Figure 1.

Changes in regional left ventricular myocardial work in responder (A) and non-responder (B) to cardiac resynchronization therapy. The pressure-strain loops are shown for the global left ventricular (LV) cardiac constructive work (CW) (in red) and for the indicated segments (in green). In the responder patient (A), after implantation of cardiac resynchronization therapy there is an increase in the LV CW and this is achieved by significant improvement in CW of the mid septal segment and normalization of the CW of the mid lateral segment. In the non-responder patient (B), the CW of the mid septal segment improves but the lateral wall remains impaired resulting in reduced LV CW. Reproduced with permission from Kostyukevich et al8bl, baseline; pi, post-implantation; WW, wasted work