Total arterial compliance is a main determinant of pulse pressure. For most part it resides in the aorta, where also major changes take place, which may differ locally. To follow local changes in aortic compliance, as in aging, noninvasive determination compliance distribution would be of great value.

Using MRI aortic diameters (area change deltaA) and flow were determined at 6 aortic locations. Simultaneously brachial blood pressure (BP) was measured with cuff. Aortic arch pressure AAP was calculated by setting diastolic and mean pressures equal [1]. Regional aortic pressures were estimated from AAP using (averaged) literature data on aortic pressure transfer [2,3]. Regional aortic compliance was then calculated in two ways, the pulse pressure method [4] and local area compliance (deltaA/deltaP) times segment length.

Studies were carried out in 7 healthy volunteers. The PPM of the AA includes head vessels while the area method does not, thus allowing compliance calculation of head vessels. Of the total arterial compliance, ascending to distal arch contributes (segments 1–3) 40%, descending aorta (segments 4&5) 25%, head/arms 15%, legs 20%.

Regional aortic compliance can be obtained non-invasively and thus allows following changes in local compliance (e.g., age effects). Compliance from local Pulse Wave Velocity should be compared but requires diameter information.