Assessment of myocardial deformation in children using Digital Imaging and Communications in Medicine (DICOM) data and vendor independent speckle tracking software

Abstract

Background: Analysis of myocardial deformation from data stored in Digital Imaging and Communications in Medicine format using vendor-independent software may be useful for clinical and research purposes but has not been evaluated in children.

Methods: Grayscale images were prospectively acquired on Vivid 7 (GE Healthcare) and iE33 (Philips Medical Systems) ultrasound systems in 49 children. Digital Imaging and Communications in Medicine and raw data were analyzed using vendor-independent software (Cardiac Performance Analysis, Tomtec Imaging Systems) and vendor-specific software (EchoPAC and QLAB) and results compared. In addition, vendor-independent software using images at 30 frames/sec were compared with images at the higher acquisition frame rate.

Results: Measurement of short-axis radial and circumferential strain (ε) and apical four-chamber longitudinal ε by vendor-independent software was possible in >92% of the children. Intraobserver and interobserver coefficients of variation for global circumferential and longitudinal ε ranged from 7.1% to 15.3% and for radial ε from 23.9% to 30.2%. Strain values were somewhat higher when using GE images at acquisition frame rates compared with ε values using GE images stored at 30 frames/sec. Strain values obtained by vendor-independent software were comparable with those obtained by vendor-specific software for longitudinal ε and higher for circumferential ε. Radial ε values obtained by vendor-independent software were lower than ε values by EchoPAC and higher than ε values by QLAB.

Conclusions: Vendor-independent software-derived ε is feasible and potentially valuable for measuring myocardial deformation in research and in multicenter studies using images from different ultrasound systems, especially for longitudinal deformation. However, a systematic bias for circumferential ε and a high variability in radial ε measurements remain concerns.