Nessa Johnson, John Abraham^*, Zach Helgeson, Michael Hennessey

Frontiers in Heat and Mass Transfer, Vol.2, No.2, pp. 1-7, 2011, DOI:10.5098/hmt.v2.2.3006

Abstract A numerical simulation has been performed on the hemodynamics associated with embolization procedures. The flow geometry includes a multibranch artery which is upstream of a targeted tumor. During the procedure, drug-eluting particles are released into the local arterial geometry and are carried downstream by the flowing blood. The intention is to cause embolization of a daughter artery which feeds the tumor. As particles are injected into the blood stream, and as the embolization progresses, it is possible for the particulates to substantially alter the blood flow in the main artery. This alteration may lead to a maldistribution of blood flow… More >

Wenyuan Chen¹, Tao Zhang², Yantao Yang^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.3, pp. 1-1, 2023, DOI:10.32604/icces.2023.09754

Abstract Based on the moving-least-squares immersed boundary method, we proposed a new technique to improve the calculation of the volume force representing the body boundary. For boundary with simple geometry, we theoretically analyze the error between the desired volume force at boundary and the actual force applied by the original method. The ratio between the two forces is very close to a constant and exhibits a very narrow distribution. A spatially uniform coefficient is then introduced to correct the force and can be fixed by the least-square method over all boundary markers. Such method is explicit and non-iterative, and is easy… More >

Shiyue Zhang¹, Xue Song^1,2, Jingying Wang^1,*, Wen Huang^3,*, Yue Zhou⁴, Mingrui Li¹

Molecular & Cellular Biomechanics, Vol.20, No.2, pp. 81-94, 2023, DOI:10.32604/mcb.2023.044445

Abstract Pulmonary embolism (PE), caused by deep venous thrombosis (DVT), is a disease with high morbidity and mortality. Implantation of inferior vena cava filters is an important method for the clinical prevention of PE. The hemodynamic characteristics of filters implanted in the inferior vena cava (IVC) have a significant impact on their performance. However, IVC diameters vary among patients. This may have a direct impact on the hemodynamic properties of the filter. At present, there is no research on this kind of problem to be investigated. In this paper, the hemodynamic properties of the VenaTech convertible filter were simulated in three… More > Graphic Abstract

Peishuo Wu¹, Chi Zhu^1,2,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.25, No.1, pp. 1-2, 2023, DOI: 10.32604/icces.2023.09869

Abstract Central blood pressure, i.e., the blood pressure near the heart, is an important physiological indicator of the cardiovascular function of a patient. However, direct measurement of this quantity is rarely carried out due to the invasive nature of the procedure. Instead, blood pressure at the arm (brachial artery) measured through an inflatable cuff is commonly used to represent or estimate the central blood pressure. On the other hand, the aortic pressure propagates downstream in the form of pulse waves, which have to pass through a complex and compliant vascular network to reach the brachial artery. Therefore, the efficacy of cuff-measured… More >

Jinlong Liu^1,2,#, Jing Shi^3,#, Weiru Luo¹, Zhirong Tong^1,2, Lefei Yang³, Peixuan Sun³, Tianyi Li³, Jun Du^3,*, Qian Wang^3,*

Congenital Heart Disease, Vol.18, No.1, pp. 41-55, 2023, DOI:10.32604/chd.2023.025005

Abstract Background: The assessment of renal function is important to the prognosis of patients needing Fontan palliation due to the reconstructed compromised circulation. To know the relationship between the kidney perfusion and hemodynamic characteristics during surgical design could reduce the risk of acute kidney injury (AKI) and the postoperative complications. However, the issue is still unsolved because the current clinical evaluation methods are unable to predict the hemodynamic changes in renal artery (RA). Methods: We reconstructed a three-dimensional (3D) vascular model of a patient requiring Fontan palliation. The technique of computational fluid dynamics (CFD) was utilized to explore the changes of… More > Graphic Abstract

Eloisa Sassá Carvalho^#, Maria Francilene S. Souza, Kelly Cristina O. Abud, Claudia R. P. Castro, Juliano G. Penha, Ana Maria Thomaz, Vanessa A. Guimarães, Antonio Augusto Lopes^*

Congenital Heart Disease, Vol.17, No.3, pp. 351-363, 2022, DOI:10.32604/chd.2022.019382

Abstract Background: Postoperative pulmonary hypertension limits the success of surgical treatment in some patients with unrestrictive congenital cardiac communications. Identifying patients at risk of developing postoperative pulmonary hypertension is important to individualize follow-up strategies. Methods: We analyzed a prospective cohort of 52 pediatric patients (age 3 to 35 months) looking for perioperative predictors of mildly elevated pulmonary arterial pressure 6 months after surgery, defined as a systolic pressure greater than 30 mmHg by transthoracic echocardiography. This corresponds to a mean pulmonary arterial pressure of >20 mmHg. Clinical, echocardiographic and hemodynamic parameters were investigated. Perioperative hemodynamics was assessed by directly measuring pulmonary and systemic… More >

Qingzhuo Chi¹, Huimin Chen¹, Shiqi Yang¹, Lizhong Mu^1,*, Changjin Ji², Ying He¹, Yong Luan³

CMES-Computer Modeling in Engineering & Sciences, Vol.131, No.1, pp. 31-47, 2022, DOI:10.32604/cmes.2022.018286

Abstract Cardiovascular computational fluid dynamics (CFD) based on patient-specific modeling is increasingly used to predict changes in hemodynamic parameters before or after surgery/interventional treatment for aortic dissection (AD). This study investigated the effects of flow boundary conditions (BCs) on patient-specific aortic hemodynamics. We compared the changes in hemodynamic parameters in a type A dissection model and normal aortic model under different BCs: inflow from the auxiliary and truncated structures at aortic valve, pressure control and Windkessel model outflow conditions, and steady and unsteady inflow conditions. The auxiliary entrance remarkably enhanced the physiological authenticity of numerical simulations of flow in the ascending… More >

Adi Azriff Basri^1,6,*, Mohammad Zuber², Ernnie Illyani Basri¹, Muhammad Shukri Zakaria⁵, Ahmad Fazli Abd Aziz³, Masaaki Tamagawa⁴, Kamarul Arifin Ahmad^1,6

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.3, pp. 531-553, 2021, DOI:10.32604/fdmp.2021.010925

Abstract Paravalvular Leakage (PVL) has been recognized as one of the most dangerous complications in relation to Transcathether Aortic Valve Implantation (TAVI) activities. However, data available in the literature about Fluid Structure Interaction (FSI) for this specific problem are relatively limited. In the present study, the fluid and structure responses of the hemodynamics along the patient aorta model and the aortic wall deformation are studied with the aid of numerical simulation taking into account PVL and 100% TAVI valve opening. In particular, the aorta without valve (AWoV) is assumed as the normal condition, whereas an aorta with TAVI 26 mm for… More >

Yunduo Charles Zhao^1,2,#, Parham Vatankhah^1,#, Tiffany Goh^1,2,3, Jiaqiu Wang⁴, Xuanyi Valeria Chen¹, Moein Navvab Kashani^5,6, Keke Zheng⁷, Zhiyong Li⁴, Lining Arnold Ju^1,2,3,*

Molecular & Cellular Biomechanics, Vol.18, No.1, pp. 1-10, 2021, DOI:10.32604/mcb.2021.012598

Abstract Platelet aggregation plays a central role in pathological thrombosis, preventing healthy physiological blood flow within the circulatory system. For decades, it was believed that platelet aggregation was primarily driven by soluble agonists such as thrombin, adenosine diphosphate and thromboxane A2. However, recent experimental findings have unveiled an intriguing but complementary biomechanical mechanism—the shear rate gradients generated from flow disturbance occurring at sites of blood vessel narrowing, otherwise known as stenosis, may rapidly trigger platelet recruitment and subsequent aggregation. In our Nature Materials 2019 paper [1], we employed microfluidic devices which incorporated micro-scale stenoses to elucidate the molecular insights underlying the… More >

Liesbeth van Dessel¹, Béatrice Santens², Els Troost², Pieter De Meester^2,3, Leen Roggen², Filip Rega^3,4, Bart Meyns^3,4, Bjorn Cools⁵, Marc Gewillig⁵, Philip Moons^6,7,8, Lukas Meier⁹, Werner Budts^2,3, Alexander Van De Bruaene^2,3,*

Congenital Heart Disease, Vol.15, No.2, pp. 69-78, 2020, DOI:10.32604/CHD.2020.011512

Abstract Background: Left-to-right shunt in sinus venosus septal defect (SVSD) may affect resistive (pulmonary vascular resistance–PVR) and elastic (pulmonary artery compliance-PAC) pulmonary artery properties. This study aimed at evaluating (1) impact of age, (2) pulmonary hemodynamics, and (3) outcome in a large cohort of SVSD patients. Methods: This study included 136 patients with SVSD (median age at diagnosis 14 (IQR 5–48) years, 47% male) of which 87 underwent catheterization. Pressures were measured and cardiac output was evaluated using the Fick principle at diagnosis. PVR, PAC and their product (RC time) were calculated. Results: Surgical repair was performed in 128 (94%) at… More >