Figure 1

Motion directions defined in the cardiac cycle: (a) radial movement in terms of contraction and expansion; (b) horizontal rotation is either clockwise or counterclockwise; and (c) vertical rotation is upwards or downwards. The two orientations for each direction are colored by the defined coding scheme (see Section 2.1.1). Movements are depicted using the short axis view in (a) and (b) and the horizontal long axis view in (c). The LV walls are depicted in (a) left: region 1 is the anterior wall; region 2 is the inferior wall; region 3 is the septal wall; and region 4 is the lateral wall. (The nomenclatures of cardiac planes and wall segments used in this work follow the recommendations of the American Heart Association, as described in Cerqueira et al. [18].)