Aortic valve closure: relation to tissue velocities by Doppler and speckle tracking in normal subjects


    loading  Checking for direct PDF access through Ovid

Abstract

AimsThe aim of this study is to resolve what event in velocity/time curves represents aortic valve closure (AVC) by comparing the timing of AVC visually seen in high frame rate B-mode images with simultaneously recorded apical tissue Doppler imaging (TDI) and speckle-tracking-based velocity/time curves from normal subjects.Methods and resultsA total of 73 recordings from 11 normal subjects were analysed. The acquisition frame rate was equal for both TDI and B-mode (mean 147.5 FPS). The study shows conclusively that the initial negative velocity spike at end-systole occurs before AVC, 26.7 ± 6.2 ms before reference (P < 0.001). The event closest to the reference was the time point of zero velocity after the negative spike, 2.6 ± 8.2 ms before reference. These events are related to the reference in the same way for velocity/time curves by speckle tracking, colour M-mode, and pulsed wave tissue Doppler.ConclusionsAVC in velocity/time curves should be positioned at the end of the negative spike after ejection. Establishing AVC from the correct event in velocity/time curves will ensure more consistent displacement, velocity, strain, and strain rate parameters.

    loading  Loading Related Articles