Echocardiography
An echocardiogram (also called an echo) is a type of ultrasound test that uses high-pitched sound waves that are sent through a device called a transducer. The device picks up echoes of the sound waves as they bounce off the different parts of your heart. These echoes are turned into moving pictures of your heart that can be seen on a video screen. Below are different types of echocardiograms.
Transthoracic
Views of the heart are obtained by moving the transducer to different locations on your chest or abdominal wall.
A transthoracic echocardiogram is done to:
● Look for cause of abnormal heart sounds, enlarged heart, chest pains, shortness of breath, or irregular heartbeats.
● Check the thickness and movement of the heart wall.
● Look at the heart valves and check how well they work.
● See how well an artificial heart valve is working.
● Measure the size and shape of the heart's chambers.
● Check the ability of your heart chambers to pump blood.
● Detect a disease that affects the heart muscle and the way it pumps, such as cardiomyopathy.
● Look for blood clots and tumors inside the heart.
● Look for congenital heart defects or to check the effectiveness of previous surgery to repair a congenital heart defect.
● Check how well your heart works after a heart attack.
● Identify the specific cause of heart failure.
● Look for a collection of fluid around the heart or a thickening of the lining around the heart.
Stress
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 (coronary artery disease, or CAD).
A stress echocardiogram may used to:
● Identify and monitor reduced blood flow to heart muscle which is usually more apparent after a form of stress,
such as exercise or medicine.
Doppler
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.
A doppler echocardiogram can be done during a transthoracic echocardiogram (TTE), a transesophageal echocardiogram (TEE), or a stress echocardiogram to:
● Measure the speed at which blood travels through the heart.
● Measure the blood pressure and speed of blood flow through the heart valves.
Transesophageal
For this test, the probe is passed down the esophagus instead of being moved over the outside of the chest 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. A sedative and anesthetic applied to throat are used to make you comfortable during test.
A transesophageal echocardiogram (TEE) may be done to:
● Monitor heart function during surgery.
● Check how well an artificial heart valve works.
● Look for masses or blood clots in the upper left chamber (left atrium) of the heart.
● Identify abnormal blood flow between the chambers of the heart (cardiac shunt).
● Help find out if you have endocarditis.
● Guide procedures done during cardiac catheterization.
● Help find out if you have a tear in the aorta (aortic dissection).