Study of Coronary Atherosclerosis Using Blood Residence Time

Hashemi, Javad; Patel, Bhavesh; Chatzizisis, Yiannis S.; Kassab, Ghassan S.

doi:10.3389/fphys.2021.625420

Cited by 16 publications

(13 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Some studies had proved that leukocytes and other substances in this area may have a stronger migration and adhesion effect, which may increase the risk of atherosclerosis formation. 39,[62][63][64] Moreover, low TAWSS, high OSI, and high RRT are risk factors for rupture-prone phenotype, which may be related to lipid accumulation and inflammatory cell infiltration to the intima, and correlated with neointimal thickening. In the case of three factors acting together, this leads to an increased risk of stenosis and atherosclerosis formation.…”

Section: Discussionmentioning

confidence: 99%

Numerical simulation in the abdominal aorta and the visceral arteries with or without stenosis based on 2D PCMRI

Chen

Liu

et al. 2022

Numer Methods Biomed Eng

View full text Add to dashboard Cite

It is important to obtain accurate boundary conditions (BCs) in hemodynamic simulations. This article aimed to improve the accuracy of BCs in computational fluid dynamics (CFD) simulation and analyze the differences in hemodynamics between healthy volunteers and patients with visceral arterial stenosis (VAS). The geometric models of seven cases were reconstructed using the magnetic resonance angiogram (MRA) or computed tomography angiogram (CTA) imaging data. The physiological flow waveforms obtained from 2D Phase Contrast Magnetic Resonance Imaging (PCMRI) were imposed on the aortic inlet and the visceral arteries' outlets. The individualized RCR values of the three-element Windkessel model were imposed on the aortic outlet.CFD simulations were run in the open-source software: svSolver. Two specific time points were selected to compare the hemodynamics of healthy volunteers and patients with VAS. The results suggested that blood in the stenotic visceral arteries flowed at high speed throughout the cardiac cycle. The low pressure is distributed at stenotic lesions. The wall shear stress (WSS) reached 4 Pa near stenotic locations. The low time average wall shear stress (TAWSS), high oscillatory shear index (OSI), and high relative residence time (RRT) concentrated in the abdominal aorta. Besides, the ratios of the areas with low TAWSS, high OSI, and high RRT to the computational domain were higher in patients with VAS than which in the healthy volunteers. The individualized BCs were used for hemodynamic simulations and results suggest that patients with stenosis have a higher risk of blood retention and atherosclerosis formation in the abdominal aorta.

show abstract

Section: Discussionmentioning

confidence: 99%

Numerical simulation in the abdominal aorta and the visceral arteries with or without stenosis based on 2D PCMRI

Chen

Liu

et al. 2022

Numer Methods Biomed Eng

View full text Add to dashboard Cite

show abstract

“…For further work, the range of prediction tools can be extended by considering further multidirectional WSS parameters, where the choice of the tangential field is of particular importance. According to [14], time-averaged WSS (TAWSS; [2,20]) and relative residence time (RRT; [12,13,35]) are strong predictive clinical markers for disease development, even in early stages of atherosclerosis. Moreover, transversal WSS ( [23,30,31]) and cross flow index (CFI, [23]) shown a predictive value when complex fluid flow appears in later phases of atherosclerosis.…”

Section: Discussionmentioning

confidence: 99%

Proper tangential vector field for the wall shear stress evaluation in numerical blood flow simulations in human carotis tree

Richter¹,

Probst²,

Hundertmark³

et al. 2022

Preprint

View full text Add to dashboard Cite

In numerical simulations of the cardiovascular system the realistic depiction of the blood vessel is essential. The vessel morphology plays a critical role in the underlying hemodynamical computation, for which 3D geometries are obtained via imaging techniques from patients' CTA or MRI scans. To evaluate the patients' current risks suffering vessel wall damage or an ischemic stroke, areas of interest are closely observed. A main indicator for these defects is the stress the blood is exerting on the surrounding vessel tissue. The wall shear stress (WSS) and its cyclic evaluation as the oscillatory shear index (OSI) can be used as an indicator for future medical procedures. As a result of low resolution imaging and craggy stenotic surface areas, the geometry model's mesh is often non smooth on the surface areas. The automatically generated tangential vector fields of such a surface topology are sometimes strongly non unidirectional. Making an interpretation of the orientation-based WSS difficult and partially unreliable. To smooth out the erratic surface tangential field, we apply a projection of the vessel's center-line tangents to the surface. We validate our approach by comparing the orientation focused evaluation of the WSS to the generic method with automatically generated tangential vectors. The results of this work focus on the carotid bifurcation and a distal stenosis area in the internal carotid artery.

show abstract

“…Patient specific model identification will increase the applicability of the model and reduce its prediction uncertainty. The inclusion of vessel specific biomechanical properties and inclusion of a reactive vascular tone module [36][37][38] is expected to allow simulation of clinical parameters such as pulse wave velocities and residence times [39][40][41][42][43][44]. The inclusion of autoregulatory processes will further assist to make the model's FFR estimates quantitatively reliable [45].…”

Section: Modelmentioning

confidence: 99%

Structure (Epicardial Stenosis) and Function (Microvascular Dysfunction) that Influences Coronary Fractional Flow Reserve Estimation

Joseph¹,

Sun²,

Lee³

et al. 2022

Preprint

View full text Add to dashboard Cite

Background. The treatment of coronary stenosis relies on invasive high risk surgical assessment to generate the fractional flow reserve diagnostics index, a ratio of distal to proximal pressures in respect of coronary atherosclerotic plaque causing stenosis. Non-invasive methods are therefore a need of the times. This study proposes an extensible mathematical description of the coronary vasculature that permits rapid estimation of the coronary fractional flow reserve. Methods. By adapting an existing closed loop model of human coronary blood flow, the effects of large vessel stenosis and microvascular disease on fractional flow reserve were quantified. Several simula-tions generated flow and pressure information which was used to compute fractional flow re-serve under a spectrum of conditions including focal stenosis, diffuse stenosis, and microvascular disease. Sensitivity analysis stratified the influence of model parameters on the index. The model was simulated as coupled non-linear ordinary differential equations and numerically solved us-ing an implicit higher order method. Results. Large vessel stenosis affected fractional flow re-serve. The model predicts that the presence, rather than severity, of microvascular disease affect coronary flow deleteriously. Sensitivity analysis revealed that heart rate may not affect the index. Conclusions. The model provides a computationally inexpensive instrument for future in silico coronary blood flow investigations as well as clinical-imaging decision making. A combination of focal and diffuse stenosis appears to be essential in reducing the index. In addition to pressure measurements in the large epicardial vessels, diagnosis of microvascular disease is essential. The independence of the index with respect to heart rate suggests that computationally inexpensive steady state simulations may provide sufficient information to reliably compute the index.

show abstract

Study of Coronary Atherosclerosis Using Blood Residence Time

Cited by 16 publications

References 33 publications

Numerical simulation in the abdominal aorta and the visceral arteries with or without stenosis based on 2D PCMRI

Numerical simulation in the abdominal aorta and the visceral arteries with or without stenosis based on 2D PCMRI

Proper tangential vector field for the wall shear stress evaluation in numerical blood flow simulations in human carotis tree

Structure (Epicardial Stenosis) and Function (Microvascular Dysfunction) that Influences Coronary Fractional Flow Reserve Estimation

Contact Info

Product

Resources

About