Assessment of Mitral Annular Velocities by Speckle Tracking Echocardiography versus Tissue Doppler Imaging: Validation, Feasibility, and Reproducibility
Background: Mitral annular velocity may be measured angle independently by speckle tracking echocardiography (STE), in contrast with tissue Doppler imaging (TDI). The purpose of the current study was to compare STE and TDI, with respect to 1) the accuracy of velocity measurements in a moving phantom, 2) the feasibility and reproducibility of measurement of mitral annular velocities in a clinical setting, and 3) the estimation of left ventricular filling pressures using mitral annular velocities. Methods: The velocity of a moving phantom, using different angles of insonation, and mitral annular velocities of 80 nonselected patients and 50 healthy volunteers were determined using TDI and STE. A subgroup of 20 patients was studied during right-sided heart catheterization. Results: When the motion direction of the phantom was parallel to the ultrasound beam, both TDI and STE determined velocities accurately. With increasing angle of insonation, TDI-derived velocity decreased, whereas STE-derived velocity remained unchanged. The feasibility of mitral annular velocities measured by TDI and STE was comparable (98% vs 95%, P = not significant). Although for both techniques correlations between measured mitral annular velocities at repeated examinations were good, the test-retest variability of mitral annular velocities by TDI was higher. E/Em ratio by STE correlated better to pulmonary capillary wedge pressure (R2= 0.51, P < .001) compared with E/Em ratio derived from TDI (R2= 0.35, P < .01), although the difference in correlation was not statistically significant because of the limited sample size. Conclusion: Tissue velocities can be accurately determined by STE in a moving phantom and are angle independent, in contrast with TDI measurements. Furthermore, STE is a feasible and better reproducible method for the assessment of mitral annular velocities in a clinical setting.
- Speckle tracking echocardiography
- Mitral annular velocities
- Tissue Doppler imaging