Why is an echocardiogram performed?
Your doctor may suggest an echocardiogram if he or she suspects problems with the valves or chambers of your heart or your heart's ability to pump.
Depending on what information your doctor needs, you may have one of the following kinds of echocardiograms:
This is a standard, noninvasive echocardiogram. A technician (sonographer) spreads gel on your chest and then presses a device known as a transducer firmly against your skin, aiming an ultrasound beam through your chest to your heart. The transducer records the sound wave echoes your heart produces. A computer converts the echoes into moving images on a monitor. If your lungs or ribs block the view, a small amount of intravenous dye may be used to improve the images.
If it's difficult to get a clear picture of your heart with a standard echocardiogram, your doctor may recommend a transesophageal echocardiogram. In this procedure, a flexible tube containing a transducer is guided down your throat and into your esophagus, which connects your mouth to your stomach. From there, the transducer can obtain more-detailed images of your heart. Your throat will be numbed, and you'll have medications to help you relax during a transesophageal echocardiogram.
When sound waves bounce off blood cells moving through your heart and blood vessels, they change pitch. These changes (Doppler signals) can help your doctor measure the speed and direction of the blood flow in your heart. Doppler techniques are used in most transthoracic and transesophageal echocardiograms, and can check blood flow problems and blood pressures in the arteries of your heart that traditional ultrasound might not detect.
Some heart problems — particularly those involving the coronary arteries that supply blood to your heart muscle — occur only during physical activity. For a stress echocardiogram, ultrasound images of your heart are taken before and immediately after walking on a treadmill or riding a stationary bike. If you're unable to exercise, you may get an injection of a medication to make your heart work as hard as if you were exercising.