Fig. 2.

(a) The common center axis of the PA along with individual center axes points (black) from multiple time points (scaled), with the Frenet frame and global Cartesian coordinate systems. Note the high degree of consistency between the centerline paths from the animals studied. Also shown in (b) are the AA and PA center axes from two perspectives to demonstrate larger tortuosity of PA compared to AA. (c) A schematic surface parameterization and deformation showing the base vectors in the reference to the end-diastolic loaded state of the youngest animal (15 kg) and those of current or ‘deformed’ geometry and the fitted centerline (CL).