Viscoelastic changes in the blood and vascular wall in a pulsating circular flow

• Authors: Merab Beraia , Fridon Todua , Irina Khomeriki
• Languages of publication: EN

Abstracts

EN

Altered flow conditions, such as separation and recirculationg zones, low and oscillatory shear stress, play an important role in the development of arterial disease. Endothelial denudation by the blood flow is the first step in atherosclerosis. The description of blood flow in vivo is complicated due to the viscoelasticity of vessel walls. However, conventional researches of the effect of the blood vessel viscoelasticity on the blood pressure wave propagation using non-linear one-dimensional models do not take into account the viscoelasticity, despite it being importance in the analysis of pulse wave propagation in arteries.The purpose of this paper is to study the impact of the arterial pulse wave on the viscoelastic blood flow and initial factors of atherosclerosis.In 12 healthy men (25-39 years of age) peak velocity, mean velocity, mean flow and net flow in the aorta have been investigated by MR angiography.Initial velocity was registered after 43msec of the ECG-R wave, and it differed from zero at all sites of the aorta, although net flow was equal to zero. Womersley's number from the ascending to the thoracic aorta decreased from 12.5 ± 1.5 to 7.3 ± 1.2; flow modified from inertio-elastic to viscous. Pulse pressure wave move on artery walls fifteen or more times more rapidly than the blood flow. In the aortic arch in protodiastole blood flow separated into the opposite directed streams resulting in wave superposition with the high net flow. At the isthmus area separated waves interferences and reflects to anterograde direction.Pulse oscillation increases strain rate to the contiguous vessel wall flow layers. At the sites with the flow wave negative interference vessel pulse oscillation attenuates and at the boundary reflection flow wave can shift the vessel wall.

Keywords

EN

arterial pulse; blood flow; wave propagation; blood viscoelasticity; endothelial denudation; magnetic resonance imaging; atherosclerosis

• Publisher: Versita
• Journal: Polish Journal of Medical Physics And Engineering
• Year: 2010
• Volume: 16
• Issue: 1
• Pages: 43-53

Dates

published

1 - 1 - 2010

online

5 - 5 - 2011

Contributors

author

Merab Beraia

• MRI Department, Institute of Clinical Medicine, Tbilisi, Georgia

author

Fridon Todua

• Institute of Clinical Medicine, Tbilisi, Georgia

author

Irina Khomeriki

• Department of Biomedical Enginering, Georgia Technical University, Tbilisi, Georgia

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Identifiers

DOI

10.2478/v10013-010-0005-9