Abstract 16760: Evidence of Variability Of 2D Strain Measures in Human Subjects Referred for Routine Echocardiographic Examination
Purpose: Study of myocardial mechanics is of great importance in a wide range of clinical situations. Recent advances in echocardiographic post-processing methods to quantify myocardial mechanical function have generated great interest. However, there is a wide array of commerical speckle-tracking based software (STE-SW) with varying algorithms. While each has been independently validated against sonomicrometry, comparisons of the STE-SWs on the same set of images would be useful, but lacking. In this study we attempted to compare STE-SWs from 2 commerical sources (STE-SW1 and STE-SW2) to compare left ventricular myocardial velocity (PSV), displacement, and strain%.
Methods: Ninety- nine subjects underwent conventional 2D echocardiography, ensuring that the frame rates were maintained between 60–80 Hz. Three apical images and one parasternal short axis image were post-processed to compute regional velocity, displacement and strain. Bland-Altman plots and regression analysis were performed to assess the agreement between the STE-SWs as regards peak systolic velocity (PSV), displacement, longitudinal, and circumferential strain%. PSV, displacement data are averaged for 4 LV basal segments. The first set of longitudinal strain data represent global longitudinal strain acquired from apical 4 chamber images, while the other from apical 2 chamber projections.
Results: Data are expressed as bias (95% limits of agreements, LOA) along with R2 and p values for bias, regression slope, and ANOVA F statistic. The least bias with least significant difference was noted in global circumferential strain% obtained from the parasternal short axis image, while the greatest discrepancies were found among the displacement measurements (Table).
Conclusions: The data suggest only modest, statistically significant agreement between the STE-SWs, thus emphasizing the need for greater standardization and transparency.
Statistical comparison: STE-SW1 vs. STE-SW2
- © 2010 by American Heart Association, Inc.