Transoesophageal echocardiogram

Published by Bupa's Health Information Team, May 2010.

This factsheet is for people who are having a transoesophageal echocardiogram (TOE), or who would like information about it.

An echocardiogram uses ultrasound to produce moving real-time images of the inside of your heart. In a TOE, the ultrasound probe is placed in your oesophagus (the pipe that goes from the mouth to the stomach), to take the images of your heart. It can help to diagnose heart problems.

About transoesophageal echocardiograms

An echocardiogram is used to check the structure of your heart and how well it's working. It uses an ultrasound probe to get a moving picture of your heart.

Transoesophageal means that the images are taken from inside your oesophagus, the pipe that joins your mouth to your stomach. An echocardiogram done this way gives a clearer view of your heart than a standard echocardiogram, which takes the images through your chest. The test can also give a detailed view of the heart valves. You may have a TOE to check for:

• problems with your heart valves
• infection of the lining inside your heart
• swelling of, or tears in, your aorta (the largest artery in your body)
• damage to your heart muscle
• blood clots

A transoesophageal echocardiogram can also be used to take images of your heart during heart procedures, such as surgery and cardiac catheterisation.

What are the alternatives?

There are a number of alternatives to having a transoesophageal echocardiogram. Some of these are listed below.

• Electrocardiogram (ECG). This is a test that measures the electrical activity of your heart to see how well it's working.
• A standard echocardiogram. For this type of echocardiogram, the ultrasound probe is moved over your chest.
• A stress echocardiogram. This is similar to a standard echocardiogram, but it's carried out when your heart is under stress (either after exercise or after being given a medicine)
• Radionuclide test. During this test you're injected with a harmless, radioactive substance when you're resting and when your heart is under stress. As it travels through your heart, the radioactive substance is seen with a special camera.
• Cardiac MRI (magnetic resonance imaging) test. An MRI scan uses magnets and radiowaves to produce images of the inside of the body.

Preparing for a transoesophageal echocardiogram

A TOE is usually carried out in hospital by a cardiologist (a doctor specialising in conditions of the heart and blood vessels). You will be asked to attend the hospital as an out-patient and should follow any instructions given to you in your appointment letter.

You shouldn't eat or drink anything for at least six hours before the test. If you have diabetes, you may be asked to not take your diabetes medication before the test. You should take any other medication as usual. You will also need to arrange for someone to take you home after the test.

Your doctor will discuss with you what will happen before, during and after your procedure, and any pain you might have. This is your opportunity to understand what will happen, and you can help yourself by preparing questions to ask about the risks, benefits and any alternatives to the procedure. This will help you to be informed, so you can give your consent for the procedure to go ahead, which you may be asked to do by signing a consent form.

What happens during a transoesophageal echocardiogram

You may have to stay in hospital for a few hours for a TOE. The procedure takes place in a private room, and you may be asked to change into a hospital gown. You will have a local anaesthetic sprayed on the back of your throat to numb it and to help you to swallow the ultrasound probe. You may also have a sedative injection, which will help you to relax and relieve any anxiety. You will be given a plastic mouth guard to protect your teeth.

You will be asked to lie on your side and to swallow a small probe, which is on the end of a flexible tube. You will be able to breathe normally. The probe gives out ultrasound waves, which bounce off the structures of your heart and are picked up by the echocardiogram machine. The images of your heart will be displayed on a screen. When the test is finished the doctor will gently take the tube out.

Sometimes a contrast liquid may be injected into your vein during the test. This helps to show certain parts of your heart more clearly.

The procedure itself usually takes 15 to 20 minutes. You will normally be given some time to rest after it has finished.

What to expect afterwards

If you have had a sedative, you may need to stay in hospital for a couple of hours. Sedation temporarily affects your co-ordination and reasoning skills, so you must not drive, drink alcohol, operate machinery or sign legal documents for 24 hours afterwards. If you're in any doubt about driving, contact your motor insurer so that you're aware of their recommendations, and always follow your doctor's advice.

You shouldn't eat or drink anything for the first few hours after a TOE, until your local anaesthetic has worn off.

The results of your echocardiogram are usually sent to your cardiologist or to the doctor who requested the test, for example your GP. He or she will discuss the results with you at your next appointment.

What are the risks?

Transoesophageal echocardiogram is commonly performed and generally safe. However, in order to make an informed decision and give your consent, you need to be aware of the possible side-effects and the risk of complications of this procedure.

Side-effects

Side-effects are the unwanted but mostly temporary effects you may get after having the procedure.

The back of your throat may feel sore and swallowing may be uncomfortable after a TOE. This should wear off very quickly.

Complications

This is when problems occur during or after the procedure. Most people aren't affected.

You may have small injuries to your mouth or oesophagus. These don't normally need any treatment.

There is a small risk of damage to your teeth. If you have dental crowns or bridges, there is also a small chance that these may get damaged. You should tell your doctor if you have a dental plate (false teeth) and remove it before the investigation.

If you had a contrast liquid injected during the test, there is a small risk of bruising around the place when the injection was given. There is also a very small risk of an allergic reaction to the contrast liquid.

The exact risks are specific to you and differ for every person, so we haven't included statistics here. Ask your doctor to explain how these risks apply to you.

For answers to frequently asked questions on this topic, see Common questions.

For sources and links to further information, see Resources.