What is a Doppler ultrasound?

This noninvasive diagnostic test uses high-frequency sound waves to determine the speed and direction of blood flow in the heart. It is helpful in indicating the presence of a blockage in an artery or vein, or even within the heart. This is a routine part of a typical echocardiogram.

Regular ultrasounds use ultrasonic sound waves to produce images, but cannot determine blood flow. A Doppler ultrasound can measure the heart’s blood flow and evaluate valve movement, helping to detect blockages.

The Doppler probe (ultrasound probe) is placed on the part of the body being examined. Ultrasound waves from the probe travel into the body and bounce off the moving blood cells. These reflected sound waves return to the probe at a different frequency, determining the level of blood flow from the change in sound wave frequency. Doppler ultrasounds provide important information to physicians regarding the status of your heart valves and blood vessels.

In addition to indicating potential artery blockages, Doppler ultrasounds can also be used to diagnose other conditions:

  • Valvular heart disease, including valve stenosis and valve regurgitation
  • Diastolic heart failure (stiff heart)
  • Abnormalities with blood vessels that may have been present from birth
  • Vein abnormalities, including deep vein thrombosis
  • Peripheral arterial disease (PAD) from narrowed arteries in the extremities

What to expect during a Doppler ultrasound

Preparing for your procedure

Your physician will give you instructions to follow before your Doppler ultrasound procedure. It is possible that you might not have to do anything to prepare, or you might need to abstain from food or drink for a specific number of hours before the test. Always ask for instructions when scheduling your Doppler ultrasound.

During your procedure

Patients who undergo Doppler ultrasounds report no pain, but may experience slight discomfort due to the position of the transducer. Doppler ultrasounds usually take an hour, sometimes longer. During the exam, you may hear noises of the blood flow through the heart or blood vessels coming from the ultrasound machine.

After your procedure

You should feel no adverse effects once your Doppler ultrasound is complete. Your physician will review the test results and contact you for any necessary follow up.