An echocardiogram involves the use of high-pitched sound waves to produce moving images of the heart, explains WebMD. During the test, a transducer sends sound waves and receives echoes of the waves that reflect off various parts of the heart. The doctor views the live images on a video monitor.
During a transthoracic echocardiogram, the doctor acquires pictures of the heart by rubbing the transducer on different areas of the chest or abdominal wall, states WebMD. A stress echocardiogram requires subjecting a patient's heart to stress by letting the patient exercise or injecting a drug that speeds the heart beat. Doctors performs an echocardiogram before and after stressing the heart. This type of echocardiogram helps doctors find out if a patient suffers coronary artery disease, in which blood flow to the heart is reduced.
A doppler echocardiogram involves measuring the speed and direction of blood flow through the heart and blood vessels using an ultrasound computer, according to WebMD. This test allows doctors to evaluate the blood circulation in the blood vessels, heart valves and heart chambers.
During a transesophageal echocardiogram, the doctor inserts a probe into the esophagus to obtain clearer images of the heart, notes WebMD. The probe's close position to the heart and the lack of obstructions to the sound waves enable doctors to get better pictures of the heart.