Doppler Echocardiography (Vascular Evaluation)

The clinical application of Doppler echocardiography is based on the Doppler shift principle by which sound waves increase or decrease their frequency as the object that produces or reflects them approximates or moves away from a given point. A transducer that acts as a transmitter and receiver is placed so that ultrasound waves are sent parallel to cardiac flow, the red cells reflect these waves and alter the frequency of the ultrasound wave proportionally to the velocity in which they are moving.

With an echocardiograph (heart sonar) the function of the ventricles and valves can be evaluated for abnormalities.