当前位置： SCI文献检索 > Biomechanics and Modeling in Mechanobiology期刊下所有文献 > Experimental measurement of dynamic fluid shear stress on the ventricular surface of the aortic valve leaflet.

Experimental measurement of dynamic fluid shear stress on the ventricular surface of the aortic valve leaflet.

Abstract：

:Aortic valve (AV) calcification is a highly prevalent disease with serious impact on mortality and morbidity. The exact causes and mechanisms of AV calcification are unclear, although previous studies suggest that mechanical forces play a role. It has been clinically demonstrated that calcification preferentially occurs on the aortic surface of the AV. This is hypothesized to be due to differences in the mechanical environments on the two sides of the valve. It is thus necessary to characterize fluid shear forces acting on both sides of the leaflet to test this hypothesis. The current study is one of two studies characterizing dynamic shear stress on both sides of the AV leaflets. In the current study, shear stresses on the ventricular surface of the AV leaflets were measured experimentally on two prosthetic AV models with transparent leaflets in an in vitro pulsatile flow loop using two-component Laser Doppler Velocimetry (LDV). Experimental measurements were utilized to validate a theoretical model of AV ventricular surface shear stress based on the Womersley profile in a straight tube, with corrections for the opening angle of the valve leaflets. This theoretical model was applied to in vivo data based on MRI-derived volumetric flow rates and valve dimension obtained from the literature. Experimental results showed that ventricular surface shear stress was dominated by the streamwise component. The systolic shear stress waveform resembled a half-sinusoid during systole and peaks at 64-71 dyn/cm(2), and reversed in direction at the end of systole for 15-25 ms, and reached a significant negative magnitude of 40-51 dyn/cm(2). Shear stresses from the theoretical model applied to in vivo data showed that shear stresses peaked at 77-92 dyn/cm(2) and reversed in direction for substantial period of time (108-110 ms) during late systole with peak negative shear stress of 35-38 dyn/cm(2).

journal_name

Biomech Model Mechanobiol

journal_title

Biomechanics and modeling in mechanobiology

authors

Yap CH,Saikrishnan N,Yoganathan AP

doi

10.1007/s10237-011-0306-2

subject

Has Abstract

pub_date

2012-01-01 00:00:00

pages

231-44

issue

1-2

eissn

1617-7959

issn

1617-7940

journal_volume

pub_type

杂志文章

在线工具

Experimental measurement of dynamic fluid shear stress on the ventricular surface of the aortic valve leaflet.