The heart has four valves that control blood flow through your heart. They are called the aortic, mitral, pulmonary, and tricuspid valves, and each is made of flaps of tissue called leaflets. The aortic valve is like a gate between the largest chamber of the heart, the left ventricle, and the rest of the body. Sometimes, usually as people age, the aortic valve stops opening properly and no longer lets enough blood through. This condition is called aortic stenosis. Some patients are non-symptomatic. But if the condition becomes severe enough, people may complain of dizziness, fainting, trouble breathing, or chest pain. What is aortic stenosis The aortic valve consists of three leaflets that open and close to channel blood from the left ventricle, to the aorta, which feeds blood to the rest of the body. Aortic valve stenosis occurs when the leaflets, or cusps, of the aortic valve are restricted in their motion and cannot fully open.  This narrows the opening of the aortic valve to allow blood to go from the heart to the aorta. When it becomes so narrow that it prevents blood flow from the heart, it may cause cardiac problems or symptoms. Aortic stenosis could be caused by many diseases and problems. One cause is rheumatic fever, a complication of strep throat and scarlet fever. Another cause may be calcification of the aortic valve, which can occur with age and is the most common cause in the US. Congenital abnormalities or prior radiation therapy to the chest can also cause aortic valve disease.  Aortic stenosis is three times more common in men than in women and is one of the most common valve diseases associated with aging. It is estimated that up to 7% of the population over age of 65 may have aortic stenosis. In elderly patients, severe aortic stenosis is often caused by calcification (mineral deposits) on the leaflets of the aortic valve. Over time the leaflets stiffen, reducing their ability to fully open and close. When the leaflets don’t fully open, your heart has to work harder to push blood through the aortic valve to your body. Eventually, your heart can weaken; increasing the risk of heart failure. Symptoms generally do not appear until middle age or later and can indicate the need for surgical valve replacement. The most common symptoms are shortness of breath, chest pain, fatigue and fainting. There is no drug or medical therapy for aortic stenosis. Diuretics can be used if heart failure due to aortic stenosis occurs but are challenging. When aortic stenosis is severe, it can traditionally only be solved with aortic valve replacement surgery which involves open-heart surgery and stopping the heart while on cardiopulmonary bypass to replace the malfunctioning valve. Newer techniques to replace the stenotic aortic valve without surgery have been developed and techniques and technology for this are slowly improving. Symptoms The symptoms of aortic stenosis may not appear until the disease is far advanced. If you have any of these symptoms, you should seek help immediately.  The symptoms include: Fainting, a sudden and brief loss of consciousness (syncope) or dizziness after periods of inactivity. Weakness, fatigue or shortness of breath with activity. Feeling winded and tired when walking or lying down. An uncomfortable awareness or feeling that the heart is beating hard, rapidly or irregular (palpitations) Cough without illness Chest pain or discomfort (angina) which may radiate to the neck, back or arms (It often feels like a tightness, pressure, or oppression and usually increases with exercise and is relieved with rest). Decreased urine production, even with normal liquid intake Dizziness or lightheadedness Signs and examinations To confirm the diagnosis of aortic stenosis, medical tests are performed. The most common test is an echocardiogram.  An echocardiogram uses sound waves to take pictures of the heart and heart valves.  The Doppler technique is performed to determine the severity of the stenosis and can measure the amount of blood that flows through the valve. A chest x-ray could reveal an enlarged heart.  An electrocardiogram (ECG) may also suggest an enlarged heart. Less frequently performed tests include angiography or cardiac catheterization (especially prior to considering surgery to replace the aortic valve), which consists of introducing a catheter into the heart and injecting a special contrast agent through the catheter and taking moving x-rays of the heart and blood vessels. Treatment: Overview When aortic stenosis is severe and patients are symptomatic, the best treatment is to replace the old aortic valve with a new one. This is called aortic valve replacement (AVR). Options If there are no symptoms, or if symptoms are mild, patients only need to be observed. If symptoms are serious it may require hospitalization. Medications may be needed to prevent heart failure. Symptomatic people may need to avoid vigorous physical activities. People with symptoms of aortic stenosis who have difficulty breathing, chest pain and syncope should go to the doctor immediately. Patients who have only mild symptoms must undergo a physical examination every 6 to 12 months, with an electrocardiogram performed every 1 to 3 years. Generally, an echocardiogram is done each year to confirm that the aortic stenosis has not progressed. In general, the recommendation to increase or regularly participate in physical activity applies to patients with heart valve disease, especially when they also have coronary artery disease. However, they must take some precautions. For example, physical activity is usually unrestricted in patients with mild aortic stenosis; these patients can often even participate in competitive sports. It may take decades of progression to go from detection of the abnormality to a need for intervention. On the other hand, patients with moderate-to-severe aortic stenosis should avoid sports that place a high demand on large muscle groups.  Because one-size does not fit all when it comes to valve disease and physical activity, it is important to check with your cardiologist for guidelines regarding appropriate exercise.  It may be helpful for certain patients with valve disease to undergo a medically supervised exercise test before they begin exercising independently. The traditional treatment for symptomatic aortic stenosis is surgical valve replacement. Aortic stenosis can be cured with surgical treatment, with a potential ongoing risk of arrhythmias and heart failure. A person may not have symptoms until complications arise. The time to perform a surgical aortic valve replacement is when the risk of the aortic stenosis outweighs than the risk of the surgery.