Three-dimensional speckle-tracking imaging for left ventricular rotation measurement: an in vitro validation study.
OBJECTIVE
Left ventricular (LV) twist is manifested in oppositely directed apical and basal rotation. We studied a new 3-dimensional (3D) echocardiography program (wall motion tracking; Toshiba America Medical Systems, Inc, Tustin, CA) for left ventricular rotation.


METHODS
We used a rotation model with a variable-speed motor to rotate hearts in a water bath. We studied 10 freshly harvested pig hearts, which were mounted on the rotary actuator of our twist phantom with the heart base rotating and the apex held fixed to avoid translational motion, at rotations of 0 degrees , 15 degrees , 20 degrees , and 25 degrees . Full-volume 3D image loops were acquired on a Toshiba Aplio Artida ultrasound system at a maximized frame rate.


RESULTS
As the actual heart rotation increased, computed segmental and global rotation also increased accordingly, with the measured rotations of the basal and middle segments greater than that of the apex (both P < .001). Segmental and global rotation at all 3 levels correlated well with the actual rotation (base: r = 0.93; middle: r = 0.92; apex: r = 0.82; global: r = 0.95; all P < .001).


CONCLUSIONS
The new 3D program tracked LV rotation accurately.
Zhou
Zhiwen
Z
Shanghai 10th People's Hospital, affiliated with Tongji University, Shanghai, China.
Ashraf
Muhammad
M
Hu
Dayi
D
Dai
Xiaonan
X
Xu
Yawei
Y
Kenny
Bill
B
Cameron
Berkley
B
Nguyen
Thuan
T
Xiong
Li
L
Sahn
David J
DJ
D000818:Animals; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D066298:In Vitro Techniques; D016014:Linear Models; D015203:Reproducibility of Results; D012399:Rotation; D013552:Swine