AJP - Heart and Circulatory Physiology, Vol 253, Issue 2 299-H306, Copyright © 1987 by American Physiological Society
Nonhuman primate model for regional wave travel and reflections along aortas
R. D. Latham, B. J. Rubal, N. Westerhof, P. Sipkema and R. A. Walsh
Arterial pulse transmission and wave reflections were studied in five
mature anesthetized baboons (Papio anubis) using multisensor
micromanometry. Simultaneous pressures were recorded from the left
ventricle and every 10 cm along the aorta and its terminal branches, and
flow velocity was measured in the aortic root. Aortic input impedance and
regional foot-to-foot and apparent phase velocities were calculated.
Aortography provided dimensional data for local reflection coefficients.
Regional foot-to-foot wave speeds were somewhat lower than corresponding
segments in humans. Proximal aortic pressure waveforms and characteristic
impedance (110 +/- 29 dyn X s X cm-5) were not characteristic of
middle-aged humans. Reflection coefficients at the terminal aortic
bifurcation (0.06) at the level of the renal artery branches (0.09) were
less than those found in humans. We conclude that the junction of the renal
artery branches and the aorta in the baboon is closely matched and
represents much less of a discrete reflection site than in humans. Although
the baboon may be used to study pulse transmission characteristics in the
baboon, this species is not a good model for the proximal systemic
reflective characteristics of normal middle-aged humans.
