Speckle tracking radial strain analysis. Assessment of LV radial dyssynchrony and the latest mechanically activated segment by two-dimensional speckle tracking radial strain imaging. Time-strain curves are shown for the six mid-LV segments. This patient example illustrates LV dyssynchrony with a 266 ms delay between the septal and posterior segment. Site of the latest mechanical activation is the posterior segment (yellow arrow). Ant, anterior; Ant-Sept, antero-septal; Inf, inferior; Lat, lateral; Post, posterior; Sept, septum.