Fig. 3

a Illustration of the transit time pulse wave velocity (PWV) measurement. Through-plane flow was determined at various positions along the aortic arch (for illustration only 8 planes are shown; in the experiment approx. 50 slices were used). b For each location (here shown for one plane in the ascending and descending aorta), the time point of the systolic upstroke was identified as the intersection of a line fitted to the pre-systolic data points and a line fitted to the upstroke of the early systolic pulse. c The distances Δx of each plane (relative to the proximal ascending aorta) were plotted against the time points of the systolic upstroke Δt (relative to the time point of the first plane). PWV was calculated from the slope of a line fitted to this plot