Transoesophageal echocardiography (TOE)

TOE is a test used to assess the function of the heart and heart valves. It works using ultrasound waves (the same technology as scans performed on pregnant women to look at the foetus). The examination allows us to scan the heart using ultrasound waves and produce moving pictures of the heart as it beats as well as showing the blood flowing through the heart valves.

You may have already had a Transthoracic Echocardiogram (TTE) performed. This is where an echocardiography technician places a transducer (a special ultrasound probe) on your chest after applying some gel. The transducer is moved around on your chest to get the preferred images. During the scan you may hear whooshing noises; this represents the blood flowing in your heart.

TOE is similar to TTE in that we use a transducer and ultrasound waves to produce the images. The difference is where the transducer is placed. For a TTE, the transducer is placed on your chest. To perform TOE, you are asked to swallow the transducer so that is sits inside your gullet (oesophagus), behind the heart. This reduces interference and produces a much clearer and more detailed image of the heart.

The images of the beating heart are transmitted to a monitor (screen) for the doctor to see if the heart muscle is contracting properly and the heart valves are working normally. Other heart problems may also be identified.

As already stated, TOE involves swallowing the transducer so that it sits inside your gullet. You will be asked to open your mouth wide; the doctor will then spray local anaesthetic to the back of your throat to numb the area. The doctor or nurse may also give you some sedation. A small mouth guard will be put in place to protect your teeth and the equipment. Following this the TOE transducer (a thin flexible tube) will be passed through your mouth, down into your throat.

Your test will be performed as a day case at either Cheltenham General Hospital or Gloucestershire Royal Hospital. The location will be given to you in your appointment letter.

Do not eat or drink anything from midnight of the night before your appointment, you may have a sip of water to take any tablets in the morning. If you are currently taking warfarin, or one of the other oral anticoagulants, please let the nurse know when you arrive at hospital.

If you have diabetes, please do not take any of your diabetic medication (insulin or tablets) on the morning of your procedure. Bring your medication with you and inform the nurses on admission that you are diabetic. Your medication will be re-started after the procedure.

When you come into hospital for the TOE, a nurse or doctor will discuss the procedure with you. You will then be asked to sign a consent form. This is to make sure you understand what the procedure involves.

If you have any allergies or have had bad reactions to any medication or other tests, please let the nurse and/or doctor know.

Please make sure that you tell the staff if you have:

• had surgery to the throat or neck.
• indigestion type symptoms.
• difficulty in swallowing food.
• ever coughed or vomited blood.
• any false teeth, loose teeth, crowns or caps.

This is because it may be necessary (at another time) to examine your throat, oesophagus and stomach more closely to check that there are no problems.

Please bring the following:

• A list of any medication you are taking.
• Your reading glasses.
• A dressing gown.
• A book or magazine.

Please do not wear any jewellery, make-up or nail varnish for this appointment. Do not bring any valuables with you, as we cannot take responsibility for any losses.

• A nurse or doctor will place a cannula (thin tube/drip) in your arm.
• A probe will be placed on your finger to measure your pulse and oxygen levels.
• A cuff will be placed on your arm to measure your blood pressure.
• You will be given a small amount of oxygen to breathe via prongs up the nose.
• Local anaesthetic will be sprayed to the back of your throat to numb the area.
• You will be asked to lie on your left side on a trolley and you will be made as comfortable as possible. A nurse will stay with you and reassure you throughout the test.
• Sedation may be given at this point through the cannula (drip).
• To protect your teeth and the scope, a small plastic mouth guard will be put into your mouth and secured around your head with a strap. This will not interfere with your breathing.
• The probe will be passed into your mouth, over your tongue and the doctor will ask you to swallow. This will help the probe pass smoothly into your gullet.
• The examination usually takes between 10 and 30 minutes.
• When the examination is finished, the scope is removed quickly and easily.

After the examination, you will return to a recovery area. A nurse will check on you regularly. Because of the local anaesthetic throat spray, you will have to wait until your swallowing reflex is back to normal. You will not be given anything to eat or drink for an hour after the procedure. The nurse will then decide when you are ready to go home.

TOE is a safe procedure and complications are rare. These include perforation or a tear to the wall of the oesophagus and bleeding. There is also an increased risk of damage to crowned teeth or dental bridgework. Because of the probe being passed down your throat, you may have a sore throat following the procedure. You will be closely monitored throughout and if there is any cause for concern, the test will be stopped immediately.

• For the rest of the day, drink only cold/warm fluids (not hot), and eat only a light meal following the examination.
• If you have not received sedation, you will be able to go home within about 1¼ hours after your appointment time.
• If you have been given sedation, you will be able to go home within about 2½ hours. However it is essential that someone comes to pick you up and that you have someone to stay with you overnight.
• If you have had sedation, it is also important to rest and relax for the rest of the day. You must not drive, sign legal documents, operate machinery or drink alcohol for 24 hours following sedation. We also advise you not to return to work for 24 hours from the time of sedation.

The results of your examination will usually be sent to the doctor who referred you for this test. Your GP may also receive a copy. You may be given the results after the test but if you have had sedation, you may not remember them fully.

If you have any questions or worries about your examination, please contact the Cardiology Department.

Cardiology Department

Gloucestershire Royal Hospital Tel: 0300 422 6542

Monday to Friday, 9:00 am to 4:00 pm

Cheltenham General Hospital Tel: 0300 422 4461

Monday to Friday, 9:30 am to 3:00 pm