Question 17

Draw a labelled diagram of both the aortic root and radial artery pressure waveforms in a young adult using the same axis (60% of marks). Explain the factors that account for the differences between these two waveforms (40% of marks).

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College Answer

A well labelled diagram drawn clearly to demonstrate the salient features of the aortic and 
radial arterial pulses was expected. This would include the different systolic pressure, the 
absence of a dicrotic notch in the radial pulse (instead a diastolic hump), the narrowness and 
the delay of the radial pulse, garnered many marks.
Marks were lost for insufficient explanation such as the distance needed to travel for the 
pressure wave accounting for the delay, the sharper rise and decline of the radial pulse due to 
loss of the WIndkessel effect and the different compliance and the loss of the dicrotic notch 
due to summation and damping out of high frequency components of the pressure wave.