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DictionarySeeteeEncyclopediaSeeEchocardiographytransesophageal echocardiography
Transesophageal Echocardiography DefinitionTransesophageal echocardiography is a diagnostic test using an ultrasound device that is passed into the esophagus of the patient to create a clear image of the heart muscle and other parts of the heart. A tube with a device called a transducer is passed down into the patient's throat and into the esophagus (the food tube that connects the mouth to the stomach). The transducer directs ultrasound waves into the heart, and the reflected sound waves picked up by the transducer are translated into an image of the heart.PurposeSince the esophagus is right next to the heart, transesophageal echocardiography provides a very clear picture of the heart. It can provide information on the size of the heart, its pumping strength, and the location and extent of any damage to its tissues. It can detect abnormal tissue growth around the heart valves. It is also good at detecting abnormalities in the pattern of blood flow, such as the backward flow of blood through partly closed heart valves, known as regurgitation or insufficiency. It is especially useful in cases in which conventional echocardiography (a test where the transducer is kept on the patient's chest) cannot offer a good image, such as when the patient is obese or has a thick chest wall. It is useful for monitoring heart function during cardiac surgery and detecting blood clots in the left atrium of the heart.PrecautionsPatients should avoid consuming alcohol for a day or so before the procedure, since alcohol may amplify the effects of the sedative used with the procedure.DescriptionEchocardiography creates an image of the heart using ultra-high-frequency sound waves—sound waves that are much too high in frequency to be heard by the human ear. The technique is very similar to ultrasound scanning commonly used to visualize the fetus during pregnancy.A transesophageal echocardiography examination generally lasts 30-60 minutes. The patient is given a mild sedative and the back of the throat is sprayed with a local anesthetic, in order to suppress the gag reflex. Next, a special viewing tube called an endoscope, containing a tiny transducer, is passed through the mouth and into the esophagus. It is carefully moved until it is positioned directly next to the heart. Essentially a modified microphone, the transducer directs ultrasound waves into the heart, some of which get reflected (or "echoed") back to the transducer. Different tissues and blood all reflect ultrasound waves differently. These sound waves can be translated into a meaningful image of the heart, which is displayed on a monitor or recorded on paper or tape. The transducer may be moved several times during the test to help doctors get a better view of the heart.PreparationThe patient may be given a mild sedative before the procedure, and an anesthetic is sprayed into the back of the throat in order to suppress the gag reflex.AftercareAfter the test, it is important to refrain from eating or drinking until the gag reflex has returned-otherwise, the patient may accidentally inhale some of the food or beverage. If a sedative has been given, patients should not drive or operate heavy machinery for at least 10-12 hours. They should avoid consuming alcohol for a day or so, since alcohol may amplify the effect of the sedative.RisksTransesophageal echocardiography may cause gagging and discomfort when the transducer is passed down into the throat. Patients may also experience sore throat for a few days after the test. In rare cases, the procedure may cause bleeding or perforation of the esophagus or an inflammatory condition known as infective endocarditis. The patient may have an adverse reaction to the sedative or local anesthetic.Normal resultsA normal transesophageal echocardiogram shows a normal heart structure and the normal flow of blood through the heart chambers and heart valves.Abnormal resultsA transesophageal echocardiogram may show a number of abnormalities in the structure and function of the heart, such as thickening of the wall of the heart muscle (especially the left ventricle). Other abnormalities can include blood leaking backward through the heart valves (regurgitation), or blood clots in the left atrium of the heart.ResourcesOrganizationsAmerican Heart Association. 7320 Greenville Ave. Dallas, TX 75231. (214) 373-6300. http://www.americanheart.org.National Heart, Lung and Blood Institute. P.O. Box 30105, Bethesda, MD 20824-0105. (301) 251-1222. http://www.nhlbi.nih.gov.Key termsEndoscope — An instrument used to see and examine the inside of a body cavity or organ.Gag reflex — A normal reflex consisting of elevation of the palate, retraction of the tongue, and contraction of the throat muscles.Regurgitation — Backward flow of blood through a partly closed valve.Transducer — A device that converts electrical signals into ultrasound waves and ultrasound waves back into electrical impulses.Ultrasound — Sound waves at a frequency of 20,000 kHz, often used for diagnostic imaging.trans·esoph·a·ge·al ech·o·car·di·og·ra·phyrecording of the echocardiogram from a transducer swallowed by the patient to predetermined distances in the esophagus and stomach.transesophageal echocardiography Two-dimensional transesophageal color-flow Doppler echocardiography Cardiology An ultrasonographic imaging modality used to examine cardiac structures–valves, chambers and inflow and outflow tracts and function in which a transducer is placed immediately behind the heart in the esophagus and stomach; because there are no interfering air spaces or bone, the image is superior to that obtained with transthoracic echocardiography and is of particular use in evaluating the status of the endocardium–eg, to identify vegetations on the cardiac valves Indications for TEE ID cardiac source of embolism–35%, prosthetic heart valve malfunction–20%, endocarditis–16%, aortic dissection, cardiac tumor, valvular disease, and others, based on a series of 5000 Pts. See Biplane–intraoperative transesophageal echocardiography, Echocardiography. trans·e·soph·a·ge·al echo·car·di·og·ra·phy (tranz'ē-sō-fā'jē-ăl ek'ō-kahr'dē-og'ră-fē) Recording of the echocardiogram from a swallowed transducer. Synonym(s): transoesophageal echocardiography. TRANSESOPHAGEAL ECHOCARDIOGRAPHYtransesophageal echocardiography Abbreviation: TEE A technique for obtaining echocardiographic images in which the ultrasonographic transducer is introduced into the esophagus. TEE is useful in detecting cardiac sources of emboli, prosthetic heart valve malfunction, endocarditis, aortic dissection, cardiac tumors, and valvular and congenital heart disease. See: illustrationSee also: echocardiographyPatient discussion about transesophageal echocardiographyQ. I am scheduled for a TEE and i am very scared. what is exactly going to happen there? I am scheduled for a Transesophageal echocardiogram (TEE) for my heart valve problem and i am very scared. what is exactly going to happen there to me? I understand i need to swallow somthing and I am not sure I'll be able to do it. I have a strong gag reflex. can someone tell me what I can do to reduce the fear? A. During a TEE you will be requested to swallow something that looks like a big chocolate kiss. This is all the swallowing that is involved. It is not fun, and me too have a strong gag reflex. I asked the doctor to let me watch the TEE of the guy that was before me in the line. After I saw how this test is done it was easier for me. (Don't get me wrong, you will want to puke but you will be able to handle this urge) Q. My mother had a chest pain and she was sent for a TEE. When do you need a TEE and when a normal echo is fine? My mother had a chest pain few weeks ago. we were sure its a heart attack and went to the ER. There the doctors did some tests and she was sent for a (trans thoracic echocardiogram) TEE. I want to know when do you need a TEE and when you can do just a normal echocardiogram because the TEE was very painful for her and we want to know if ther was a better way.A. The main difference between TEE and normal echo is that in TEE u put the transducer directly in the esophagus. The transducer is the same and the idea is to put it as close as possible to the heart. As far as I know there are some heart situations the TEE is better for diagnosis that normal echo. Maybe your mom had one of those situations? I can recommend you to ask the ER doctor. he will probably be able to give a better explanation for his choice More discussions about transesophageal echocardiographySee TEE See TEECThesaurusSeeechocardiography |