Aortic flow just distal to the aortic valve (arrow), picked up by Doppler interrogation. The velocity of 1 m/sec in this case is normal. The upper panel shows the apical five chamber view colour Doppler image used to guide the positioning of the Doppler cursor and sample volume (Diamond shaped). The colour bar on the top right shows the colour Doppler scale with a maximum velocity of 60 centimeter per second in this case. This scale applies to the upper panel. The aortic flow is depicted as blue in the upper panel because it is away from the transducer in the apical five chamber view. There is some colour variance due to aliasing as the velocity is above the Nyquist limit of the colour Doppler settings, which in this case is 60 centimeters per second and the aortic velocity is about 100 centimeters per second in this case. The scale below that is the Doppler velocity scale in meters per second and applies to the lower panel. Horizontal axis of the Doppler tracing is time.