Aortic stenosis

About aortic stenosis

The aortic valve sits between the left lower chamber of the heart (left ventricle) and the aorta (the body’s main artery). When the aortic valve is working normally, it opens when the heart contracts to allow oxygen-rich blood to be pumped around the body.

Aortic stenosis is the abnormal narrowing of the aortic valve, which restricts the flow of blood from the left ventricle into the aorta and around the rest of the body. This means that the heart can no longer pump blood efficiently – it needs to work harder to pump blood around your body. It also creates high blood pressure inside the left ventricle.

In response to the extra workload, the muscle of the left ventricle can thicken and enlarge.

Complications from aortic stenosis can include high blood pressure and heart failure.

The good news is there are many treatments available, including procedures or surgery to repair or replace the faulty valve.

Causes of aortic stenosis

The main causes of aortic stenosis include:

• ageing – as people get older, their heart valves can become scarred and stiffer due to a build-up of calcium. This is the most common cause of aortic stenosis in older people.
• congenital valve abnormalities – some people are born with abnormalities of the aortic valve. Over time, these abnormalities may cause the valve to narrow and thicken.
• rheumatic heart disease – a condition caused by acute rheumatic fever that can scar the aortic valve and narrow its opening.

Risk factors for aortic stenosis include:

• risk factors for heart disease, like smoking, diabetes, high blood pressure, and high cholesterol
• kidney disease
• radiation therapy to the chest.

Symptoms of aortic stenosis

People with aortic stenosis might not have any symptoms for many years. In people born with a valve abnormality, aortic stenosis can sometimes develop and can be diagnosed in teenage years.

Symptoms may appear later in life after decades of gradual narrowing of the aortic valve. The onset of symptoms may be gradual or abrupt. Symptoms often occur with physical activity and can include:

• feeling short of breath or trouble breathing
• coughing at night when lying down in bed
• feeling faint or dizzy
• palpitations (feeling of a fluttering, racing, thumping or pounding in your chest)
• chest pain or tightness
• fatigue
• loss of appetite
• loss of weight
• visual problems.

Diagnosis of aortic stenosis

There are a variety of tests and examinations to help diagnose aortic stenosis. These include:

• physical examination including listening to the heart with a stethoscope (people with aortic stenosis may have a heart murmur)
• chest X-ray, to help see if the heart is enlarged and to see if there is a build-up of calcium in the aortic valve
• electrocardiogram (ECG), to monitor the heart rate and pick up any abnormal heart rhythms. An ECG can also help assess if the left ventricle is enlarged
• echocardiogram (ultrasound scan) of the heart, to assess how well the aortic valve and the left ventricle are working
• exercise tests or ‘stress tests’, to monitor how your heart works when you’re physically active. These tests usually involve either walking on a treadmill or riding a stationary bike while connected to a heart monitor
• CT or MRI scan of the heart, to look at the size of the aorta and how severe the narrowing of the valve is.
• coronary angiogram. This is where a long, thin tube (catheter) is inserted into an artery in your wrist or groin. The catheter is threaded through the artery until it reaches your heart. A special dye is then injected into the catheter and an X-ray is taken. The X-ray shows how well your heart is pumping and if your coronary arteries are narrowed from a build-up of plaque.

Complications of aortic stenosis

Aortic stenosis can be a serious and potentially life-threatening condition. Some of the possible complications include:

• a build-up of fluid in the lungs (pulmonary oedema) – aortic stenosis causes increased pressure in the left ventricle. This can increase pressure in the blood vessels of the lungs. As a result, fluid can build up in the lungs and cause breathing difficulties
• an enlarged heart (cardiomegaly) – without treatment, aortic stenosis can cause the left ventricle to thicken and enlarge. This reduces the ventricle’s ability to pump blood around the body. The heart enlarges to try to adapt to the increased pressure
• heart failure – without treatment, aortic stenosis can cause heart failure, where the heart is not able to pump blood and oxygen around the body as well as it should
• abnormal heart rhythm– an irregular heartbeat. Changes in the shape and size of the heart due to aortic stenosis can cause the heart to beat in an irregular way. Some abnormal heart rhythms can be life-threatening and need urgent treatment.

Treatment for aortic stenosis

The type of treatment for aortic stenosis depends on how severe a person’s symptoms are. Types of treatment can include:

• lifestyle changes such as being physically active (while avoiding those activities that make symptoms worse), achieving and maintaining a healthy weight and stopping smoking
• monitoring or ‘watchful waiting’ for people without symptoms or mild cases
• procedures or surgery to replace or repair the valve.

Surgical procedures for aortic stenosis

There are three main surgical procedures for treating 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 may be surgically replaced with an artificial or tissue valve. This is a type of open-heart surgery known as aortic valve replacement. Sometimes, the person’s own pulmonary valve may be used. This is known as a pulmonary autograft or a Ross procedure.

Transcatheter aortic valve implantation (TAVI)

TAVI or transcatheter aortic valve replacement (TAVR) as it is also known, is a procedure that involves a new valve being inserted inside the damaged valve. TAVI is less invasive than open heart surgery.

Before your TAVI procedure, you'll be given a general or local anaesthetic and it usually takes 1-2 hours. A catheter (hollow tube) with a balloon at its tip is inserted into an artery either in your groin or under your collarbone. The catheter is passed into your heart and the new valve is then placed inside your aortic valve.

Balloon valvuloplasty

Balloon valvuloplasty is a procedure to stretch and widen the valve to improve blood flow into the aorta.
A catheter is inserted into a blood vessel in the groin and threaded up to the heart. The tip of the catheter is placed inside the aortic valve and then a balloon is inflated to stretch the valve. The balloon is then deflated and removed, along with the catheter.

Balloon valvuloplasty is usually used a temporary measure or to relieve symptoms when other options are not available. Further surgery or procedures may be needed later in life.

Where to get help

• Your GP (doctor)
• Cardiologist
• Heart Foundation