Fig. 4. Changes in the relative arterial elasticity and pressure differences from the aorta to each of the measurement points after cardiopulmonary bypass (CPB) in the positive–pressure gradient group (A ) and the negative–pressure gradient group (B ). Squares show the changes in arterial elasticity when aortic elasticity is 1. Plotted values were calculated from the mean values of the pulse wave velocity in figure 3, B or C , and Moens-Korteweg equation. Circles show the changes in pressure differences from the aorta to each measurement point (10-cm interval). ΔSAP = difference in systolic arterial blood pressure; ΔMAP = difference in mean arterial blood pressure.