Modeling of Pulse Wave Propagation and Reflection Along Human Aorta

Pulse wave propagation along human aorta: a model study

“…In in vivo conditions, the active vasodilatation/constriction reactions of the side vessels can influence the blood distribution between the organs according to their demands. As it is observed in the in vitro and in vivo databases, the scatter in the wave reflection coefficients is always higher in a live patients (Kizilova et al, 2019;Hollander et al, 2001) because their arteries are always physiologically constricted, whereas in the post-mortem state all arteries are relaxed. Anyway, when the narrowing of some vessels is produced by stenosis, occlusion or other pathological reasons, the autoregulatory reactions might be insufficient to maintain the needed blood distribution along the aorta affected by the reverse flow at the end of systole (Salvi, 2017;Hughes et al, 2013).…”

“…In total, 150 pairs of P (t) and V (t) curves have been recorded (30 measurement sites per an individual) and used for validation of the individual 93-tube model of aorta (Kizilova and Mizerski, 2018). The detailed measurement data for the five individuals and the averaged values are reported in (Kizilova et al, 2019;Kizilova and Mizerski, 2018). Due to different body height of the individuals, their geometric models have been normalized by the total length along the aorta from the aortic valve to the aortic bifurcation.…”

“…4a,b respectively. The wave speeds have been computed on morphometric data (Kizilova et al, 2019;Kizilova and Mizerski, 2018) by (3.11), (3.12) or taken from the tables computed in (Wang and Parker, 2004;Epstein et al, 2015). The curves represent physically known dependence of the pulse wave velocity on the diameter of the blood vessel or (in experiments) latex tube (Nichols and O'Rourke, 2005;Hughes et al, 2013), as it is also clearly visible from (3.11).…”

“…The biomechanical model of aorta as a waveguide composed by 93 tubes has been presented in our previous studies (Kizilova and Mizerski, 2018;Kizilova et al, 2019). As it was shown there, the aorta is an optimal waveguide not only due to well-matched branching with zero wave reflections.…”

“…When the aortic length is scaled to 1, a clear regularity in the location of the sites of high positive, zero and negative wave reflections appears. An example of the distribution of such locations can be found in (Kizilova et al, 2019;Kizilova and Mizerski, 2018).…”