Transesophageal echocardiography is also known as TEE, or heart scan with endoscopy. TEE uses a small probe guided into the esophagus while a child is sedated to closely evaluate the heart and blood vessels in the chest.
Echocardiography is a procedure used to assess the heart's function and structures through the use of sound waves. A transducer (similar to a microphone) sends out ultrasonic sound waves at a frequency too high to be heard. When the transducer is placed on the chest at certain locations and angles, the ultrasonic sound waves move through the skin and other body tissues to the heart tissues, where the waves "echo" or bounce off of the heart structures. The transducer picks up the reflected waves and sends them to a computer. The computer displays the echoes as an image of the heart walls and valves.
Transesophageal echocardiography (TEE) uses a probe with a transducer on the end that is guided through the throat and into the esophagus while your child is sedated. The TEE transducer works the same as the one used in a regular echocardiogram. However, doctors can get a clearer image this way because the sound waves do not have to pass through skin, muscle, or bone tissue.
A TEE can utilize one, or more, of several special types of echocardiography:
Doppler echocardiography. The Doppler technique is used to visualize the flow of blood through the heart. The amount of blood pumped with each beat is an indication of heart function. Detecting abnormal blood flow within the heart, such as an abnormal opening between chambers of the heart, a problem with one or more of the heart's valves, or a problem with the heart's walls, can help identify heart defects.
Color Doppler. Color Doppler is an enhanced form of Doppler echocardiography. With color Doppler, different colors are used to designate the direction of blood flow. This simplifies the interpretation of the Doppler technique.
2-D (two-dimensional) echocardiography). This technique is used to "see" the motion of the heart structures. A 2-D echo view appears cone-shaped on the monitor, and the real-time motion of the heart's structures can be observed. This enables the doctor to evaluate the various heart structures at work.
3-D (three-dimensional) echocardiography). This technique captures 3-D views of the heart structures with greater depth than 2-D echo. The live or "real time" images allow for a more accurate assessment of heart function by using measurements taken while the heart is beating. 3-D echo shows enhanced views of the heart's anatomy and can be used to determine the appropriate plan of treatment for a child with heart disease.
TEE is used to evaluate the internal heart structures and path of blood flow in congenital (present at birth) heart defects. TEE is also used during heart surgery to evaluate the effects of surgical intervention to the heart, such as repair of congenital heart defects. In addition, TEE can be used to evaluate the valves of the heart to look for damage or infection.
When echo is indicated, but other circumstances are present that may interfere with the ability to obtain adequate images, a TEE may be more appropriate. Further, certain findings in the heart, such as mitral valve disorders, blood clots or masses, dissection (tear) of the lining of the aorta (the artery which carries oxygenated blood from the heart to the body), and implanted prosthetic (artificial) heart valves may be better visualized and assessed with TEE than with regular echocardiograms. TEE is often done to evaluate for blood clots in the heart prior to cardioversion or ablation procedures done to correct abnormal heart rhythms.
Depending on the results of the TEE, additional tests or procedures may be scheduled to gather further diagnostic information.