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Cardiovascular system
Published in A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha, Clark’s Procedures in Diagnostic Imaging: A System-Based Approach, 2020
A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha
Figures 9.35a,b show the major branches of the thoracic and abdominal aorta. The abdominal aorta bifurcates into the right and left common iliac arteries, usually at the level of L4. Each common iliac artery further divides into the internal iliac artery, which supplies the pelvis, and the external iliac artery, which continues down the leg to become the common femoral artery (CFA) once it crosses below the inguinal ligament. A few centimetres below the inguinal ligament the CFA divides into the deep (profunda femoris, PFA) and superficial femoral (SFA) arteries.
Hemodynamic analysis of hybrid treatment for thoracoabdominal aortic aneurysm based on Newtonian and non-Newtonian models in a patient-specific model
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2023
Jun Wen, Jiarong Wang, Liqing Peng, Ding Yuan, Tinghui Zheng
In most cases, the distal abdominal aorta (AA) or common iliac arteries are used as the inflow site for the aortic visceral reconstruction, namely retrograde visceral revascularization (RVR) (Moulakakis et al. 2011). However, it is still much debated that whether the retrograde flow generated by RVR surgery may lead to unfavorable hemodynamics, and further result in thrombus deposition, enhance intimal hyperplasia and even contribute to a high risk of AAA rupture (Davies 2009; Chiesa et al. 2014; Boyd et al. 2016; Apruzzi et al. 2019). Moreover, disturbed flow can induce low and oscillated WSS and flow recirculation, which may result in long particle residence time, atherosclerotic formation and intimal thickening (Ku et al. 1985; Davies 2009; Tanweer et al. 2014). The above studies suggest that the investigation of relationship between blood flow hemodynamics and RVR may be conducive to seek out the mechanism of instability of hybrid repair.
Flow analysis of aortic dissection: comparison of inflow boundary conditions for computational models based on 4D PCMRI and Doppler ultrasound
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2021
Zhenfeng Li, Shichao Liang, Huanming Xu, Minjia Zhu, Yuqian Mei, Jiang Xiong, Duanduan Chen
The current study focused on investigating the influence of the IBCs on the downstream flow system of AD. All the outlets of the models were thus unified. Velocity information of the three aortic arch branches was extracted from 4D PCMRI of the patient case, as shown in Figure 2b. Approximately 12.7% of the inlet flow volume was diverted to brachiocephalic trunk, while 3.2% and 3.1% of the inflow were diverted to the left common carotid artery and left subclavian artery respectively. Generally, they presented the parabolic velocity profile and the time-variant flow waveforms could be captured by the 4D PCMRI. Detailed information regarding the personalized flow division was displayed in S4, Supporting Document. Apart from the aortic arch branches, the outlets of the celiac artery, superior mesenteric artery, renal arteries and the common iliac arteries were assigned as the pressure outlets. So far, non-invasive pressure measurements of these sites were not available. A few computational studies applied the pressure data that were published previously(Tse et al. 2011; Naim et al. 2016). Here we applied the pulsatile pressure waveforms that were also used in our previous study (Vignon-Clementel et al. 2006). Its rationality was discussed in S5, Supporting Document.
Numerical simulations of flow pattern and particle trajectories in feline aorta for hypertrophic cardiomyopathy heart conditions
Published in Engineering Applications of Computational Fluid Mechanics, 2018
M. Borse, S. Bhushan, D. K. Walters, G. W. Burgreen
The feline aorta model (Figure 2) consists of an ascending aorta, which starts from the left ventricle, an arch section that leads to the thoracic aorta and later becomes the abdominal aorta, and terminates in a trifurcation. The major arteries considered for the feline aorta are: brachiocephalic trunk, left subclavian artery, celiac artery, CrMA, right and left renal arteries, CuMA, and right, left and common iliac arteries. The CAD model is generated using the dimensions of the feline aorta of Samii, Biller, and Koblik (1998), and any missing information is estimated by scaling the dimensions of the human aorta (Moore et al., 1992). Details of the aorta geometry and dimensions are summarized in Table 1. Initially, a coarse grid consisting of 1.5M tetrahedral cells with averaged y+ ∼ 2 is generated, then adaptively refined using a grid refinement ratio rG = √2 to obtain grids with 4.2M cells (medium) and 11M (fine) cells with averaged y+ = 1.2 and 0.9, respectively.