How does it work?
Doppler ultrasound uses high–frequency sound waves, which are passed through the body. The sound waves are delivered through a wand–like device called a Transducer. When the transducer is placed on the skin, tissues in your body, especially blood, absorb the sound waves. The absorbed sound waves become echoes, which are sent back to the transducer and converted to an image on a television monitor.
What to expect
No special preparation is needed before you have a cardiac ultrasound.
During the test, you will lie on an examination table. A thick gel will be put on your skin, over the area to be examined. The gel may feel cold, but it does not harm your skin. An ultrasound technician will then place the transducer against your skin. The transducer sends and receives the high–frequency sound waves. The sound waves return to the transducer as echoes, which are converted into images on a television monitor. Those images are recorded and given to a radiologist to read.
An ultrasound takes about 45 minutes to perform. You should not have any discomfort, but you may be asked to hold your breath several times during the test. Ultrasound is a very safe test, and there are no harmful side effects. In fact, the amount of energy used for the test is so low that it cannot cause any damage to your body’s tissues.