Comprehensive Evaluation of Left Ventricular Strain Using Speckle Tracking Echocardiography in Normal Adults: Comparison of Three-Dimensional and Two-Dimensional Approaches

Objective: The two-dimensional speckle tracking (2DT) method is based on the measurements of strain on two-dimensional (2D) images, ignoring actual three-dimensional (3D) myocardial movements. We sought to investigate the feasibility of the newly developed three-dimensional speckle tracking (3DT) method to assess longitudinal, circumferential, and radial strain values, and then compared the data with those measured by 2DT. Methods: Echocardiographic examinations were performed in 46 volunteers. In the apical 3D volumetric images, 3 vectors of the strains were analyzed in 16 myocardial segments. 2D longitudinal strain was assessed in apical 4-, 3-, and 2-chamber views, and circumferential and radial strains were measured in parasternal short-axis view. Results: The average time for 3D image acquisition and 3D strain analysis by 3DT was significantly shorter than for 2DT. Longitudinal strain value by 3DT was significantly smaller than by 2DT (-17.4% +/- 5.0% vs -19.9% +/- 6.7%, P < .0001), and circumferential strain value by 3DT was significantly larger than by 2DT (-30.1% +/- 7.1% vs -26.3% +/- 6.9%, P < .0001). Intraobserver and interobserver variabilities were 10.1% and 10.9% in 3DT, and 9.9% and 11.1% in 2DT, respectively. Conclusion: 3DT is a simple, feasible, and reproducible method to measure longitudinal, circumferential, and radial strains. The discordant results between 3DT and 2DT may be explained by the 3D cardiac motion that has been ignored in current 2DT. (J Am Soc Echocardiogr 2009; 22: 1025-30.)