Definition The left side of the heart pumps oxygen-rich blood into the aorta, which is the main artery in the body. Before the blood reaches the aorta, it collects in an area called the left ventricle. The left ventricle squeezes, or contracts, regularly. That sends blood through the aortic valve and into the aorta.
Aortic stenosis is a narrowing of the opening of the aortic valve. This partly blocks blood flow from the left ventricle.
What is going on in the body? The aortic valve lies between the left ventricle and the aorta. Normally the valve opens when the ventricle contracts so that oxygen-rich blood can be pumped into the aorta and out to the rest of the body.
When aortic stenosis has occurred, the opening of the valve is narrower than normal. This reduces the amount of blood flow to the body.
What are the signs and symptoms of the condition? Common symptoms include fainting and trouble breathing, especially during strenuous activity. The coronary arteries, which carry oxygen to heart muscles, may be deprived of blood. That can cause heart pains called stable angina or unstable angina. This type of pain has been described as a tightness, squeezing ,or pressing sensation in the middle of the chest. The pain commonly extends into the left shoulder and down the arm.
The severity of symptoms is not always related to the severity of the disease. In fact, people sometimes die suddenly from aortic stenosis without having had symptoms.
What are the causes and risks of the condition? The causes of aortic stenosis include:
calcium deposits that harden, or calcify, the valve
What can be done to prevent the condition? In many cases, nothing can prevent the disease. Proper treatment of rheumatic fever with antibiotics can prevent damage to the aortic valve.
How is the condition diagnosed? Murmurs and abnormal heart sounds can be heard during a physical examination. A test of heart's electrical activity called an electrocardiogram (ECG) can demonstrate changes in the left ventricle. A chest x-ray may reveal a calcified valve and changes in the size of the heart. Echocardiography uses sound waves to see and assess damage to the valve, and the size and function of the left ventricle.
Cardiac catheterisation is useful. In this procedure, a tube called a catheter is passed into the heart through a vein or artery usually in the groin. This tube can measure the pressure across the valve. A dye can be injected through the tube. A special x-ray camera allows the doctor to see the dye being pumped through the heart. This helps to check the condition of the coronary arteries.
What are the long-term effects of the condition? Progressive narrowing of the aortic valve deprives body organs of blood. The heart may thicken and hold less blood. The coronary arteries that supply the heart itself with oxygen are also deprived of blood. Other serious long-term effects are:
enlargement of the left ventricle. Known as cardiomyopathy, this condition reduces the amount of blood it can hold. That cuts down the output of the heart still more.
sudden death
What are the risks to others? There are no risks to others.
What are the treatments for the condition? A goal of treatment is to allow the heart to get more blood into general circulation. Heart medications can help improve overall blood supply to the body and the heart. They can also help reduce the symptoms of angina and pulmonary oedema.
People who have trouble breathing or angina need surgical care, with:
corrective surgery to replace the damaged valve.
balloon valvuloplasty, an invasive technique that lowers the pressure across the valve by slightly enlarging the opening. This is usually done when someone is not stable enough for corrective surgery. This is usually only a temporary measure to relieve symptoms.
What are the side effects of the treatments? The side effects of balloon valvuloplasty include:
a risk of the valve narrowing again
a high risk of death
Valve replacement surgery may cause bleeding, infection, and occasionally death. Side effects of heart medications can range from upset stomach to worsening of symptoms.
What happens after treatment for the condition? Successful replacement of the valve restores normal blood flow. The long-term outcome is usually very good. Some artificial valves require that the person take:
antibiotics before and after future surgeries and dental work to avoid serious heart infections
How is the condition monitored? After surgery, people are monitored to:
see if symptoms lessen
watch for bleeding
check the blood for damaged cells by doing frequent blood tests
Any recurrence of symptoms should be reported to the doctor right away.
Some artificial valves wear out over a period of years. Their function is monitored and the valves are replaced as necessary.
Author: Eric Berlin, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
