Figure 12

Tissue velocity (A, B and C) and strain rate (D, E and F) maps in the apical 2 chamber view at baseline pre cardiac resynchronization treatment (A and D), post cardiac resynchronization treatment with LV pre-excitation of 20 ms (B and E) and post optimization with RV pre-excitation of 20 ms (C and F). Note delayed longitudinal contraction (shown by white arrows) in the velocity (A) and strain rate maps (D) at baseline indicated by white arrows that is abolished in all segments in the velocity map in B and in mid inferior segment in the strain rate map in E post cardiac resynchronization treatment. In addition note the marked improvement in synchrony in systole between basal and mid segments post cardiac resynchronization treatment in B and E compared to A and D. RV pre-excitation causes further increase in velocities with establishment of a normal velocity gradient between basal and mid segments and improved synchrony in C, as well as improvement in strain rate velocities, synchrony and a reduction of delayed longitudinal contraction velocities in F. Note different velocity calibration settings between D-F. Yellow line represent basal inferior LV segment, blue represents basal anterior LV segment, red represents mid inferior LV segment and green mid anterior LV segment.