Abstract 8980: Investigating Left Ventricular Torsion with 4-Dimensional Echocardiography
Background: We investigated the relationship between left ventricular (LV) torsion, strain and stroke volume (SV) using a new 4-dimensional (4D) echocardiography strain and mechanics program developed by Siemens.
Methods: We used an in vitro rotation model capable of producing torsion and longitudinal strain in 3 freshly harvested pig hearts, which were secured on a pump phantom in a water bath with the apex fixed and the base rotated 0°, 10° and 20° at SVs of 40, 50, 60 and 70 ml. 4D image loops were obtained on a Siemens Acuson SC2000 ultrasound system using a 4Z1C matrix probe.
Results: As degrees of rotation increased, computed apical and basal rotation increased accordingly. There was no strong correlation between computed rotation and SV. The Siemens 3D mechanics program computed slight degrees of rotation at both the apical and basal levels, even when the phantom control system was set to 0° rotation.
Conclusions: The apparent rotation measured when the rotator was set to 0° supports the hypothesis that rotation is intrinsic and originates from the helical orientation of the myocardial fibers. The 4D program tracked increasing LV rotation extremely accurately in our study.
- © 2012 by American Heart Association, Inc.