Transoesophageal Echo

A TOE is an ultrasound scan of the heart performed by passing a probe on the end of a flexible scope into your oesophagus (the ‘food pipe’). The scope is similar to the ‘camera’ used to look for a stomach ulcer. The oesophagus lies directly behind the heart, with no intervening structures, so the images are much clearer than those from the front of the chest (transthoracic echocardiography), where the chest wall, ribs and lungs get in the way. TOE is particularly useful to look at the mitral valve and to find holes in the heart, blood clots or evidence of infection (endocarditis).

What to do Before The Test?

1. Do not eat for 6 hours or take fluids for up to 4 hours before your test. This includes water except for taking tablets.

2. Unless instructed otherwise by your doctor, you should continue to take normal medications (including warfarin). Have them with just a sip of water.

3. Many patients prefer to have a sedative for the test, and so you should arrange for a responsible adult to accompany you to your appointment and escort you home as you may feel sleepy following your sedation.

4. If you have difficulty in swallowing or have ever had surgery on your throat or gullet, you should inform the department as soon as you receive your appointment. It may be necessary to have further investigations prior to this test.

What Does The Test Involve?

The test is performed on a couch or bed. A small cannula will be inserted into an arm vein (like a blood test) to administer sedation, or to perform a contrast study. An ECG and a blood oxygen monitor will be attached and you will be given oxygen through your nose. You will be asked to remove any dentures and your throat will be sprayed with local anaesthetic to make it numb. A bite guard will be placed between your front teeth. The tube is lubricated then placed at the back of the mouth. You will be asked to swallow a small number of times to help it pass into the ‘food pipe’. This may be uncomfortable, but will not be painful. Once the probe is in place, it is only mildly uncomfortable. You can breathe through your nose.

If a contrast study is required, a small injection will be made during the test, which enhances the quality of the pictures. The actual injection is painless. The liquid used is usually just salt water mixed with a little blood, but if you have any special allergies, particularly to eggs, you should tell the doctor beforehand.

What Happens After The Procedure?

Because you have had sedation, you will be asked to sit or lie in a recovery area until you feel awake enough to travel home. Information about eating and drinking will be given to you by the doctor who performs the test and the nurse. Check that the local anaesthetic has worn off by drinking cold water before taking anything hot.

The sedative can have a ‘hangover’ effect. Although you may feel fine, your reasoning, reflexes, judgement, co-ordination and skill can all be affected by having sedation