RT Journal Article
SR Electronic
T1 Image Quality Causes Substantial Bias in Three-Dimensional Speckle-Tracking Echocardiography Measures
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 500777
DO 10.1101/500777
A1 Lamia Al Saikhan
A1 Chloe Park
A1 Alun Hughes
YR 2018
UL http://biorxiv.org/content/early/2018/12/18/500777.abstract
AB BACKGROUND Three-dimensional speckle-tracking echocardiography (3D-STE) is increasingly used to assess left ventricular (LV) mechanics but the quantitative effect of image quality on measurements is not known.OBJECTIVES To assess the impact of image quality on 3D-STE derived LV indices.METHODS Echocardiography was performed in two groups of 18 healthy participants. In the first study, optimal and intentionally poor-quality images were acquired. In the second study, a sheet of ultrasound-attenuating material (neoprene rubber) of three different thicknesses (2, 3 and 4 mm) was used to mimic mildly, moderately and severely impaired image quality respectively.RESULTS In both studies sub-optimal image quality resulted in a systematic underestimation bias in all LV deformation and rotational indices. LV ejection fraction and volumes were also consistently underestimated. The extent of the bias was proportional to the impairment in image quality (i.e. the poorer the image quality the larger the bias). Reproducibility was also less good for sub-optimal images, although LV volumes and ejection fraction showed excellent reproducibility irrespective of image quality.CONCLUSIONS Sub-optimal image quality introduces a substantial systematic bias and impairs the reproducibility of 3D-STE. Bias related to image quality might have important clinical implications since its magnitude is similar to that reported in association with disease and may confound associations between disease and LV mechanics.CONDENSED ABSTRACT Three-dimensional speckle-tracking echocardiography (3D-STE) is increasingly used in clinical practice. We assessed the impact of sub-optimal image quality on left ventricular (LV) deformation indices either by poor echocardiographic technique or by impairing ultrasound propagation using a neoprene sheet. Sub-optimal image quality introduces a substantial systematic bias that increases with poorer image quality. Bias due to image quality might have important clinical implications since its magnitude is similar to that reported in association with disease.ABBREVIATIONSCScircumferential strainGCSglobal circumferential strainGLSglobal longitudinal strainICCintraclass correlation coefficientLSlongitudinal strainLVleft ventricularLVEFleft ventricular ejection fractionPTSprinciple tangential strainRSradial strainSTEspeckle-tracking echocardiography3DEthree-dimensional echocardiography