What is an Echocardiogram?
Using ultrasound to examine the heart’s size, shape and motion, this test is used to detect possible abnormal rhythms (arrhythmias) or defects that could cause a stroke. There are several types of echocardiograms:
TTE is a completely noninvasive test that uses reflected
sound waves (echoes) to create images of the beating heart. During the test, a
device called a transducer will be placed on the surface of your chest. The
transducer sends sound waves through the chest wall to the heart, which
reflects the sound waves back to the transducer, creating echoes that are
converted into 2D or 3D images. You will be able to watch your heart beating on
a computer screen as the test is being done.
TTE provides a
wealth of information about the size and shape of the heart, the functioning of
the heart muscle and valves, as well as information about the blood flow
through the heart. This bedside test represents the easiest way to diagnose
valve narrowing (stenosis) or backflow
(regurgitation). Occasionally, TTE is performed in conjunction with a stress
test (typically treadmill exercise). This combination is known as a stress
echocardiogram and helps your physician understand your symptoms better and
choose between major treatment options.
By creating an image of the heart that is more detailed than an X-ray, this noninvasive test is used as a baseline to:
- Evaluate the size of the heart
- Evaluate the heart’s valves and chambers
- Detect abnormalities or presence of heart disease
- Evaluate cardiac function after a heart attack
Patients who are unable to exercise are given dobutamine, an intravenous medication that causes the heart to beat faster, mimicking the effects of exercise.
This more invasive test requires a device called a transducer be inserted down the throat into the esophagus. Because there is no interference from the lungs and chest, these images are clearer than those obtained with the transthoracic echocardiogram (TEE).
During TEE, a very
small transducer is attached to the end of a thin, flexible tube, which is
gently and painlessly guided down the throat and into the esophagus and
stomach. A mild sedative is given intravenously, which requires a short recovery
time at the end of the 15-minute procedure.
TEE is complementary
to TTE and produces high-resolution images of the smallest heart structures.
This test can be performed at the bedside, or during cardiac catheterization or
surgery, guiding the procedures of interventional cardiologists or surgeons
aiming to repair structural heart disease.
During this test, an echocardiogram is performed while the patient uses a treadmill or stationary bike. Performed both before and immediately after exercise, the test can assess how the heart performs under stress. It can reveal parts of the heart that may not be receiving adequate blood or oxygen because of blocked arteries.