Persistence of Albunex (ALB) Ultrasound Contrast Agent – Invitro Study of the Effects of Pressure and Acoustic Power on Particle-Size, and the Duration of Contrast and Doppler Enhancement
LV contrast intensity after intravenous ALB injection varies with the cardiac cycle, raising questions about the pressure related stability of the particle. We explored pressure stability and the influence of acoustic power on ALB effect in an in-vitro pulsatile model at receiving chamber (RC) pressures between 10-160 mmHg. Ultrasound imaging was performed at 5MHz along with 3.5MHz color Doppler at maximal and minimal levels of acoustic power output on a VingMed CFM scanner. We also studied the effects of static RC pressure on particle size and survival using a new phase shift laser Doppler device (Dantec). An inverse relationship existed between RC mean pressure and the duration of both echo and Doppler enhancement (r-0.95 and r-0.94, respectively). At 40-80 mmHg RC pressures, contrast persistence determinations were shorter at the higher compared to the lower acoustic power output (p- <0.05). On laser Doppler study, particle size decreased as RC pressure increased prior to particle disruption. Higher RC pressures com· press the ALB micro particle and decrease its half-life. Increased acoustic output may also shorten ALB effect.
© 1990 American Heart Association.
Published - Gharib_1990p95.pdf