Optimization of Microbubble Concentration and Acoustic Pressure for Left Ventricular High-Frame-Rate EchoPIV in Patients

• Published in: IEEE transactions on ultrasonics, ferroelectrics, and frequency control Vol. 68; no. 7; pp. 2432 - 2443
• Main Authors: Voorneveld, Jason, Keijzer, Lana B. H., Strachinaru, Mihai, Bowen, Daniel J., Mutluer, Ferit Onur, van der Steen, Antonius F. W., Cate, Folkert J. Ten, de Jong, Nico, Vos, Hendrik J., van den Bosch, Annemien E., Bosch, Johan G.
• Format: Journal Article
• Language: English
• Published: United States IEEE 01.07.2021; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Acoustics; Amplitudes; Aorta; Blood flow; Blood flow imaging; Contrast agents; contrast-enhanced ultrasound (CEUS); Doppler effect; echo-particle image velocimetry (echoPIV); echocardiography; Heart; heart failure; high-frame-rate (HFR) imaging; Image contrast; Image quality; Optimization; Particle image velocimetry; Probes; ultrafast ultrasound imaging; Ultrasonic imaging; ultrasound velocimetry; vector flow imaging (VFI); Velocity measurement; Voltage measurement
• ISSN: 0885-3010; 1525-8955
• DOI: 10.1109/TUFFC.2021.3066082

High-frame-rate (HFR) echo-particle image velocimetry (echoPIV) is a promising tool for measuring intracardiac blood flow dynamics. In this study, we investigate the optimal ultrasound contrast agent (UCA: SonoVue) infusion rate and acoustic output to use for HFR echoPIV (PRF = 4900 Hz) in the left ventricle (LV) of patients. Three infusion rates (0.3, 0.6, and 1.2 ml/min) and five acoustic output amplitudes (by varying transmit voltage: 5, 10, 15, 20, and 30 V-corresponding to mechanical indices of 0.01, 0.02, 0.03, 0.04, and 0.06 at 60-mm depth) were tested in 20 patients admitted for symptoms of heart failure. We assess the accuracy of HFR echoPIV against pulsed-wave Doppler acquisitions obtained for mitral inflow and aortic outflow. In terms of image quality, the 1.2-ml/min infusion rate provided the highest contrast-to-background ratio (CBR) (3-dB improvement over 0.3 ml/min). The highest acoustic output tested resulted in the lowest CBR. Increased acoustic output also resulted in increased microbubble disruption. For the echoPIV results, the 1.2-ml/min infusion rate provided the best vector quality and accuracy; mid-range acoustic outputs (corresponding to 15-20-V transmit voltages) provided the best agreement with the pulsed-wave Doppler. Overall, the highest infusion rate (1.2 ml/min) and mid-range acoustic output amplitudes provided the best image quality and echoPIV results.