Development of an In Vitro PIV Setup for Preliminary Investigation of the Effects of Aortic Compliance on Flow Patterns and Hemodynamics
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The aorta with its compliance plays a major role in hemodynamics as it saves a portion of ejected blood during systole which is then released in diastole. The aortic compliance decreases with increasing age, which is related to several cardiovascular imparities and diseases. Changes in flow patterns and pressure curves, due to varying aortic compliance, are difficult to investigate in vivo. As a result, the aim of the present work was to develop an in vitro setup enabling standardized investigations on the effect of compliance changes on flow patterns and pressure curves. Therefore an experimental setup with an anatomically correct silicone phantom of the aortic arch was developed, suitable for optical flow measurements under pulsatile inflow conditions. The setup was developed for precise adjustments of different compliances and optical flow measurements. Particle image velocimetry measurements were carried out downstream of the aortic valve in the center plane perpendicular to the valve with compliance adjusted between 0.62 × 10−3 to 1.82 × 10−3 mmHg−1. Preliminary results of the in vitro investigations showed that decreases in compliance results in significant increases in pressure changes with respect to time (dp/dt) and altered pressure curves in the aortic arch. In terms of flow, an increased aortic stiffness lead to higher mean velocities and decreased vortex development in the aortic sinuses. As in vivo validation and translation remains difficult, the results have to be considered as preliminary in vitro insights into the mechanisms of (age-related) compliance changes.
KeywordsAortic compliance Aortic flow Hemodynamics Particle image velocimetry
Laser Doppler velocimetry
Neodymium-doped yttrium lithium fluoride
Particle image velocimetry
Particle tracking velocimetry
Pressure change with respect to time (mmHg s−1)
Dynamic viscosity (Pa s)
Density (kg m−3)
Velocity (cm s−1)
Conflict of interest
Martin Büsen, Christian Arenz, Michael Neidlin, Sam Liao, Thomas Schmitz-Rode, Ulrich Steinseifer and Simon Sonntag declare that they have no conflict of interest.
This article does not contain any studies with human participants or animals performed by any of the authors.
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