Concordance between the CURE index and mechanical resynchronization. A) Three-dimensional plot of relative mechanical activation time (time from QRS to peak circumferential strain) in a dog model of a dyssynchronous failing heart (with left bundle-branch block) and during CRT (biventricular pacing). The green dot shows the LV stimulation site. B) Synchrony indexed by CURE was calculated as a function of varying LV pacing site and plotted on three-dimensional maps, in which the colour red denotes optimal mechanical resynchronization. C) Combined maps derived for ventricular stroke work and synchrony (CURE) were determined in four failing hearts, and the territories producing optimal responses (70% maximal) for both were calculated and are displayed in green (far right). Adapted from Helm RH, et al.