Clinical Significance of Left Ventricular Torsional Parameters during Supine Bicycle Cardiopulmonary Exercise Echocardiography

Abstract

Introduction The Left ventricular (LV) torsion is a force generated between a counterclockwise rotation of the ventricular apex, and a clockwise rotation of the base. It plays an important role in both LV systolic and diastolic function, and it is now widely accepted that LV torsion is sensitive to changes in both regional and global LV function. Echocardiography offers a new way of assessing LV torsion for its non-invasiveness, and instant availability. Twodimensional (2D) echocardiography using the papillary muscle as landmarks, Doppler Tissue Imaging (DTI), and Speckle Tracking Imaging (STI) are being competitively evaluated, to become a promising non-invasive tool for LV torsion assessment. 2D-echocardiography, however, does not meet the original idea of torsion, for it only measures one level, rather than whole LV length. Moreover, DTI shows angle dependency and low spatial resolution. STI, on the other hand, seems to be given the edge in this compe-