Abstract 2917: Assessment of Left Ventricular Rotation and Torsion with Two-dimensional Speckle Tracking Echocardiography
Background- Speckle tracking echocardiography(STE) has a unique feature of angle-independency and thus may provide a powerful means of assessing left ventricular torsion (LVtor). The aims of the present study were 1) to assess the feasibility of STE in the measurement of LVtor, and 2) the relationship of LVtor with age and conventional echo parameters.
Methods & Results- We consecutively recruited 160 healthy volunteers. Apical and basal short axis rotations were assessed with STE. LVtor was defined as the net-difference between rotation angles in the two short-axis planes normalized for LV longitudinal length. Reliable LVtor measurement was possible only in 56 subjects(35%). This low feasibility was mainly due to failure to obtain reliable basal rotation values. In 56 subjects who were finally enrolled in the present study, a significant correlation was found between LV ejection fraction and LVtor(r = 0.56,p < 0.001) and this correlation is attributed to apical(r = 0.47,p < 0.001) but not to basal rotation(p = 0.14)(Figure⇓). There was no change in LVtor with aging. However, initial counterclockwise motion(r = −0.51,p = 0.001) and its interval(r = −0.44,p = 0.001) in the basal rotation gradually decreased with aging, and correlated with mitral inflow parameters(Figure⇓). In contrast, such correlations were not found for initial clockwise motion and its interval in the apical rotation.
Conclusions- Currently, STE has limited feasibility in the measurement of LVtor. There was no age-related change in LVtor. In LV rotations, basal rotation was affected by the age-related changes in the LV early diastolic filling, while apical rotation is mainly related to LV systolic function.