Echocardiography uses sound waves to produce images of the heart and heart function. Depending on the type of echocardiography used, doctors can see how blood is flowing through the heart and study the size, shape, and movement of heart muscle, heart valves, and arteries.

How It Works

Echocardiography uses high-frequency sound waves (also called ultrasound) that are reflected off of the heart and recorded to provide moving pictures. The sound waves are sent through the body with a device called a transducer. The sound waves bounce off of the heart and return to the transducer as echoes. The echoes are converted into images on a television monitor to produce a one-, two-, or three-dimensional picture of the heart.

-One-dimensional or M-mode echocardiography is one beam of ultrasound directed toward the heart. Doctors most often use M-mode echocardiography to see just the left side (or main pumping chamber) of the heart.

-Two-dimensional echocardiography, one of the most important diagnostic tools for doctors, produces a broader moving picture of the heart.

-Three-dimensional echocardiography takes into account the specific shape of the heart rather than assuming the geometrical shape, producing more accurate data measurements. It is also better for visualizing the right ventricle and for measuring abnormal muscle function in the heart.

– Doppler echocardiography measures blood flowing through the arteries and shows the pattern of flow through the heart.

What To Expect

No special preparation is needed before an echocardiogram. During the test, the patient lies on an examination table. A technician connects the patient to an electrocardiogram (EKG) machine to monitor heart rhythm during the test. Next, the technician applies a thick gel to the patient’s chest. The gel may feel cold; it does not harm the skin. Then the technician uses the transducer to send and receive the sound waves. The transducer is placed directly on the left side of the chest above the heart. The technician presses firmly as he or she moves the transducer across the chest. The patient may be asked to breathe in or out or to briefly hold his or her breath during the test. For most of the test, the patient just lies still. An echocardiogram may take up to 45 minutes to perform, and the patient should not have any pain or discomfort during the test. The images are recorded through the chest, and this type of echocardiogram is called a transthoracic echo.

Transesophageal Echocardiography (TEE)

If a more detailed image is needed, a transesophageal echocardiogram may be ordered. Instead of placing the transducer on the patient’s chest, it is inserted into the patients throat and down into the esophagus. The proximity of the esophagus to the heart allows for detailed images of the heart valves and extremely accurate pictures of how the blood is moving through the heart chambers.


Texas Heart Institute