Instantaneous Pressure Distribution Along the Human Aorta

Pressures at various points of the human aorta were recorded and resolved into their sinusoidal components by Fourier analysis. A progressively decreasing phase angle with distance along the aorta was found. This was considered compatible with a traveling wave system. The pressure moduli generally increased with distance along the aorta. This was attributed to the progressively increasing stiffness of the aorta peripherally. Minor undulations in moduli could be explained on the basis of superimposed reflections. The apparent phase velocities were calculated for various points along the aorta. They tended to converge at higher frequencies to a value of 5 m/sec.