Transesophageal echocardiography (TEE) combines the use of a thin, flexible, lighted viewing tube (endoscope) with ultrasound imaging to visualize the heart and nearby structures. The endoscope, which is passed into the mouth and down the esophagus, is used to position a tiny device called a transducer behind the heart. The transducer directs high-frequency sound waves (ultrasound) at the heart; the sound waves that are echoed back from the heart are then electronically converted into real-time images displayed on a viewing monitor. These images may be recorded on film or video and reviewed for abnormalities.

Purpose of the TEE

  • To assess the overall function of the heart’s valves and chambers
  • To evaluate the success of valve surgery
  • To evaluate abnormalities of the left atrium
  • To identify vascular disease in the chest cavity, such as aneurysm, dissection, or atherosclerosis in the aorta (which is a risk factor for stroke)
  • To visualize and evaluate heart conditions, including congenital heart disease; endocarditis (inflammation of the lining membrane of the heart); blood clots; cardiac tumors; and disease of the heart valves or problems with prosthetic valves

Who Performs It

  • A doctor

Special Concerns

  • Because TEE uses high-frequency sound waves and avoids interference from chest wall structures, it can provide higher quality images of the heart than conventional transthoracic echocardiography.
  • People with esophageal abnormalities, such as obstruction (strictures), enlarged blood vessels (varices), or scleroderma; bleeding disorders; previous radiation therapy to the chest; or severe neck arthritis are not candidates for TEE.

Before the TEE

  • Avoid eating or drinking anything for 4 hours before the test.
  • Talk to your doctor about any medicines that you are taking; you may have to stop taking some or all before the test.
  • You will change into a hospital gown before the test.
  • Remove any dentures or oral prostheses immediately before the test.

What You Experience

  • You will lie down on your left side.
  • You are connected to monitors that keep track of your blood pressure and heart rate during the procedure.
  • A sedative medication is injected into a vein in your arm.
  • A topical anesthetic is sprayed on the back of your throat to suppress the gag reflex (however, you may still gag when the endoscope is inserted).
  • A plastic mouthpiece is then inserted to hold your mouth open and to prevent you from biting down on the endoscope.
  • The doctor inserts the endoscope containing the transducer into your mouth and asks you to swallow it. You may have to swallow several times to move it downward to the correct position.
  • The transducer may be moved several times during the test to obtain different views of the heart.
  • The test takes about 15 - 30 minutes in total.

Risks and Complications

  • Ultrasound involves no exposure to radiation.
  • You may have a sore throat for a few days after the test.
  • There is a small risk of bleeding in the esophagus; if this occurs during the test, it will be discontinued. In rare cases, perforation of the esophagus may occur.

After the TEE

  • You will lie down, and your vital signs will be monitored until the sedative wears off.
  • TEE does not necessitate an overnight hospital stay. However, someone should drive you home after the procedure.
  • Do not eat or drink until your gag reflex returns, usually in a few hours. (Touching the back of the throat with a tongue depressor tests for this reflex.)
  • Avoid drinking alcohol for a day or two after the test, since it can increase the sedative effect.


  • The doctor will examine the recorded images and video for any sign of a cardiac or aortic abnormality.
  • If a definitive diagnosis can be made based on these images, appropriate treatment will be initiated.
  • In some cases, more invasive tests, such as cardiac catheterization, may be needed to further evaluate abnormal results.


The Johns Hopkins Consumer Guide to Medical Tests

Simeon Margolis, M.D., Ph.D., Medical Editor

Updated by Remedy Health Media

Publication Review By: the Editorial Staff at

Published: 24 Jan 2012

Last Modified: 13 Jan 2015