All about the transesophageal echocardiogram - TEE
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Updated June 19, 2015.
The transesophageal echocardiogram (TEE) is a test used to assess cardiac structure and function. Like a standard echocardiogram, the TEE uses high-frequency sound waves to produce a real-time, moving image of the heart. Using a TEE instead of a standard echocardiogram can be extremely useful under the right circumstances.
How is TEE performed?
As opposed to the standard echocardiogram, in which the transducer is placed over the chest wall, in TEE the transducer is passed into the esophagus (the swallowing tube) and is positioned directly behind the heart.
If you have a TEE you will be sedated, and your gag reflex will be suppressed by spraying a local anesthetic into the back of your throat. The echo transducer will then be passed through your mouth and throat, and down your esophagus.
Once in position directly behind your heart, the transducer bounces sound waves off your heart (just as in the standard echocardiogram). The returning sound waves will be processed into a moving image of your heart, and projected onto a computer screen for analysis.
What are the advantages of TEE?
There are three major advantages of the TEE over a standard echocardiogram. First, a TEE is useful whenever adequate echo images cannot be obtained by the standard echo techniques. For instance, the standard echo can be difficult to perform in patients whose chest walls are particularly thick, or who have emphysema.) Since the sound waves during TEE do not have to pass through the chest wall or the lungs, good echo images are obtainable in virtually all patients.
Second, TEE can be performed in the operating room during open heart surgery.
Intraoperative TEE is especially useful during valve reconstruction surgery, especially with mitral regurgitation. The echo image can give instant feedback to the surgeon as to the adequacy of the repair.
Third, the TEE can be quite useful in assessing whether a patient with atrial fibrillation has formed blood clots in the left atrium. Demonstrating by TEE that no blood clots are present can make cardioversion of atrial fibrillation significantly safer.
What are the complications of TEE?
The most common problem with the TEE is a certain amount of gagging and throat discomfort during the procedure. Adequate sedation usually minimizes this problem. Patients often have sore throats for a few days after the procedure. Rarely, perforation of the esophagus can occur (a surgical emergency), and occasionally bleeding from the esophagus is seen.
Sources:
Quinones, MA, Douglas, PS, Foster, E, et al. ACC/AHA clinical competence statement on echocardiography: a report of the American College of Cardiology/American Heart Association/American College of Physicians-American Society of Internal Medicine Task Force on Clinical Competence. J Am Coll Cardiol 2003; 41:687.
Daniel, WG, Erbel, R, Kasper, W, et al. Safety of transesophageal echocardiography: A multicenter survey of 10,419 examinations. Circulation 1991; 83:817.