Figure 1

Circumferential velocity graphs for LV segments according to the AHA segment model (segments 1-6 are basal, 7-12 midventricular and 13-16 apical). The graphs represent the average values of all volunteers. Positive values show clockwise rotation as viewed from the apex, whilst negative values represent counter-clockwise rotation. Phases of the cardiac cycle: 1 - isovolumetric contraction, 2 - rapid ejection, 3 - reduced ejection, 4 - isovolumetric relaxation, 5 - rapid filling, 6 - diastasis, 7 - atrial systole, ED - end diastole, ES - end systole.