Left ventricle
For two-dimensional global longitudinal peak strain, three consecutive
cardiac cycles in the apical two, three and four-chamber views were
acquired for analysis with frame rates between 50 to 80 frames/second
using velocity vector imaging. The automatized software tracked the
contour of the endocardium and automatically divided the left ventricle
into six segments. Deformation was assessed frame by frame. Left
ventricular global longitudinal strain represents the apical to base
deformation, and it is expressed with negative values because the LV
shortens during systole. More negative values are associated with a
better longitudinal performance. Decreased LV-GS was defined as values
≥-20% as previously described (Figure 2A) (13).