Abstract 13148: Timing, Not Magnitude, of Peak Systolic Strain is Similar Across Speckle Tracking Platforms: A Comparison of 2D Strain with Velocity Vector Imaging
Background: Speckle tracking echocardiography (STE) provides novel insight into both global and regional systolic and diastolic function. There are both vendor-dependent (2D strain-GE Healthcare-2DS) and vendor-independent (Cardiac Performance Analysis-CPA-TomTec Imaging Systems-VVI) analysis algorithms that are available. Accordingly our aim was (1) to establish reference values for strain (ε) and systolic synchrony and (2) to determine whether the two different STE methods provide similar data.
Methods: 27 consecutive normal subjects were studied (average age 47 years, 72% female). DICOM data were analyzed with EchoPac (GE) and CPA (TomTec) software, offline. The peak principal strains, longitudinal (εl), circumferential (εc), and radial (εr) were derived by both 2DS and VVI STE. We also computed time to peak maximal ε (TPkε) for all ε values, and between corresponding wall segments.
Results: (see Table)ε values obtained by VVI were comparable to those obtained by 2DS for εl and higher for εc, while εr values obtained by VVI were lower. TPkε values for all three principal ε were comparable within 10ms, and correlated closely between 2DS and VVI: TPkεl r = 0.57 p < 0.01, TPkεr r = 0.47 p < 0.02, TPkεc r = 0.77 p < 0.01. SD values were computed for TPk as a parameter of dyssynchrony (Table).
Conclusions: In establishing normal values for the 3 principal ε and systolic synchrony by two STE methods, we have found: (1) there is remarkable synchrony in the normal LV; (2) the two STE methods give congruent values for TPkε, though the lower SD for 2DS makes it a more appealing method for the assessment of systolic synchrony; (3) peak ε values are not interchangeable; VVI methods show higher values for εl and εc, and lower values for εr.
- © 2011 by American Heart Association, Inc.