[Doppler tissue imaging of pre-ejection left ventricular wall dynamics in normal subjects]

Area of Science:

• Cardiology
• Medical Imaging
• Physiology

Background:

• Pre-ejectional left ventricular wall motion is clinically assessed via angiography.
• Intramyocardial wall velocities from cardiac contraction can be measured using Doppler tissue imaging.

Purpose of the Study:

• To detect pre-ejectional wall motion using Doppler tissue imaging.
• To analyze the sequence of this motion.

Main Methods:

• M-mode imaging with simultaneous septal and posterior wall visualization in 11 healthy subjects.
• Velocity analysis between the Q wave and ejection onset using digitized images with automatic velocity extraction.
• Comparison of pre-ejectional periods between Doppler tissue imaging and conventional Doppler.

Main Results:

• Observed oscillatory patterns with alternating colors in adjacent wall bands and mirror images between walls.
• Significant differences in mean and peak velocities between walls and specific bands (p < 0.001 to p < 0.02).
• Band 2 duration, indicating motion towards the ventricular center, exceeded adjacent bands (p < 0.001 to p < 0.02).
• High correlation coefficients for total pre-ejectional period duration between Doppler tissue imaging and conventional Doppler (r=0.83 for septum, r=0.76 for posterior wall).

Conclusions:

• Regional pre-ejectional wall motion can be reliably recorded using Doppler tissue imaging.
• During isovolumic contraction, both septal and posterior walls exhibit motion predominantly towards the left ventricular center.
• This observed wall motion precedes the rise in ventricular pressure, aligning with prior angiographic findings.