A comprehensive quantitative comparison of myocardial motion in mice, rabbits and humans using phase contrast MRI

Methods Phase contrast MRI [1] was used to measure regional three-directional LV myocardial motion with high temporal resolution in mice (N=18), rabbits (N=8), and humans (N=20). Radial, long-axis, and rotational myocardial velocities were acquired in left ventricular basal, mid-ventricular, and apical short-axis locations (see Table 1 for scan parameters). Positive radial velocities indicate contraction, positive long-axis velocities motion from base to apex, positive in-plane rotation is defined as clockwise viewed from apex to base. Global (averaged over the entire segmentation mask) and regional (by partitioning the LV into 16 segments according to the 17-segment model by the AHA) motion patterns were analyzed. Peak velocities were determined as well as velocity-ratios between lateral and septal wall, anterior and inferior wall, and basal and apical segments as dimensionless parameter for a comparison between species.