An echocardiogram is a test that uses sound waves to produce live images of your heart, allowing your doctor to monitor how your heart and its valves are functioning. It is a key test in determining the health of heart muscle, namely after a heart attack. An echocardiogram is painless and does not expose you to radiation.
What to expect
A sonographer (a person who specializes in using ultrasound techniques) will apply gel to your chest. He or she will then briefly put a transducer (a wand-like device) against your chest and move it around.
The transducer sends and receives high-pitched sounds that you probably won’t hear. The echoes from the sound waves are converted into moving pictures of your heart on a screen. You might be asked to lie on your side on an exam table for this test. Some stress echo tests also use dye to improve imaging. The dye is injected into your bloodstream while the test occurs.
This test is used to look at how blood flows through the heart chambers, heart valves, and blood vessels. The movement of the blood reflects sound waves to a transducer. The ultrasound computer then measures the direction and speed of the blood flowing through your heart and blood vessels. Doppler measurements may be displayed in black and white or in color.
During this test, an echocardiogram is done both before and after your heart is stressed either by having you exercise or by injecting a medicine that makes your heart beat harder and faster. A stress echocardiogram is usually done to find out if you might have decreased blood flow to your heart.
What to Expect
During all types of stress testing, a doctor, nurse, or technician will always be with you to closely check your health status. Before you start the “stress” part of a stress test, the nurse will put sticky patches called electrodes on the skin of your chest, arms, and legs. To help an electrode stick to the skin, the nurse may have to shave a patch of hair where the electrode will be attached.
The electrodes will be connected to an EKG (electrocardiogram) machine. This machine records your heart’s electrical activity. It shows how fast your heart is beating and the heart’s rhythm (steady or irregular). An EKG also records the strength and timing of electrical signals as they pass through your heart.
The nurse will put a blood pressure cuff on your arm to check your blood pressure during the stress test. (The cuff will feel tight on your arm when it expands every few minutes.) Also, you might have to breathe into a special tube so the gases you breathe out can be measured.
Next, you’ll exercise on a treadmill or stationary bike. If such exercise poses a problem for you, you might turn a crank with your arms instead. During the test, the exercise level will get harder. You can stop whenever you feel the exercise is too much for you.
If you can’t exercise, medicine might be injected into a vein in your arm or hand. The medicine will increase blood flow through your coronary arteries and make your heart beat fast, as it would during exercise. You can then have the stress test. The medicine may make you flushed and anxious, but the effects go away as soon as the test is over. The medicine also may give you a headache.
While you’re exercising or getting medicine to make your heart work harder, the nurse will ask you how you’re feeling. You should tell him or her if you feel chest pain, short of breath, or dizzy.
The exercise or medicine infusion will continue until you reach a target heart rate, or until you:
- Feel moderate to severe chest pain
- Get too out of breath to continue
- Develop abnormally high or low blood pressure or an arrhythmia (an irregular heartbeat)
- Become dizzy
The nurse will continue to check your heart functions and blood pressure after the test until they return to normal levels. The “stress” part of a stress test (when your heart is working hard) usually lasts about 15 minutes or less. However, there’s prep time before the test and monitoring time afterward. Both extend the total test time to about an hour for a standard stress test, and up to 3 hours or more for some imaging stress tests.
Transesophageal echocardiogram (TEE)
Transesophageal echocardiogram (TEE) is a test that uses sound waves to create high-quality moving pictures of the heart and its blood vessels. TEE is a type of echocardiography (echo). Echo shows the size and shape of the heart and how well the heart chambers and valves are working.
For this test, the probe is passed down the esophagus instead of being moved over the outside of the chest wall. Views of the heart are obtained by moving the transducer to different locations on your chest or abdominal wall. TEE shows clearer pictures of your heart because the probe is located closer to the heart and because the lungs and bones of the chest wall do not block the sound waves produced by the probe.
What to expect
During transesophageal echocardiography (TEE), your doctor will use a probe with a transducer at its tip. The transducer sends sound waves (ultrasound) to the heart. The back of your mouth will be numbed with gel or spray before the probe is put down your throat. You may feel some discomfort as the probe is guided into your esophagus (the passage leading from your mouth to your stomach).
Adults having TEE may get medicine to help them relax during the test. The medicine will be injected into a vein. Your doctor will insert the probe into your mouth or nose. He or she will then gently guide it down your throat into your esophagus. Your esophagus lies directly behind your heart. During this process, your doctor will take care to protect your teeth and mouth from injury.
Your blood pressure, blood oxygen level, and other vital signs will be checked during the test. You may be given oxygen through a tube in your nose. TEE takes less than an hour. However, if you received medicine to help you relax, you might be watched for a few hours after the test for side effects from the medicine.