Large Eddy Simulation of Blood Flow Inside Vessels for Acoustic Diagnosis of Atherosclerosis

2018-10-20
Atherosclerosis is a cardiovascular disease, in which plaque builds up inside a blood vessel, narrowing it down and forming a stenosis that adversely affects flow. Because of the constriction, turbulent flow occurs at the post-stenotic region, which leads pressure fluctuations on the vessel wall. The murmur caused by this interaction propagates through the surrounding tissue and reaches the skin surface. These sounds emitted from the stenosed vessels are evaluated as a sign of stenosis. In this study, large eddy simulations are conducted to investigate the turbulence-induced wall pressure fluctuations and resulting acoustic emission. The two main parameters considered for this purpose are the stenosis severity and shape. The results show that stenosis severity under a certain level does not cause disturbance at the post-stenotic region. For constrictions above this critical level, increasing stenosis severity has an intensifying effect on the wall pressure fluctuations. Eccentric stenosis morphology causes more severe fluctuations than the axisymmetric one. Different stenosis shapes affect both the magnitude of fluctuations and the duration in which the fluctuations are intense during the pulsatile cycle. Obtained pressure fluctuations are converted into sound and investigated in terms of sound levels and patterns. Sounds emitted from the vessels with different stenosis severities and shapes have different sound characteristics, and they can provide important information about the constriction. Therefore, both the stenosis severity and the shape must be taken into account for development of an acoustic-based diagnostic system.
Citation Formats
C. Sert, Y. Yazıcıoğlu, and K. Özden, “Large Eddy Simulation of Blood Flow Inside Vessels for Acoustic Diagnosis of Atherosclerosis,” 2018, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/89085.