Direct Ultrasound Measurement of Longitudinal, Circumferential, and Radial Strain Using 2‐Dimensional Strain Imaging in Normal Adults

Current noninvasive techniques used to evaluate left ventricular systolic function are limited by dependence on the angle of insonation (tissue Doppler imaging/TDI) or limited by availability (MRI tagging). We utilized 2‐dimensional speckle strain (ε) imaging (1) to establish normal values for all three ε vectors; (2) to compare circumferential ε values with circumferential shortening (midwall fractional shortening (FS mw ); (3) to examine the relationship between left ventricular ε and wall stress; and (4) to compare 2D echocardiographic characteristics by gender. Echocardiography was performed in 60 normal subjects (mean 39 ± 15 years). Small, but significant regional heterogeneity was seen in circumferential ε, but not in radial or longitudinal ε. We found an inverse correlation between circumferential ε and stress (r =−0.29, p<0.05) as well as longitudinal ε and stress (r =−0.11, P < 0.05), though the relationships were not close. We also observed a linear relationship between mean circumferential ε and FS mw (r = 0.29, P < 0.05). In conclusion, (1) 2‐dimensional ε imaging permits measurement of regional systolic ε values in the majority of normal individuals; (2) ε values furnished by this method obey expected stress‐shortening relationships; (3) systolic ε displays minor regional heterogeneity in the circumferential direction; (4) for the first time, a close relationship between FS mw and mean circumferential ε was demonstrated; and (5) there are minor gender‐related differences in LV geometry and function.