Dynamic intra-vascular pressure harmonic analysis
Stinnett, H.; Wheeldon, J.; Hennes, M.
Biomedical Sciences Instrumentation 29: 443-450
1993
ISSN/ISBN: 0067-8856 PMID: 8329625 Document Number: 412901
The postulate that dynamic intra vascular pressure is a function of positional wall properties has been difficult to verify due to non-linear viscoelastic influences in arteries. It was tested, in rabbit carotid artery in vitro segments using dynamic and static input. A Multifunction Pressure Generator (MPG, Millar Inc.) provide dynamic input of defined swept frequency (2-200 Hz) pressure superimposed on multiple levels of mean intraluminal pressure (IP). Bode plots were analyzed for natural frequency (omega n), gain (dB) and damping (zeta) of the IP/MPG transfer function. An increase in omega n (all zeta > 0.25) was found with increase in mean IP. An increase in segment Elastic modulus (Em) was found with increase in static force input. Relation between Em and omega n results was demonstrative of non-linear elasticity. Results supported the postulate and verified estimating vessel properties by harmonic analysis.