1. Tasneem Z. Naqvi JIMG 2010;3:1168-1180
Effect of Sequential Ventricular Pacing on Mechanical Asynchrony Tissue synchronization images are shown in the apical 4-chamber view. Normal segments are coded in green, and delayed segments are coded in a progressive sequence of green, yellow, orange, and red. A is at a VV offset of 0 ms and optimal AV delay of 210 ms. Delay in systolic contraction is shown in the basal lateral wall, basal inferior interventricular septum, and RV free wall (white arrows in A). Homogenous contraction in LV and RV is seen after LV pre-excitation of 30 ms (B). Effect of RV pre-excitation on mechanical asynchrony is shown in another patient in C and D. Pacemaker was programmed at sensed AVD of 100 ms and LV pre-excitation of 20 ms. Marked delay in the RV free wall and interventricular septum (white arrows in C) was present at baseline settings. RV and septal delay decreased progressively as the VVD were changed to VV 0, right ventricular offset of 10, and then 15 ms (D). Abbreviations as in Figures 1, 4, and 6.
Tasneem Z. Naqvi JIMG 2010;3:
American College of Cardiology Foundation