Figure 1

Image planes used for CMR measurements. Panel A shows the flow velocity map was acquired at 3 image planes: -12 mm upstream from aortic valve plane (used as the 0 mm reference) and at +6 and +10 mm downstream of the aortic valve plane. The cross-sectional area of the LVOT is measured at the -12 mm position. Panel B shows the measurement of LVOT diameter at annulus location.