Transoesophageal Echocardiogram (TEE)

Transoesophageal Echocardiogram (TEE) - What it is

Transoesophageal echocardiogram (TEE) is a diagnostic procedure similar to the echocardiogram which you might have undergone previously. An ultrasound transducer is mounted onto the tip of a long and slim special tube called the TEE probe. This probe will be introduced into your oesophagus (the passage between your mouth and stomach) through the mouth. The images or pictures obtained will provide useful information to your physician to help in the management of your condition.

This procedure is usually performed on patients with suspected blood clots, or masses in the heart, and patients with heart valve problem or congenital heart condition (a defect that is present at birth). This procedure allows a better visualisation of the structures in the heart.

Transoesophageal Echocardiogram (TEE) - Other Information

What are the risks and complications of TEE?

As this is a semi-invasive procedure, it carries a very small risk of complications similar to that of endoscopy or gastroscopy (endoscopic examination of the food passage or stomach done by the gastroenterologist). Major complications from this test are very rare. Qualified and specially trained doctors will perform this procedure. You may experience a slight sore throat after the procedure.

Please be reassured that major complications are very rare and transoesophageal echocardiography is only performed by qualified and specially trained doctors. The small risk of complications should be weighed against the benefit of diagnostic information that will help guide treatment.

Possible complications for TEE include:

Sore mouth and throat (2%)
Hoarseness (10%)
Airway spasm / difficulty in breathing (<1%)
Bleeding in mouth and throat (<1%)
Dental injury (0.1%)
Heart rhythm abnormality (0.3%)
Injury to oesophagus (0.03%)
Death (0.02%)

As the test is performed on patients with suspected intra-cardiac blood clot or mass, or in patients with impaired heart function, the possible adverse events may also include heart failure, acute myocardial infarction and stroke.

If you have any difficulty in swallowing or any neck problem, please inform the nurse or doctor before the test. Please also highlight to the nurse or doctor if you are taking any blood thinner, such as warfarin or other new oral anticoagulant.

If you are not keen for this procedure, you will need to discuss with your doctor in your next clinic visit. Other form of imaging tests may involve a computed tomography (CT) scan or a magnetic resonance imaging (MRI).

Can I undergo the test if I am not feeling well?

If you are feeling unwell because of fever, running nose or acute illness, you should not proceed with the procedure. Please call the NHCS Call Centre at +65 6704 2000 to reschedule the test.

Preparations before the test

Fasting is required for this test. No food and drinks (including water) at least 6 hours before the test. This is to avoid vomiting which may sometimes occur during the procedure. However, brushing of teeth is allowed.
You may need to stop taking your medications prior to the test. If you are unsure which medication needs to be stopped, please consult your doctor.
Informed consent prior to the procedure is required. For patients below 21 years old, please be accompanied by a parent for consent taking.
An adult should accompany you as you might be sedated for the procedure. No alcoholic drinks, operation of machinery or driving should be carried out within 24 hours after the procedure, due to administration of sedatives.
Please inform the Cardiac Physiologist/Technologist if you have dentures (false teeth) so that they can be removed prior to the procedure.

How is the test done?

Before the procedure starts, a doctor will need you to sign an informed consent and ask you a few routine questions to rule out any contraindications to the procedure, i.e. whether it is advisable for you to undergo the test. Thereafter, an intravenous line will be placed on your hand for any injection of medication. A local anaesthetic will be sprayed into your oral cavity (throat), or you may be asked to swallow an anaesthetic gel in order to minimise any discomfort. You will then be asked to lie on your side and a mouthpiece will be placed between your teeth to prevent you from biting the TEE probe accidentally.

During introduction of the TEE probe, you may experience some mild discomfort in your throat. You may help to minimise this discomfort by cooperating with the doctor, by swallowing when asked to do so. Try to relax and breathe normally. Saliva may accumulate in your mouth; you may let it drip into a small receiver placed next to your mouth.

The test usually takes between 5 and 20 minutes, excluding the preparation time. After the examination, you will be observed for another 10 to 15 minutes before you can go home. You will be observed longer if you have been given sedation. Please inform the doctor if you experience any pain or unusual discomfort in the chest or throat. You may resume eating after the anaesthetic effect in the throat has worn off, which usually takes about half an hour.

Antibiotics may need to be given before the procedure if you have a prosthetic valve or previous history of infection of the heart. Please let the doctor know if you are allergic to any particular antibiotics.

What can I expect after the procedure?

You will be monitored for some time after the procedure if you do not feel well. If the symptoms persist, you may be admitted for observation. If the test turns out to be very abnormal, you may also be admitted for further management after discussion with your doctor.