title: Optimal Acquisition Settings for Speckle Tracking Echocardiography-Derived Strains in Infants: An In Vitro Study.
abstract: The purpose of this study was to investigate the effect of frame rate and probe frequency on the accuracy of speckle tracking echocardiography-derived strain measurements in infants. An infant-sized left ventricle phantom with sonomicrometer crystals was made from polyvinyl alcohol. The examined stroke rates were 60, 120 and 180 strokes per min (SPM). Longitudinal strain and circumferential strain measurements were analyzed from a total of 1860 cine loops. These cine loops were acquired using two pediatric probes of different frequencies at both fundamental and harmonic imaging modes. Both probes were examined at different settings (in total, 30 different frame rate-frequency combinations). At optimal settings, both longitudinal and circumferential strain displayed high accuracy. Frequency settings did not have a consistent effect on accuracy, while low frame rates led to less accurate measurements. We recommend a frame rate/heart ratio >1 frame per second/beats per min, especially for circumferential strain.
authors.affiliation: Bergen Hypertension and Cardiac Dynamics Group, Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: Umael
authors.initials: U
authors.lastname: Khan
authors.affiliation: Bergen Hypertension and Cardiac Dynamics Group, Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: Johannes Just
authors.initials: JJ
authors.lastname: Hjertaas
authors.affiliation: Department of Clinical Science, University of Bergen, Bergen, Norway; Department of Heart Disease, Haukeland University Hospital, Bergen, Norway.
authors.forename: Gottfried
authors.initials: G
authors.lastname: Greve
authors.affiliation: Bergen Hypertension and Cardiac Dynamics Group, Department of Clinical Science, University of Bergen, Bergen, Norway. Electronic address: knut.matre@uib.no.
authors.forename: Knut
authors.initials: K
authors.lastname: Matre
mesh_terms: D004452:Echocardiography / Q000379:methods*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007223:Infant; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D016277:Ventricular Function, Left / Q000502:physiology*
keywords: Echocardiography; Frame rate; Frequency; Infant; In vitro; Left ventricle; Myocardial strain; Phantom; Sonomicrometer; Speckle tracking