title: In-vivo validation of a new clinical tool to quantify three-dimensional myocardial strain using ultrasound.
abstract: Three-dimensional (3D) strain analysis based on real-time 3-D echocardiography (RT3DE) has emerged as a novel technique to quantify regional myocardial function. The goal of this study was to evaluate accuracy of a novel model-based 3D tracking tool (eSie Volume Mechanics, Siemens Ultrasound, Mountain View, CA, USA) using sonomicrometry as an independent measure of cardiac deformation. Thirteen sheep were instrumented with microcrystals sutured to the epi- and endocardium of the inferolateral left ventricular wall to trace myocardial deformation along its three directional axes of motion. Paired acquisitions of RT3DE and sonomicrometry were made at baseline, during inotropic modulation and during myocardial ischemia. Accuracy of 3D strain measurements was quantified and expressed as level of agreement with sonomicrometry using linear regression and Bland-Altman analysis. Correlations between 3D strain analysis and sonomicrometry were good for longitudinal and circumferential strain components (r = 0.78 and r = 0.71) but poor for radial strain (r = 0.30). Accordingly, agreement (bias ± 2SD) was -5 ± 6 % for longitudinal, -5 ± 7 % for circumferential, and 15 ± 19 % for radial strain. Intra-observer variability was low for all components (intra-class correlation coefficients (ICC) of respectively 0.89, 0.88 and 0.95) while inter-observer variability was higher, in particular for radial strain (ICC = 0.41). The present study shows that 3D strain analysis provided good estimates of circumferential and longitudinal strain, while estimates of radial strain were less accurate between observers.
authors.affiliation: Department of Anesthesiology, Ghent University Hospital, De Pintelaan 185, 9000, Ghent, Belgium. stefaan.bouchez@ugent.be.
authors.forename: S
authors.initials: S
authors.lastname: Bouchez
authors.affiliation: Laboratory on Cardiovascular Imaging and Dynamics, KU Leuven, Leuven, Belgium.
authors.forename: B
authors.identifier: http://orcid.org/0000-0001-7420-3220
authors.initials: B
authors.lastname: Heyde
authors.affiliation: Laboratory on Cardiovascular Imaging and Dynamics, KU Leuven, Leuven, Belgium.
authors.forename: D
authors.initials: D
authors.lastname: Barbosa
authors.affiliation: Department of Anesthesiology, Ghent University Hospital, De Pintelaan 185, 9000, Ghent, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Vandenheuvel
authors.affiliation: Ultrasound Division, Siemens Medical Solutions, Mountain View, CA, USA.
authors.forename: H
authors.initials: H
authors.lastname: Houle
authors.affiliation: Ultrasound Division, Siemens Medical Solutions, Mountain View, CA, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Laboratory on Cardiovascular Imaging and Dynamics, KU Leuven, Leuven, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: D'hooge
authors.affiliation: Department of Anesthesiology, Ghent University Hospital, De Pintelaan 185, 9000, Ghent, Belgium.
authors.forename: P F
authors.initials: PF
authors.lastname: Wouters
mesh_terms: D058671:Adrenergic beta-1 Receptor Antagonists / Q000494:pharmacology; D000818:Animals; D004195:Disease Models, Animal; D019560:Echocardiography, Three-Dimensional; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000503:physiopathology; D007090:Image Interpretation, Computer-Assisted; D016014:Linear Models; D008955:Models, Cardiovascular; D009200:Myocardial Contraction / Q000187:drug effects; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging* / Q000503:physiopathology; D015588:Observer Variation; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012756:Sheep; D013314:Stress, Mechanical; D016277:Ventricular Function, Left / Q000187:drug effects; D017725:Ventricular Pressure
chemical_list: D058671:Adrenergic beta-1 Receptor Antagonists
keywords: Cardiology; In-vivo validation; Sonomicrometry; Strain; Ultrasound imaging; Ventricular mechanics