An echocardiogram (echo=sound + card=heart + gram=drawing) is an ultrasound test that can
evaluate the structures of the heart, as well as the direction of blood flow within it. Technicians
specially trained in echocardiography produce the images and videos, often using a special probe
or transducer that is placed in various places on the chest wall, to view the heart from different
directions. Cardiologists, or heart specialists, are trained to evaluate these images to assess heart
function and provide a report of the results. The echocardiogram is one of the many tests that can
be done to evaluate heart anatomy and function.

The different types of echocardiograms are:

• Transthoracic echocardiogram (TTE). This is the most common type. Views of the heart are
  obtained by moving the transducer to different locations on your chest or abdominal wall.
• Stress echocardiogram. 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).
• Doppler echocardiogram. 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.
• Transesophageal echocardiogram (TEE). 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 an anesthetic applied to the throat are used to make you comfortable during this test.

Echo can be used as part of a stress test and with an electrocardiogram (EKG or ECG) to help
your doctor learn more about your heart.