Heart valve disease occurs when your heart’s valves do not work the way they should. Your heart valves lie at the exit of each of your four heart chambers and maintain one-way blood flow through your heart. The four heart valves make sure that blood always flows freely in a forward direction and that there is no backward leakage.
Blood flows from your right and left atria into your ventricles through the open mitral and tricuspid valves. When the ventricles are full, the mitral and tricuspid valves shut. This prevents blood from flowing backward into the atria while the ventricles contract (squeeze). As the ventricles begin to contract, the pulmonic and aortic valves are forced open and blood is pumped out of the ventricles through the open valves into the pulmonary artery toward the lungs, the aorta, and the body. When the ventricles finish contracting and begin to relax, the aortic and pulmonic valves snap shut. These valves prevent blood from flowing back into the ventricles. This pattern is repeated over and over, causing blood to flow continuously to the heart, lungs and body.
Types
There are several types of valve disease:
• Valvular stenosis. This occurs when a valve opening is smaller than normal due to stiff or fused
leaflets. The narrowed opening may make the heart work very hard to pump blood through it. This can lead to heart failure and other symptoms (see below). All four valves can be stenotic (hardened, restricting blood flow); the conditions are called tricuspid stenosis, pulmonic stenosis, mitral stenosis or aortic stenosis.
• Valvular insufficiency. Also called regurgitation, incompetence or “leaky valve”, this occurs when a valve does not close tightly. If the valves do not seal, some blood will leak backwards across the valve. As the leak worsens, the heart has to work harder to make up for the leaky valve, and less blood may flow to the rest of the body. Depending on which valve is affected, the conditioned is called tricuspid regurgitation, pulmonary regurgitation, mitral regurgitation or aortic regurgitation.
What Causes Valvular Heart Disease?
Valve disease can develop before birth (congenital) or can be acquired sometime during one’s lifetime. Sometimes the cause of valve disease is unknown.
Congenital valve disease. Most often affects the aortic or pulmonic valve. Valves may be the wrong size, have malformed leaflets, or have leaflets that are not attached to the annulus correctly.
Bicuspid aortic valve disease is a congenital valve disease that affects the aortic valve. Instead of the normal three leaflets or cusps, the bicuspid aortic valve has only two. Without the third leaflet, the valve may be stiff (unable to open or close properly) or leaky (not able close tightly).
Acquired valve disease. This includes problems that develop with valves that were once normal. These may involve changes in the structure or your valve due to a variety of diseases or infections, including rheumatic fever or endocarditis.
Rheumatic fever is caused by an untreated bacterial infection (usually strep. throat). Luckily, the introduction of antibiotics to treat this infection has dramatically reduced the numbers of this infection. The initial infection usually occurs in children, but the heart problems associated with the infection may not be seen until 20-40 years later. At that time, the heart valves become inflamed, the leaflets stick together and become scarred, rigid, thickened and shortened. This leads to mitral regurgitation.
Endocarditis occurs when germs, especially bacteria, enter the bloodstream and attack the heart valves, causing growths and holes in the valves and scarring. This can lead to leaky valves. The germs that cause endocarditis enter the blood during dental procedures, surgery, IV drug use, or with severe infections. People with valve disease (except mitral valve prolapse without thickening or regurgitation/leaking) are at increased risk for developing this life-threatening infection.
There are many changes that can occur to the valves of the heart. The chordae tendinea or papillary muscles can stretch or tear; the annulus of the valve can dilate (become wide); or the valve leaflets can become fibrotic (stiff) and calcified.
Mitral valve prolapse (MVP) is a very common condition, affecting 1 to 2 percent of the population. MVP causes the leaflets of the mitral valve to flop back into the left atrium during the heart’s contraction. MVP also causes the tissues of the valve to become abnormal and stretchy, causing the valve to leak. The condition rarely causes symptoms and usually doesn’t require treatment.
Other causes of valve disease include: coronary artery disease, heart attack, cardiomyopathy (heart muscle disease), syphilis (a sexually transmitted disease), hypertension, aortic aneurysms, and connective tissue diseases. Less common causes of valve disease include tumors, some types of drugs and radiation.
What Are the Symptoms of Valve Disease?
Shortness of breath and/or difficulty catching your breath. You may notice this most when you are active (doing your normal daily activities) or when you lie down flat in bed. You may need to sleep propped up on a few pillows to breathe easier.
Weakness or dizziness. You may feel too weak to carry out your normal daily activities. Dizziness can also occur, and in some cases, passing out may be a symptom.
Discomfort in your chest. You may feel a pressure or weight in your chest with activity or when going out in cold air.
Palpitations. This may feel like a rapid heart rhythm, irregular heartbeat, skipped beats or a flip-flop feeling in your chest.
Swelling of your ankles, feet or abdomen. This is called edema. Swelling may occur in your belly, which may cause you to feel bloated.
Rapid weight gain. A weight gain of two or three pounds in one day is possible. Symptoms do not always relate to the seriousness of your valve disease. You may have no symptoms at all and have severe valve disease, requiring prompt treatment. Or, as with mitral valve prolapse, you may have severe symptoms, yet tests may show your valve leak is not significant.
How Are Valve Diseases Diagnosed?
Your heart doctor can tell if you have valve disease by talking to you about your symptoms, performing a physical exam, and giving you other tests.
During a physical exam, your doctor will listen to your heart to hear the sounds the heart makes as the valves open and close. A murmur is a swishing sound made by blood flowing through a stenotic or leaky valve. Your doctor can also tell if your heart is enlarged or if your heart rhythm is irregular.
The doctor will listen to your lungs to hear if you are retaining fluid in your lungs, which shows your heart is not able to pump as well as it should.
By examining your body, the doctor can find clues about your circulation and the functioning of your other organs.
After the physical exam, the doctor may order diagnostic tests. These may include:
• Echocardiography
• Transesophageal echocardiography
• Cardiac catheterization (also called an angiogram)
• Radionuclide scans
• Magnetic resonance imaging (MRI)
By looking at the results, repeated over time, your doctor can also see the progress of your valve disease. This will help him or her make decisions about your treatment.
How Is Heart Valve Disease Treated?
Treatment for heart valve disease depends on the type and severity of valve disease. There are three goals of treatment for heart valve disease: protecting your valve from further damage; lessening symptoms; and repairing or replacing valves.
Protecting your valve from further damage.
If you have valve disease, you are at risk for developing endocarditis, a serious condition. People who have mitral valve prolapse without thickening or regurgitation/leaking are not at risk of developing endocarditis.
You are still at risk for endocarditis, even if your valve is repaired or replaced through surgery. To protect yourself:
• Tell your doctors and dentist you have valve disease. You may want to carry an identification card with this information. The American Heart Association website (www.americanheart.org) has a bacterial endocarditis wallet card that you may download; or call your local American Heart Association office or the national office at 1-800-AHA-USA1.
• Call your doctor if you have symptoms of an infection (sore throat, general body aches, fever).
• Take good care of your teeth and gums to prevent infections. See your dentist for regular visits.
• Take antibiotics before you undergo any procedure that may cause bleeding, such as any dental work (even a basic teeth cleaning), invasive tests (any test that may involve blood or bleeding), and most major or minor surgery. Your doctor can provide you with a card that provides specific antibiotic guidelines.
Medications. You may be prescribed medications to treat your symptoms and to lessen the chance of further valve damage. Some medications may be stopped after you have had valve surgery to correct your problem. Other medications may need to be taken all your life. Medications may include:
Common Types of Medications What They Do
Diuretics (“water pills”) Remove extra fluid from the tissues and bloodstream; lessen the symptoms of heart failure
Antiarrhythmic medications Control the heart’s rhythm
Vasodilators Lessen the heart’s work. Also encourages blood to flow in a forward direction, rather than backwards through a leaky valve.
ACE inhibitors A type of vasodilator used to treat high blood pressureand heart failure
Beta blockers Treat high blood pressure and lessen the heart’s work by helping the heart beat slower and less forcefully. Used to decrease palpitations in some patients.
Anticoagulants (“blood thinners”) Prolong the clotting time of your blood, if you are at risk for developing blood clots on your heart valve.
Follow your doctor’s orders when taking medications. Know the names of your medications, what they are for, and how often to take them.
Surgery and Other Procedures:
The diagnostic tests your heart doctor orders help to identify the location, type, and extent of your valve disease. The results of these tests, the structure of your heart, your age, and your lifestyle will help your cardiologist (heart doctor), surgeon, and you decide what type of procedure will be best for you.
Surgical options include heart valve repair or replacement. Valves can be repaired or replaced with traditional heart valve surgery or a minimally invasive heart valve surgical procedure. Heart valves may also be repaired by other procedures such as percutaneous balloon valvotomy.
Kaynak: http://www.medicinenet.com/heart_valve_disease/article.htm
