A composite high-frame-rate system for clinical cardiovascular imaging

Area of Science:

• Cardiovascular Imaging
• Medical Ultrasound Technology
• Biomedical Engineering

Background:

• High frame-rate ultrasound is essential for advanced cardiovascular imaging like myocardial elastography, pulse wave imaging (PWI), and electromechanical wave imaging (EWI).
• Standard clinical ultrasound systems face limitations in achieving the necessary frame rates for these novel techniques.

Purpose of the Study:

• To develop an automated multi-sector ultrasound imaging method using retrospective electrocardiogram (ECG) gating.
• To overcome frame-rate limitations and achieve high spatial and temporal resolution for cardiovascular imaging.

Main Methods:

• Developed an automated method for multi-sector ultrasound imaging on an open architecture clinical system.
• Utilized retrospective ECG gating to combine data from multiple sectors for full-view reconstruction.
• Acquired simultaneous ECG and ultrasound RF signals, reconstructing composite frames in RF- and B-mode.
• Employed RF-based speckle tracking to estimate axial displacement and image wave propagation.

Main Results:

• Achieved high spatial resolution (64 beam density) and high temporal resolution (481 Hz frame rate) at an imaging depth up to 11 cm.
• Demonstrated full-view, in vivo imaging of the left ventricle and abdominal aorta in healthy subjects.
• Successfully imaged electromechanical wave and pulse wave propagation, identifying potential indicators of cardiovascular disease.

Conclusions:

• The developed clinical system enables high frame-rate, full-view cardiovascular imaging.
• This technique enhances quantitative, noninvasive diagnosis of conditions such as myocardial ischemia, arrhythmia, and atherosclerosis.
• The method expands applications in cardiovascular elasticity imaging for early disease detection.