It is a valve in the human heart located between the left ventricle and the aorta.
It is one of the two semilunar valves of the heart, the other is the pulmonary valve. The heart has four valves and the other two are the mitral and tricuspid valves.
The aortic valve opens when the heart contracts to pump oxygenated blood from the left ventricle into the aorta, the body’s main artery.
If this valve narrows, it means that the heart can no longer pump blood efficiently; you must work harder to pump blood around your body. It also creates high blood pressure within the left ventricle.
In response to the additional workload, the left ventricular muscle thickens (concentric hypertrophy) and the chamber itself can eventually swell.
Without treatment, death from congestive heart failure is possible. About four out of every 1,000 people are believed to have aortic stenosis.
Aortic stenosis is the abnormal narrowing of the aortic valve, which restricts the flow of blood from the left ventricle of the heart to the aorta.
Symptoms of aortic stenosis
Aortic stenosis may have no symptoms (be asymptomatic) for many years. This is why the condition, which may have been present since before birth, is often diagnosed during adolescence.
Symptoms may appear later in life after decades of gradual progressive narrowing of the aortic valve.
The onset of symptoms can be gradual or abrupt and may include:
- Short of breath.
- Breathing problems made worse by physical activity.
- Cough at night when lying in bed.
- Heart palpitations
- Chest pains, from the heart (angina).
- Visual problems.
Causes of aortic stenosis
Some of the causes of aortic stenosis include:
- Congenital valve abnormalities : Some people are born with aortic valve abnormalities. Over time, these abnormalities can cause the valve to narrow.
- Rheumatic heart disease : is a condition that can heal the aortic valve and narrow its opening.
- Calcium deposits – A build-up of calcium can stiffen the aortic valve and interfere with its proper function. This is the most common cause of aortic stenosis in people age 70 and older.
Complications of aortic stenosis
Aortic stenosis can be a serious and life-threatening condition.
Some of the possible complications include:
- Pulmonary edema (fluid in the lungs) : the back pressure of the blood within the heart changes the pressure in the blood vessels of the lungs. This causes fluid build-up and breathing difficulties.
- Cardiomegaly (enlarged heart) : Without treatment, the left ventricle can thicken and enlarge. This reduces the ventricle’s ability to pump blood.
- Heart failure: Aortic stenosis compromises the functioning of the left side of the heart, but it can also affect the right side of the heart in severe cases
- Heart arrhythmia (an irregular heartbeat): Some arrhythmias in the ventricles can be associated with cardiac death, such as “ventricular fibrillation,” when the ventricles are reduced to trembling instead of beating.
Diagnosis of aortic stenosis
Aortic stenosis is diagnosed by a series of tests that include:
- Physical exam that includes listening to the heart with a stethoscope.
- Chest X-ray.
- Electrocardiogram (ECG) to monitor the heart rate, detect any unusual rhythms, and evaluate the thickening of the left ventricle.
- Echocardiogram (ultrasound) of the heart to evaluate the function of the aortic valve and the left ventricle.
- Cardiac catheterization (a thin tube is inserted into a blood vessel in the groin or wrist and wound up to the heart). This may include left ventriculography, which includes the use of a dye to make the heart show up more clearly on the x-ray.
- Coronary angiogram to assess for coronary artery disease in addition to recognized aortic valve disease.
Treatment of aortic stenosis
Treatment for aortic stenosis may include:
- Monitoring: for mild or asymptomatic cases.
- Hospitalization: for moderate to severe cases.
- Lifestyle patterns: such as staying physically active while avoiding strenuous exercise, controlling weight, and avoiding smoking.
Procedures or surgery to replace or repair the valve
Surgical procedures for aortic stenosis
There are three main surgical procedures to treat aortic stenosis:
- Aortic valve replacement.
- Transcatheter aortic valve implantation (TAVI).
- Balloon valvuloplasty.
Aortic valve replacement
If the aortic valve is too damaged to be repaired, it can be surgically replaced with an artificial or tissue valve. This is known as aortic valve replacement.
Sometimes the person’s pulmonary valve can be used. This is known as a pulmonary autograft or Ross operation.
The transcatheter aortic valve implant (TAVI)
TAVI is a relatively new procedure that involves inserting a new valve without the need for open heart surgery.
It is generally only suitable for older people who are at too high a risk for conventional surgical replacement.
When performing a balloon valvuloplasty, a catheter is inserted into a blood vessel in the groin and wound around the heart. The tip of the catheter is placed inside the aortic valve and then a balloon is inflated.
This helps stretch and widen the valve and improve blood flow to the aorta.
The balloon is then deflated and then the catheter is removed
Balloon valvuloplasty does not cure the condition, and more surgical treatment may be needed in the future.
This procedure is generally used as a temporary measure or to relieve symptoms when no other options are available.