Quantitative ascending aortic Doppler blood velocity in normal human subjects

Area of Science:

• Cardiovascular Physiology
• Biomedical Engineering
• Medical Imaging

Background:

• Pulsed, range-gated, ultrasonic Doppler velocimetry is a non-invasive technique to assess blood flow.
• Accurate numerical analysis of Doppler signals is crucial for reliable hemodynamic measurements.
• Understanding normal blood flow dynamics in the ascending aorta is essential for diagnosing cardiovascular conditions.

Purpose of the Study:

• To develop and validate digital, microcomputer-based methods for analyzing ultrasonic Doppler blood velocity signals.
• To establish normal hemodynamic values for the ascending aorta in a diverse age group.
• To investigate the pattern of blood flow acceleration during early ejection.

Main Methods:

• Development of digital analysis methods using an Apple II microcomputer.
• Acquisition of Doppler data from the ascending aorta via the suprasternal notch.
• Analysis of signals recorded every 5 milliseconds in subjects aged 3 to 62 years.

Main Results:

• Normal values for peak velocity, velocity integral during systole, and early ejection acceleration were determined.
• Over two-thirds of analyzed beats showed a linear increase in blood velocity during early ejection after an initial rise.
• The duration of constant linear acceleration in the aorta (approximately 50 ms) was independent of subject age or size.

Conclusions:

• The developed digital methods provide a reliable tool for analyzing ultrasonic Doppler blood velocity.
• A consistent pattern of linear acceleration in aortic blood flow during early ejection was observed in normal individuals.
• These findings contribute to a better understanding of normal hemodynamics and may aid in the detection of abnormalities.