Longling Fan^1,*, Jing Yao ^{2, *}, Chun Yang³, Di Xu², Dalin Tang^{1, 4, §}

CMES-Computer Modeling in Engineering & Sciences, Vol.114, No.2, pp. 221-237, 2018, DOI:10.3970/cmes.2018.114.221

Abstract Understanding cardiac blood flow behaviors is of importance for cardiovascular research and clinical assessment of ventricle functions. Patient-specific Echo-based left ventricle (LV) fluid-structure interaction (FSI) models were introduced to perform ventricle mechanical analysis, investigate flow behaviors, and evaluate the impact of myocardial infarction (MI) and hypertension on blood flow in the LV. Echo image data were acquired from 3 patients with consent obtained: one healthy volunteer (P1), one hypertension patient (P2), and one patient who had an inferior and posterior myocardial infarction (P3). The nonlinear Mooney-Rivlin model was used for ventricle tissue with material parameter… More >

Long Deng¹, Xueying Huang^2,3,*, Heng Zuo⁴, Yuan Zheng², Chun Yang⁵, Yunhu Song¹, Dalin Tang⁶

CMES-Computer Modeling in Engineering & Sciences, Vol.116, No.2, pp. 115-125, 2018, DOI:10.31614/cmes.2018.04076

Abstract The mechanisms of systolic anterior motion (SAM) of the mitral valve in hypertrophic obstructive cardiomyopathy (HOCM) remain unclear. To investigate the angle of attack between blood flow and mitral valve leaflets at pre-SAM time point, patient-specific CT-based computational models were constructed for 5 patients receiving septal myectomy surgery to obtain pre- and post-operative 2D vector flow mapping. The comparisons between pre- and post-operative angles of attack based on 2D vector flow mapping of 5 patients were performed. It was found that there was no statistically significant difference between pre- and post-operative angles of attack (61.1±t More >

Yanxia Wang¹, Yu Wang², Siqi Li³, ur Rehman Aziz³, Shutian Liu¹, Kairong Qin^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.116, No.2, pp. 127-147, 2018, DOI:10.31614/cmes.2018.03985

Abstract Assessment of the magnitude and pattern of wall shear stress (WSS) in vivo is the prerequisite for studying the quantitative relationship between exercise-induced WSS and arterial endothelial function. In the previous studies, the calculation of the WSS modulated by exercise training was primarily based upon the rigid tube model, which did not take non-linear effects of vessel elastic deformation into consideration. In this study, with an elastic tube model, we estimated the effect of a bout of 30-minute acute cycling exercise on the WSS and the flow rate in the common carotid artery according to… More >

Gaiping Zhao¹, Feiyi Xia¹, Eryun Chen², Xiaoli Yu³, Zhaozhi Yang^3,*

Molecular & Cellular Biomechanics, Vol.14, No.1, pp. 47-57, 2017, DOI:10.3970/mcb.2017.014.049

Abstract Metastatic tumor blood perfusion and interstitial fluid transport based on 3D microvasculature response to inhibitory effect of angiostatin are investigated in this paper. 3D blood flow、interstitial fluid transport and transvascular flow are described by the extended Poiseuille’s, Darcy’s and Starling’s law, respectively. Numerical solutions reveal that angiostatin can promote improved blood perfusion and decrease elevated interstitial fluid pressure within the metastatic tumor microenvironment. Moreover, angiostatin can increase interstitial convection within the tumor and result in more efficient drug delivery and penetration within the metastatic tumor, which suits well with the experimental observations. Together, our results More >

PoojaJhunjhunwala¹, P.M. Padole², S.B. Thombre³

Molecular & Cellular Biomechanics, Vol.13, No.1, pp. 1-21, 2016, DOI:10.3970/mcb.2016.013.001

Abstract This paper presents Computational fluid dynamic (CFD) analysis of blood flow in three different 3-D models of left coronary artery (LCA). A comparative study of flow parameters (pressure distribution, velocity distribution and wall shear stress) in each of the models is done for a non-Newtonian (Carreau) as well as the Newtonian nature of blood viscosity over a complete cardiac cycle. The difference between these two types of behavior of blood is studied for both transient and steady states of flow. Additionally, flow parameters are compared for steady and transient boundary conditions considering blood as non-Newtonian More >

M. Moatamedi^∗, M. Souli^†, E. Al-Bahkali^‡

Molecular & Cellular Biomechanics, Vol.11, No.4, pp. 221-234, 2014, DOI:10.3970/mcb.2014.011.221

Abstract This paper describes the capabilities of fluid structure interaction based multi-physics numerical modelling in solving problems related to vascular biomechanics. In this research work, the onset of a pressure pulse was simulated at the entrance of a three dimensional straight segment of the blood vessel like circular tube and the resulting dynamic response in the form of a propagating pulse wave through the wall was analysed and compared. Good agreement was found between the numerical results and the theoretical description of an idealized artery. Work has also been done on implementing the material constitutive models More >

Wei Huang^∗, Jun Shi^†, R. T. Yen^†,‡

Molecular & Cellular Biomechanics, Vol.9, No.4, pp. 269-284, 2012, DOI:10.3970/mcb.2012.009.269

Abstract The objective of our study was to develop a computing program for computing the transit time frequency distributions of red blood cell in human pulmonary circulation, based on our anatomic and elasticity data of blood vessels in human lung. A stochastic simulation model was introduced to simulate blood flow in human pulmonary circulation. In the stochastic simulation model, the connectivity data of pulmonary blood vessels in human lung was converted into a probability matrix. Based on this model, the transit time of red blood cell in human pulmonary circulation and the output blood pressure were More >

B. Liu¹, D. Tang²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.2, pp. 55-60, 2011, DOI:10.3970/icces.2011.017.055

Abstract The effects of the non-Newtonian blood viscosity on the wall shear stress (WSS) of the blood flows in stenotic right coronary arteries have been investigated by computer simulations. The numerical calculations were performed using the Newtonian Model and the non-Newtonian models with the fluid obeying the Power Law and the Carreau models for the simulations of unsteady blood flows. The differences on the spatial and temporal WSS distribution patterns due to the different blood properties were compared. The computational results demonstrate that the blood viscosity properties do not affect the spatial WSS distribution pattern qualitatively.… More >

Biyue Liu^∗, Dalin Tang^†

Molecular & Cellular Biomechanics, Vol.8, No.1, pp. 73-90, 2011, DOI:10.3970/mcb.2011.008.073

Abstract The objective of this work is to investigate the effect of non-Newtonian properties of blood on the wall shear stress (WSS) in atherosclerotic coronary arteries using both Newtonian and non-Newtonian models. Numerical simulations were performed to examine how the spatial and temporal WSS distributions are influenced by the stenosis size, blood viscosity, and flow rate. The computational results demonstrated that blood viscosity properties had considerable effect on the magnitude of the WSS, especially where disturbed flow was observed. The WSS distribution is highly non-uniform both temporally and spatially, especially in the stenotic region. The maximum More >

Bhaskar Chandra Konala^∗, Ashish Das^∗, Rupak K Banerjee^∗,†

Molecular & Cellular Biomechanics, Vol.8, No.1, pp. 1-20, 2011, DOI:10.3970/mcb.2011.008.001

Abstract Hemodynamic endpoints such as flow and pressure drop are often measured during angioplasty procedures to determine the functional severity of a coronary artery stenosis. There is a lack of knowledge regarding the influence of compliance of the arterial wall-stenosis on the pressure drop under hyperemic flows across coronary lesions. This study evaluates the influence in flow and pressure drop caused by variation in arterial-stenosis compliance for a wide range of stenosis severities. The flow and pressure drop were evaluated for three different severities of stenosis and tested for limiting scenarios of compliant models. The Mooney-Rivlin… More >