An echocardiogram is a test that builds up a moving picture of your heart using sound waves. An ultrasound is similar test that is used during pregnancies, and both are very safe. You may also have heard this test be called an echo or a transthoracic echocardiogram.

In an echo, ultrasound waves reflect against structures in your heart, which measure its size and function. It can also show which way your blood is flowing through the heart and how quickly.

Why we use echocardiograms

We use echocardiograms to help diagnose and assess a range of conditions, including:

We also use this test for regular checks on these conditions.

The test

When you have your echo, your doctor or cardiac physiologist will do the test. We will ask you to take off any clothing from your waist up and lie down on an echo bed on your back. We may also get you to roll onto your left side during the side, but we will let you know.

We will attach three sticky patches (electrodes) onto your chest, connected to the echo machine. We then place a small hand-held transducer (echo recorder) onto your chest. This will have a small amount of lubricating jelly on it to help it move. This may feel a little cold at first, but will disappear once it warms to your body temperature.

Your doctor will then take images at different positions of your heart using the echo recorder. This sends high-frequency sound waves to the heart, recording the echoes that come back. The machine receives these echoes as electrical impulses and converts them into moving images for your doctor to look at.

To find out what happens after the test and how to contact the team, click on the 'Information' tab. 

Aortic stenosis is the narrowing of the aortic valve, which controls the flow of blood in and out of the heart. 

Endocarditis is a potentially serious condition in which the lining of the heart (endocardium) becomes infected. 

Aortopathy simply means any disease of the aorta, which is the main artery of the body.

Structural heart disease is an umbrella term for a number of defects which affect the valves and chambers of the heart and the aorta. 

A VSD is a hole in the septum between the two lower chambers of the heart (the ventricles) that allows oxygenated blood and deoxygenated blood to flow through, causing the lungs and heart to work h

Scleroderma (or systemic sclerosis) is a chronic disease associated with skin thickening and changes to blood vessels, particularly those supplying the fingers and toes.

Pulmonary hypertension (PH) refers to a group of conditions where the blood pressure in the lungs is raised due to narrowing of blood vessels in the lungs. 

Ion channelopathies are a group of rare genetic conditions, caused by a gene

Cardiomyopathy is a disease that affects the heart muscle. Cardiomyopathy can often be caused by a genetic mutation, and can therefore run in families affecting one or many members, at any age.

The Trust has an inherited cardiovascular condition service, which looks after conditions such as cardiomyopathy, channelopathy and pulmonary hypertension. 

Our congenital heart disease (CHD) centre is one of the largest in the country. Clinical teams treat more than 10,000 patients with these diseases each year.


Echocardiograms are non-invasive, and are very safe for patients. There is no radiation in this type of testing, and there are no known risks or side-effects from using ultrasound.

During the echo, we may inject some dye into you, also known as contrast. This helps to improve the images we get back of your heart, and can provide extra information about your heart’s structure and blood flow. We may also get you to do certain breathing exercises, but if these are needed we will let you know.

Your echo should take between 15 to 20 minutes, unless you need to have a Doppler scan. This is a special part of the ultrasound examination that looks at how your blood is flowing in your heart. If you have this it will add another 10 to 20 minutes to your test time.

If we use any contrast during your echo, the test will then take between 30 minutes to an hour.

After the test and getting your results

Once the test is complete, your doctor or cardiac physiologist will create a report on your results. They will then let you go home and continue with your normal activities and routine. Your results are then sent to your cardiologist or doctor, ready for your next appointment.

How to find us

Royal Brompton Hospital

Level 3, Chelsea wing, Royal Brompton Hospital, SW3 6NP

Contact details

Monday to Friday 9am to 5pm
Telephone: +44 (0)20 7351 8209
Fax: +44 (0)20 7351 8604

Harefield Hospital

Echocardiography clinic room, Outpatients department, Harefield Hospital, UB9 6JH

Contact details

Monday to Friday 9am to 5pm 
Telephone: +44 (0)1895 823737 ext: 5586