Abstract 18663: Reference Values for Left Ventricular Strain by Velocity Vector Imaging in Normal Individuals: Impact of Technical and Clinical Confounders.

Background: Velocity Vector Strain Imaging (VVI-e) is an off-line ultrasound technique which measures e at both the endocardial and epicardial level; importantly, it permits e analysis of DICOM images from machines from different vendors. The aim of this study was to establish reference values for endocardial e and to investigate clinical and technical factors which might impact its measurement. Methods: 124 normal individuals (66% women, 39±13 years, age range 18–77) had echocardiography using commercially available machines. VVI-e was obtained in all three planes (circumferential, radial and longitudinal--C,R,L) by VVI (Tomtec). Technical confounders were considered: image quality, frame rate and machine vendor. We also evaluated effects of: age, gender, heart rate and LV geometry (relative wall thickness-RWT). Results: Technical factors minimally influenced e: frame rate (mean value 60fps, range 26–120fps) did not affect eC, e R, e L(all p=NS); we saw no difference when comparing pts with excellent/goo...