Journal Article

Investigation of hemodynamics in the development of dissecting aneurysm within patient-specific dissecting aneurismal aortas using computational fluid dynamics (CFD) simulations

Chiu, Peixuan, Tse, Kwong Ming, Lee, Heow Pueh, Ho, Pei

2011

Overview

Aortic dissecting aneurysm is one of the most catastrophic cardiovascular emergencies that carries high mortality. It was pointed out from clinical observations that the aneurysm development is likely to be related to the hemodynamics condition of the dissected aorta. In order to gain more insight on the formation and progression of dissecting aneurysm, hemodynamic parameters including flow pattern, velocity distribution, aortic wall pressure and shear stress, which are difficult to measure in vivo, are evaluated using numerical simulations. Pulsatile blood flow in patient-specific dissecting aneurismal aortas before and after the formation of lumenal aneurysm (pre-aneurysm and post-aneurysm) is investigated by computational fluid dynamics (CFD) simulations. Realistic time-dependent boundary conditions are prescribed at various arteries of the complete aorta models. This study suggests the helical development of false lumen around true lumen may be related to the helical nature of hemodynamic flow in aorta. Narrowing of the aorta is responsible for the massive recirculation in the poststenosis region in the lumenal aneurysm development. High pressure difference of 0.21kPa between true and false lumens in the pre-aneurismal aorta infers the possible lumenal aneurysm site in the descending aorta. It is also found that relatively high time-averaged wall shear stress (in the range of 4–8kPa) may be associated with tear initiation and propagation. CFD modeling assists in medical planning by providing blood flow patterns, wall pressure and wall shear stress. This helps to understand various phenomena in the development of dissecting aneurysm.

• Publisher: Elsevier Ltd,Elsevier,Elsevier Limited
• Subject: Aneurysm, Dissecting - pathology / Aneurysms / Aorta / Aorta - pathology / Aortic Aneurysm - pathology / Aortic dissecting aneurysm / Biological and medical sciences / Biomechanical Phenomena / Blood and lymphatic vessels / Blood flow / Cardiology. Vascular system / Computational fluid dynamics / Computational fluid dynamics (CFD) simulation / Computer Simulation / Computerized, statistical medical data processing and models in biomedicine / Diseases of the aorta / Fluid dynamics / Helical / Hemodynamics / Humans / Hydrodynamics / Imaging, Three-Dimensional / Lumenal aneursym / Lumens / Mathematical models / Medical imaging / Medical sciences / Models and simulation / Models, Cardiovascular / Models, Theoretical / Mortality / Physical Medicine and Rehabilitation / Pre- and post-aneurismal patient-specific models / Pressure / Shear stress / Stress, Mechanical / Tomography, X-Ray Computed - methods / Veins & arteries / Wall shear stresses