ECG Doppler Use: What You Need to Know

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An electrocardiogram (ECG) and Doppler measurement serve distinct purposes in medical diagnostics. An ECG records the electrical signals produced by the heart as it contracts, using electrodes placed on the chest. In contrast, Doppler measurements utilize sound waves to assess blood flow rates and velocities, often visualized in ultrasound imaging where blood flow is color-coded. The Doppler effect refers to the change in frequency of sound waves, which is applied in various technologies, including ultrasound and police radar. However, it is clarified that ECGs do not employ the Doppler effect; they focus solely on electrical impulses from the heart. Understanding these differences is crucial for comprehending how each tool functions in medical contexts.
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I am hoping that someone can tell me how an electrocardio gram uses doppler.
Thanks for any help; cynwood
 
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I'm fairly sure that an electrocardiogram is different from a doppler measurement. The ECG (electrocardiogram) is where they put wires on your chest and record the electrical signals given off as your yeart contracts. A doppler measurement uses sound to montiotor the rate at which blood is flowing. (I'm not sure if there is a more technical name for a doppler measurement, I suspect there is).
 
This is a question that my instructor gave us to find out about and I have found articles that relate the two together, but I am still puzzled to find the how. Other questions that we were given are:
How does ultrasound imaging use doppler?
Find anything else that uses sonar doppler.
The electrocardio-gram seems to be the question that is going to stump me the most though.
I appreciate your trying to help.
Thanks; cynwood :confused:
 
I don't think an ultrasound uses doppler either - its just sonar.
 
I think I'm getting it. The Doppler effect is the change in frequency of sound, light, or radio waves. An electrocardiogram is using doppler to create an illustration of the hearts electrical rhythm. Ultrasound imaging is using it to measure the frequencies of sound waves to determine the location of surfaces within tissues by measuring the time interval between the production of an ultrasonic pulse and the detection of its echo. Now I just need to find other uses for doppler, I think that possibly a police radar gun might be one.
 
russ_watters said:
I don't think an ultrasound uses doppler either - its just sonar.
Ultrasound generates images by measuring the time for ultrasound echoes to return to the proble (very much like SONAR). It uses high frequency sound pulses (in the 1-10 MHz range).

Doppler ultrasound makes use of the Doppler effect to measure blood velocity and flow rates. On an ultrasound display, it's typically shown graphically on the ultrasound image as red flowing away from the probe and blue flowing toward the probe. Many ultrasound units also allow you to listen to the blood flow.

cynwood said:
An electrocardiogram is using doppler to create an illustration of the hearts electrical rhythm. Ultrasound imaging is using it to measure the frequencies of sound waves to determine the location of surfaces within tissues by measuring the time interval between the production of an ultrasonic pulse and the detection of its echo.
Electrocardiograms (ECGs) don't use the doppler effect at all. ECGs simply record the electrical impulses generated by the heart as it contracts during the cardiac cycle. By placing ECG leads at different locations on the chest, you can examine the electrical impulses generated from different regions of the heart.
 
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