Velocity estimation of naturally occurring mechanical waves in the left ventricle in healthy persons

The propagation velocities of three naturally occurring mechanical waves in the left ventricle were investigated for this study for seven healthy volunteers. Ultrasound images were acquired at high frame rates and analyzed with a novel signal processing method called clutter filter wave imaging, designed to detect mechanical waves propagating in tissue. Six ventricular walls were investigated per subject and the velocities were compared wall by wall, and for increasing frame rates. The aim of this study was to contribute to measurements of velocities of naturally occurring mechanical waves in healthy persons, to possibly be able to use these velocities to distinguish between healthy and pathologic cardiac tissue. Additionally, we wanted to investigate changes in the velocities based on acquisition frame rates and on locations in the left ventricle. The study found that the lower frame rate intervals led to fewer exclusions of estimates due to quality and lower ranges of average velocities between subjects. No pattern was found for increased or decreased velocities in different parts of the LV.