Developing an Interface and Investigating Optimal Parameters for Real-Time Intracardiac Subharmonic-Aided Pressure...

Area of Science:

• Cardiovascular Ultrasound
• Medical Imaging Technology
• Biomedical Engineering

Background:

• Accurate intracardiac pressure measurement is vital for cardiovascular disease management.
• Current methods like cardiac catheterization are invasive.
• Ultrasound contrast agents offer potential for noninvasive pressure estimation.

Purpose of the Study:

• To evaluate the real-time functionality of a customized interface for intracardiac subharmonic-aided pressure estimation (SHAPE).
• To determine the optimal parameters for using Definity and Sonazoid microbubbles with SHAPE.
• To establish SHAPE as a noninvasive alternative to invasive pressure measurement techniques.

Main Methods:

• Developed a customized interface for real-time intracardiac SHAPE on a SonixTablet.
• Utilized a Doppler flow phantom to simulate cardiac pressure dynamics.
• Tested Definity and Sonazoid microbubbles at varying frequencies (2.5-4.0 MHz) and pulse shapes (square wave, chirp down).

Main Results:

• The customized interface demonstrated real-time functionality.
• For Definity, optimal performance was achieved with a chirp down pulse at 3.0 MHz (r = -0.77 ± 0.2).
• For Sonazoid, optimal performance was achieved with a square wave pulse at 2.5 MHz (r = -0.72 ± 0.2).

Conclusions:

• The developed interface successfully enables real-time intracardiac SHAPE.
• Specific optimal parameters were identified for Definity and Sonazoid microbubbles.
• This research advances noninvasive intracardiac pressure estimation.