Aortic Stenosis

Congenital aortic stenosis occurs in 3-6% of CHDs. It is 4 times more likely to occur in boys than in girls.

Aortic stenosis is a heart valve disorder that narrows or obstructs the aortic valve opening. Narrowing of the aortic valve prevents the valve from opening properly and obstructs the flow of blood from the left ventricle to the aorta.
Subaortic stenosis refers to a narrowing of the left ventricle just below the aortic valve, which blood passes through to go into the aorta. This stenosis limits the flow of blood out of the left ventricle. This can reduce the amount of blood that flows to the body.

Supravalvular aortic stenosis (SVAS) is a congenital narrowing of the ascending aorta which can occur as a congenital defect itself or as one component of Williams syndrome.

All increase the work the heart has to do to pump blood forward, causing pressure inside the left ventricle to increase which results in the walls of the ventricle to thicken. Unlike other muscles, thick heart muscles are not desirable. Over a long period of time, a thick ventricle can enlarge and fail. The thick muscle, increased pressure and decreased flow of oxygen rich blood to the heart muscle make the heart prone to rhythm disturbances (arrhythmia) and may cause sudden cardiac death.

Few children are symptomatic in infancy, but the incidence of problems increases dramatically in adulthood. Because the coronary arteries that feed the heart muscle with oxygen rich blood are not getting enough blood, fatigue, chest pain (angina), shortness of breath (dyspnea), decreased tolerance to exercise, and fainting(syncope) can occur. Symptoms become noticeable generally only after the stenosis has significantly progressed in severity, and the heart can no longer adapt to the abnormal pressure caused by the obstruction. Once damage becomes severe, it is irreversible. It is therefore very important to have this problem identified early and have regular follow-up and evaluation,even if symptoms are not present. A family history of a congenital heart defect and or an unidentified heart murmur are indications for evaluation by a cardiologist at which time he may perform one or more of the following tests: catherization, echocardiogram, doppler ultrasonography, chest x-ray, chest MRI, aortic angiography.

Once diagnosed, if there are no symptoms or symptoms are mild, a child may only need to be monitored by a health care provider. If symptoms become moderate to severe, a child may need to stay in the hospital and should have a physical exam every 6-12 months and an echo every 1-3 years. Medications can include diurectics, digoxin, and others medications to control heart failure. Often, these children are advised to avoid strenuous physical activities.

There are a variety of surgical procedures that can help a person with congenital aortic stenosis:

Valvuloplasty – For those high-risk patients who are poor candidates for open heart surgery, this is a less invasive procedure where a balloon is placed into an artery in the groin, advanced to the heart, placed across the valve, and inflated in hope it will relieve the obstrucation caused by the narrowed valve.

Valvotomy – This is surgery, usually done in childhood, to “free up” the native valve cusps without replacing the valve. The fused valve cusps are surgically separated and are thus able to open more easily. Valvotomy is done only when the aortic valve is still thin and pliable and has not yet become stiff and calcified. It is very effective initially, but usually reparative surgery will be required later.

Aortic Valve Replacement – There are two types of artificial valve: mechanical and tissue. While the mechanical valve is very durable, it requires lifelong anticogulation. If a blood clot would from and break off, it could result in a stroke. Often, coumadin is prescribed for those who have a mechanical valve and requires regular monitoring. A tissue valve, made of biological tissue (often pig valve), does not require longterm anticoagulation. However, it may wear out over time and will likely need replaced.

Resection of subaortic and suprs-aortic obstruction – This is the surgical removel of the obstruction. In some cases, the obstruction may grow back over time and require further surgery.

*The materials used to make valves, patches, and grafts does not grow and therefore when repairs are made during childhood, often reoperation is required in adulthood. Recent research has led scientists to grow human heart tissue. This is a very promising medical advancement for growing human valves. To read complete article, please see related links below.

Disclaimer: The facts and opinions shown in this article are as accurate and up to date as possible, but are provided as general “information resources”, which may not be relevant to individual persons. This article is not a substitute for individual assessment and always take advice from a doctor who is familiar with the particular person.
Consult you or your child’s physician regard the specific outlook for you or your child.

Related Links

Heart valve grown from stem cells
For full article, please click on following link:
http://news.bbc.co.uk/go/em/fr/-/1/hi/health/6517645.stm

Also thanks to http://www.myspace.com/chdheartfoundation for most of the Information.

The British Heart Foundation are doing booklets for Parents of children to help understand their childs heart and the booklets are also for health professionals.  

Here is the link for Aortic Stenosis
http://www.bhf.org.uk/publications/view_publication.aspx?ps=1000797