be used alone or in combination to determine the extent of the valve problem and whether or not it needs treatment.

Some valve problems do not require treatment. This would be the case if, for example, a mitral valve prolapse is not causing any symptoms. Mitral valve prolapse that is causing symptoms can be treated with medications, for example beta blockers if there is rapid heartbeat, or anti-coagulants if the person with MVP also has a history of stroke.

Serious valve problems may require surgery. The repair or replacement of defective valves can be a lifesaving procedure. It is also one that must be carefully discussed with your doctor, based on the risk of surgery and the benefits available from surgery. (Read about "Learn About Your Procedure") In some cases, medications alone may provide enough relief of symptoms and can be the preferred option. In cases of mitral valve disorders, repair can be an option. The Society of Thoracic Surgeons (STS) says defects of the aortic valve are more likely to need valve replacement. For some patients, minimally-invasive robotic-assisted valve repair or replacement is an option. (Read about "Robotic Surgery")

NHLBI says there are two general types of valves used in valve replacement: mechanical and bioprosthetic (made from animal or human tissue). STS says mechanical valves tend to be more durable. Among the questions to ask your doctor when considering valve replacement:

• Will I need long-term anticoagulants?
• How long will the replacement last?
• What are the benefits of the type of valve you recommend?
• What are the risks?

According to NHLBI, the major risk of prosthetic heart valves is stroke, due to the formation of clots that enter the brain. (Read about "Stroke") NHLBI says, in general, the risk of stroke is higher for mitral valve replacement than for aortic valve replacement. ATA also says patients who have valve replacement may need to take antibiotics whenever having dental work, and should always tell a doctor about their valve surgery before any anesthesia or surgical procedure. (Read about "Anesthesia")

Related Information:

    Cardiovascular Tests

    Heart Attack

    Heart Risks

    Glossary of Stroke Terms

    Glossary of Heart Terms