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Numerical Simulation of an Aortic Flow Based on a HLLC Type Incompressible Flow Solver 被引量:3
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作者 Yang-Yao Niu Chih-Hung Chang +2 位作者 Wen-Yih I.Tseng Hsu-Hsia Peng Hsi-Yu Yu 《Communications in Computational Physics》 SCIE 2009年第1期142-162,共21页
In this study,a three-dimensional artificial compressibility solver based on the average-state Harten-Lax-van Leer-Contact(HLLC)[13]type Riemann solution is first proposed and developed to solve the time-dependent inc... In this study,a three-dimensional artificial compressibility solver based on the average-state Harten-Lax-van Leer-Contact(HLLC)[13]type Riemann solution is first proposed and developed to solve the time-dependent incompressible flow equations.To implement unsteady flow calculations,a dual time stepping strategy including the LU decomposition method is used in the pseudo-time iteration and the second-order accurate backward difference is adopted to discretize the unsteady flow term.Also a third-order accurate HLLC numerical flux is derived for approximating the inviscid terms.To verify numerical accuracy,flows over a lid-driven cavity and an oscillating flat plate are chosen as the benchmark tests.In addition,the current solver is extended to solve blood flows in a realistic human aorta measured from MRI(Magnetic Resonance Imaging).The simulation geometry was derived from a three-dimensional reconstruction of a series of two-dimensional slices obtained in vivo.Numerical results demonstrate wall stresses were highly dynamic,but were generally high along the outer wall in the vicinity of the branches and low along the inner wall,particularly in the descending aorta.The maximum wall stress distribution is presented on the aortic arch in the systole.In addition,extensive counter-clockwise secondary flows and three-dimensional helical vortex influenced considerably by the presence of vessel contraction,torsion and the branches were shown in the descending aorta in the late systole and early diastolic cycles. 展开更多
关键词 HLLC Riemann solver incompressible flow aortic flow fluid-structure interaction
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Three-dimensional lattice Boltzmann method for simulating blood flow in aortic arch 被引量:2
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作者 康秀英 吉驭嫔 +1 位作者 刘大禾 金永娟 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第3期1041-1049,共9页
The three-dimensional (3D) lattice Boltzmann models, 3DQ15, 3DQ19 and 3DQ27, under different wall boundary conditions and lattice resolutions have been investigated by simulating Poiseuille flow in a circular cylind... The three-dimensional (3D) lattice Boltzmann models, 3DQ15, 3DQ19 and 3DQ27, under different wall boundary conditions and lattice resolutions have been investigated by simulating Poiseuille flow in a circular cylinder for a wide range of Reynolds numbers. The 3DQ19 model with improved Fillippova and Hanel (FH) curved boundary condition represents a good compromise between computational efficiency and reliability. Blood flow in an aortic arch is then simulated as a typical haemodynamic application. Axial and secondary fluid velocity and effective wall shear stress profiles in a 180° bend are obtained, and the results also demonstrate that the lattice Boltzmann method is suitable for simulating the flow in 3D large-curved vessels. 展开更多
关键词 lattice Boltzmann method aortic arch secondary flow wall shear stress
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Real-time Three-Dimensional Color Doppler Flow Imaging: An Improved Technique for Quantitative Analysis of Aortic Regurgitation 被引量:3
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作者 吕清 刘夏天 +3 位作者 谢明星 王新房 王静 庄磊 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2006年第1期148-152,共5页
The recently introduced real-time three-dimensional color Doppler flow imaging (RT-3D CDFI) technique provides a quick and accurate calculation of regurgitant jet volume (RJV) and fraction. In order to evaluate RT... The recently introduced real-time three-dimensional color Doppler flow imaging (RT-3D CDFI) technique provides a quick and accurate calculation of regurgitant jet volume (RJV) and fraction. In order to evaluate RT-3D CDFI in the noninvasive assessment of aortic RJV and regurgitant jet fraction (RJF) in patients with isolated aortic regurgitation, real-time three-dimensional echocardiographic studies were performed on 23 patients with isolated aortic regurgitation to obtain LV end-diastolic volumes (LVEDV), end-systolic volumes (LVESV) and RJV, and then RJF could be calculated. The regurgitant volume (RV) and regurgitant fraction (RF) calculated by two-dimensional pulsed Doppler (2D-PD) method served as reference values. The results showed that aortic RJV measured by the RT-3D CDFI method showed a good correlation with the 2D-PD measurements (r= 0.93, Y=0.89X+ 3.9, SEE= 8.6 mL, P〈0.001 ); the mean (SD) difference between the two methods was - 1.5 (9.8) mL. % RJF estimated by the RT-3D CDFI method was also correlated well with the values obtained by the 2D-PD method (r=0.88, Y=0.71X+ 14.8, SEE= 6.4 %, P〈0. 001); the mean (SD) difference between the two methods was -1.2 (7.9) %. It was suggested that the newly developed RT-3D CDFI technique was feasible in the majority of patients. In patients with eccentric aortic regurgitation, this new modality provides additional information to that obtained from the two-dimensional examination, which overcomes the inherent limitations of two-dimensional echocardiography by depicting the full extent of the jet trajectory. In addition, the RT-3D CDFI method is quick and accurate in calculating RJV and RJF. 展开更多
关键词 real-time three-dimensional echocardiography color Doppler flow imaging aortic regurgitation
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Trans-Thoracic Echocardiographic Aortic Blood Flow Peak Velocity Variation, Distance Minute, Aortic Velocity Time Integral and Postoperative Outcome in Pediatric Surgical Patients—An Observational Pilot Study Protocol 被引量:1
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作者 Claudine Kumba 《Open Journal of Internal Medicine》 2020年第1期90-95,共6页
Background: A Randomized Controlled Trial (RCT) has been elaborated where goal directed fluid and hemodynamic therapy (GDFHT) will be realized with trans-thoracic echocardiographic aortic blood flow peak velocity vari... Background: A Randomized Controlled Trial (RCT) has been elaborated where goal directed fluid and hemodynamic therapy (GDFHT) will be realized with trans-thoracic echocardiographic aortic blood flow peak velocity variation (ΔVpeak) and distance minute (DM) to guide fluid therapy and hemodynamics in high risk pediatric surgical patients. This RCT will clarify the impact of GDFHT with ΔVpeak and DM on postoperative outcome in terms of morbidity, length of stay in the intensive care unit (LOSICU), length of mechanical ventilation (LMV) and length of hospital stay (LOS) in children. To determine values of ΔVpeak, DM and VTI predictive of these postoperative outcomes, an observational pilot study will be realized. This pilot study is described here. The primary objective of this study is to determine values of ΔVpeak, DM and ITV predictive of postoperative outcome in children in terms of morbidity. The secondary objectives are to determine values of ΔVpeak, DM and ITV predictive of LOSICU, LMV, LOS, intraoperative, postoperative fluid administration and vasoactive-inotropic therapy. Methods: 500 - 1000 children aged less than 18 years will be included prospectively. Statistic analysis will be realized with XLSTAT 2019.4.2 software or plus. Results and Conclusions: This trial protocol will determine values of ΔVpeak, DM and ITV with echocardiography predictive of postoperative outcome in children. 展开更多
关键词 Children aortic Blood flow Peak VELOCITY Variation aortic VELOCITY Time INTEGRAL Distance MINUTE Postoperative Outcome Pilot Study Protocol Trans-Thoracic Echocardiography
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4D Flow MRI在主动脉瓣疾病中的研究进展
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作者 刘峰 曹亮 +3 位作者 胡瑞 李瑞 陈梓娴 郭顺林 《中国医学影像学杂志》 CSCD 北大核心 2023年第9期990-994,共5页
主动脉瓣疾病是一种较为常见的心脏瓣膜病,与主动脉瓣疾病相关的血流动力学环境改变可以引起升主动脉血流模式改变,这与主动脉壁重构和主动脉病变的发展有关。4D Flow MRI提供了获取先进血流动力学指标的机会,使主动脉血流动力学的全面... 主动脉瓣疾病是一种较为常见的心脏瓣膜病,与主动脉瓣疾病相关的血流动力学环境改变可以引起升主动脉血流模式改变,这与主动脉壁重构和主动脉病变的发展有关。4D Flow MRI提供了获取先进血流动力学指标的机会,使主动脉血流动力学的全面可视化和量化成为可能。本综述介绍在主动脉瓣疾病的背景下,应用4D Flow MRI进行血流可视化和量化血流动力学指标的研究进展。 展开更多
关键词 主动脉瓣膜病 磁共振成像 血流动力学 四维血流磁共振成像 综述
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Maintenance of High Blood Pressure and Early Establishment of Pulsatile Blood Flow to the Spinal Cord during Thoracoabdominal Aortic Repair
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作者 Koji Furukawa Eisaku Nakamura +2 位作者 Masanori Nishimura Hirohito Ishii Kunihide Nakamura 《World Journal of Cardiovascular Surgery》 2018年第10期175-188,共14页
Objectives: Despite continuous advancements in the surgical treatments for thoracoabdominal aortic aneurysms (TAAA), paraplegia remains a devastating treatment-related complication. We aimed to summarize our experienc... Objectives: Despite continuous advancements in the surgical treatments for thoracoabdominal aortic aneurysms (TAAA), paraplegia remains a devastating treatment-related complication. We aimed to summarize our experience with a novel surgical strategy involving maintenance of high blood pressure and early establishment of pulsatile blood flow to the spinal cord. Materials and Methods: Between August 2011 and October 2017, 29 patients (age, 67 ± 12 years) underwent open surgery for TAAA. According to the Crawford classification, two aneurysms were type I, eight were type II, 12 were type III, and seven were type IV. We used partial cardiopulmonary bypass under mild hypothermia in all patients except one. By maintaining distal aortic perfusion pressure at 60 - 80 mmHg and creating the distal aortic anastomosis before visceral branch reconstruction, we established early perfusion of the hypogastric arteries with native pulsatile flow. Intraoperative spinal monitoring and cerebrospinal fluid drainage were performed in 26 (90%) and 23 (79%) patients, respectively. Nineteen patients (66%) underwent reconstruction of the intercostal arteries. During perioperative management, the mean arterial pressure was kept >80 mmHg. Results: No in-hospital deaths or acute neurological complications occurred. One patient (3.4%) experienced delayed temporal paraplegia. During follow-up, aorta-related death occurred in only one patient, who developed prosthetic vascular graft infection but did not undergo repeat graft replacement. The 3-year freedom from aortic-related death was 95%. Conclusion: Our surgical strategy involving maintenance of high blood pressure and early establishment of pulsatile flow to the spinal cord was effective in preventing spinal cord injury following open surgery for TAAA. 展开更多
关键词 THORACOABDOMINAL aortic ANEURYSM Open Surgery High-Blood-Pressure Maintenance PULSATILE flow
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Paradoxical Low Flow Low Gradient Severe Aortic Stenosis—An Under-Recognized Entity
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作者 Phillip Crane Mandeep Singh Kalsi +1 位作者 Matias Yudi Naveen Sharma 《Case Reports in Clinical Medicine》 2022年第2期31-36,共6页
Some patients with severe aortic stenosis (AS), due to restrictive cardiac physiology, paradoxically have relatively low flow and low gradients across stenotic aortic valves despite preserved left ventricular (LV) sys... Some patients with severe aortic stenosis (AS), due to restrictive cardiac physiology, paradoxically have relatively low flow and low gradients across stenotic aortic valves despite preserved left ventricular (LV) systolic function. It results in symptoms and reduced quality of life and carries a high mortality. Whilst this form of severe AS, termed paradoxical low flow low gradient (pLFLG), is well reported, patients with this diagnosis experience inappropriate barriers to aortic valve replacement (AVR), the only efficacious treatment. We present the case of an 88-year-old female with 12 months of exertional dyspnoea on a background of hypothyroidism and hypercholesterolemia. Transthoracic echocardiogram (TTE) revealed LV hypertrophy, with a small LV cavity size and reduced stroke volume, yet normal systolic function. A heavily calcified aortic valve was identified with severe aortic stenosis, based on valve area, yet with incongruous mean transvalvular gradient of 25 mmHg (severe ≥ 50 mmHg). Following exclusion of other differential diagnoses, her symptoms were attributed to paradoxical LFLG severe AS. She was however declined definitive transcatheter aortic valve implantation (TAVI) due to her paradoxically low mean aortic gradient. Following further deterioration in her symptoms and supportive quantification of poor exercise performance, she was ultimately re-referred, accepted, and underwent TAVI. Following her AVR, the patient experiences significant improvement in both symptoms and quality of life after only one month. Paradoxical LFLG severe AS remains a well-documented yet under recognized disease. It carries high morbidity and mortality if untreated, yet is significantly less likely to be referred and accepted for intervention. With its prevalence expected to rise with an ageing population, this case serves as a timely reminder for clinicians to address the under recognition of important pathology. 展开更多
关键词 Paroxysmal Low flow Low Gradient Doppler Echocardiography aortic Valve Stenosis aortic Valve Implantation Valvular Heart Disease
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iFlow软件在B型主动脉夹层血流动力学评估中的价值 被引量:2
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作者 刘光锐 郭曦 +7 位作者 吴文辉 黄小勇 李铁铮 韩晓峰 薛玉国 濮欣 蒲俊舟 黄连军 《中国医药》 2017年第2期207-210,共4页
目的探讨iFlow软件在B型主动脉夹层血流动力学评估中的价值。方法选取2016年1—3月首都医科大学附属北京安贞医院39例因B型主动脉夹层行胸主动脉腔内修复术患者,在术中行数字减影血管造影检查时,应用iFlow软件进行影像后处理而得到彩... 目的探讨iFlow软件在B型主动脉夹层血流动力学评估中的价值。方法选取2016年1—3月首都医科大学附属北京安贞医院39例因B型主动脉夹层行胸主动脉腔内修复术患者,在术中行数字减影血管造影检查时,应用iFlow软件进行影像后处理而得到彩色编码血流图的影像资料,对比分析真、假腔造影剂的达峰时间,分析达峰时间与测量点距离的相关性。结果39例患者中,有2例患者因后前位上无法区分真、假腔而予以排除;余37例患者均成功行iFlow重建,其中男30例、女7例。真腔4个测量点达峰时间差异无统计学意义(P〉0.05);假腔4个测量点达峰时间分别为(3.4±1.3)、(3.8±1.4)、(4.0±1.4)、(4.5±1.3)s,数据间差异有统计学意义(F=3.920,P〈0.05)。真腔、假腔达峰时间随着降主动脉测量点距离的增加而均呈增加趋势(r2=0.034、0.075,均P〈0.05)。真腔总体达峰时间为(2.9±0.8)s,假腔为(3.9±1.4)s,假腔血流速度慢于真腔,差异有统计学意义(P〈0.01)。结论iFlow对于计算B型主动脉夹层腔内血流速度有较大的临床价值,可用于评估主动脉夹层的血流动力学,是主动脉夹层影像诊断评估的一种新方法。 展开更多
关键词 主动脉夹层 数字减影血管造影术 彩色编码血流图
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Newer echocardiographic techniques for aortic-valve imaging: Clinical aids today, clinical practice tomorrow 被引量:1
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作者 Nidhish Tiwari Kavisha Patel 《World Journal of Cardiology》 CAS 2018年第8期62-73,共12页
Increasing life expectancy is expected to lead to a corresponding increase in the prevalence of aortic valve disease(AVD). Further, the number of indications for transcatheter aortic valve replacement(TAVR) as a treat... Increasing life expectancy is expected to lead to a corresponding increase in the prevalence of aortic valve disease(AVD). Further, the number of indications for transcatheter aortic valve replacement(TAVR) as a treatment option for AVD is expanding, with a growing role for echocardiography in its management. In this review we summarize the current literature on some newer echocardiographic modalities and the parameters they generate, with a particular focus on their prognostic and clinical value beyond conventional methods in the management of aortic stenosis, TAVR, and aortic regurgitation. Speckle tracking and 3 D echocardiography are now increasingly being used in the management of AVD. For instance, global longitudinal strain, the beststudied speckle tracking echocardiographic parameter, can detect subtle subclinical cardiac dysfunction in patients with AVD that is not apparent using traditional echocardiographic techniques. The emerging technique of 3D full volume color Doppler echocardiography provides more accurate measurement of the severity of aortic regurgitation than 2D-proximal isovelocity surface area. These novel techniques are promising for evaluating and risk stratifying patients to optimize surgical interventions, predict recovery, and improve clinical outcomes. 展开更多
关键词 aortic STENOSIS aortic REGURGITATION Speckle tracking ECHOCARDIOGRAPHY Strain Torsion Transcatheter aortic VALVE replacement LOW flow LOW gradient aortic STENOSIS 3D ECHOCARDIOGRAPHY
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CT血流储备分数与冠状动脉周围脂肪衰减指数联合临床及冠状动脉CT血管造影特征预测主动脉瓣置换术术后不良心血管事件
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作者 黄书苑 杨宝珠 +1 位作者 于鑫鑫 王锡明 《中国医学影像技术》 CSCD 北大核心 2024年第6期848-852,共5页
目的评估CT血流储备分数(CT-FFR)与冠状动脉周围脂肪衰减指数(FAI)联合临床及冠状动脉CT血管造影(CCTA)特征预测主动脉瓣置换术(AVR)术后发生主要不良心血管事件(MACE)的价值。方法回顾性分析139例接受AVR的主动脉瓣狭窄患者,根据随访... 目的评估CT血流储备分数(CT-FFR)与冠状动脉周围脂肪衰减指数(FAI)联合临床及冠状动脉CT血管造影(CCTA)特征预测主动脉瓣置换术(AVR)术后发生主要不良心血管事件(MACE)的价值。方法回顾性分析139例接受AVR的主动脉瓣狭窄患者,根据随访中是否发生MACE将其分为MACE组与非MACE组;以Cox比例风险回归分析临床、CCTA及冠状动脉CT-FFR、FAI,筛选术后发生MACE的独立预测因素,基于临床、CCTA特征,以及CT-FFR及右冠状动脉(RCA)FAI建立嵌套模型。绘制受试者工作特征(ROC)曲线,计算曲线下面积(AUC)及Harrell C指数,评估各模型诊断效能及其拟合优度。结果MACE组22例、无MACE组117例。CT-FFR(HR=3.683)及RCA-FAI(HR=3.261)均为AVR术后发生MACE的独立预测因素。临床模型、临床+CCTA、临床+CCTA+CT-FFR模型及临床+CCTA+CT-FFR+RCA-FAI模型预测AVR术后MACE的AUC分别为0.636、0.730、0.758及0.817,C指数分别为0.614、0.707、0.733及0.782;其中,临床+CCTA+CT-FFR+RCA-FAI模型预测结果与实际结果的一致性最高、拟合优度最佳。结论CT-FFR及RCA-FAI联合临床及CCTA特征能有效预测AVR术后MACE。 展开更多
关键词 冠状动脉疾病 主动脉瓣狭窄 不良心血管事件 CT血流储备分数 脂肪衰减指数
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基于Flow Simulation的人工机械多叶瓣膜优化与分析
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作者 杨博 王伟 刘进闯 《机械》 2019年第4期22-25,29,共5页
三叶瓣作为标准的中心血流型瓣膜,流体性能优良,却未见广泛应用于临床。从传统的双叶瓣出发,通过使用Solidworks中的Flow Simulation对双叶瓣与三叶瓣进行血液流态分析,设置不同的入口流量以模拟瓣膜在不同心输出环境下的工作状态。通... 三叶瓣作为标准的中心血流型瓣膜,流体性能优良,却未见广泛应用于临床。从传统的双叶瓣出发,通过使用Solidworks中的Flow Simulation对双叶瓣与三叶瓣进行血液流态分析,设置不同的入口流量以模拟瓣膜在不同心输出环境下的工作状态。通过比较双叶瓣膜与三叶瓣膜两者跨瓣压差以及速度分布等性能参数,结果表明三叶瓣流体性能更优良且血液流动更稳定。并以此结论为基础,设计了一种新的三叶瓣结构,测试结果表明新型三叶瓣膜的性能更加优良,速度分布更均匀。可见三叶瓣膜十分具有发展潜力。 展开更多
关键词 主动脉瓣 血液流体分析 人工机械瓣膜 双叶瓣膜 多叶瓣膜
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Finite element analysis of a percutaneous aortic valve stent design
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作者 Gideon Praveen Kumar Lazar Mathew 《Health》 2009年第1期2-7,共6页
Aim: This paper discusses the design and Finite Element Analysis (FEA) of a Percutaneous Aor-tic Valve Stent. The aim of this study was to model a percutaneous aortic valve stent and subject it to finite element analy... Aim: This paper discusses the design and Finite Element Analysis (FEA) of a Percutaneous Aor-tic Valve Stent. The aim of this study was to model a percutaneous aortic valve stent and subject it to finite element analysis. The design process was carried out to meet the functional and surgical requirements. Methods and Results: Analysis was done with different materials with loads ranging from 50 kgf/mm&amp;amp;#178;to 73 kgf/mm&amp;amp;#178;. These forces were selected because these val-ues are far greater than the normal human blood pressure which ranges from 10kPa to 16kPa. It was also to understand the mechanical behavior of different stent materials under such high pressures. A stent model was generated and its physical, mechanical and behavioral properties were studied. Finite element analysis and simulation of the model enhanced the designer to optimize the geometry suitable for perform-ance during and after implantation. The design objective for the stent is to have long term du-rability, low thrombogenicity, resistance to mi-gration and paravalvular leak. Conclusion: The analysis performed in this paper may aid in understanding the stent’s tolerable pressures ranges in comparison with the physiological pressures exerted by the heart and cardiac blood flow during abnormal cardiovascular conditions. 展开更多
关键词 STENT Finite Element Analysis Blood flow aortic VALVE STENOSIS PORT Size
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Evaluation of Stress Strain Patterns in a Stentless Aortic Valve and Its Leaflets
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作者 Gideon Praveen Kumar Lazar Mathew 《Surgical Science》 2011年第1期25-30,共6页
Objective: To design a new trileaflet aortic valve and investigate its mechanical behavior using finite ele- ment methods. Background: Quantification of aortic valve deformation during cardiac cycle is essential in un... Objective: To design a new trileaflet aortic valve and investigate its mechanical behavior using finite ele- ment methods. Background: Quantification of aortic valve deformation during cardiac cycle is essential in understanding normal and pathological valvular function and eventually in the design of valves. We have designed and analyzed a new tissue valve model to investigate the mechanics of the valve and its components. Methods: Steps involves in 3D CAD based geometric modeling of a trileaflet aortic valve and the effects of different component dimensions on the mechanical behavior of valve is presented in this paper. Conceptual designing of individual components was used to build the total geometric model. Different physiological pressures were applied on the valve model and its deformation patterns were studied. Results: A new geometric model of a trileaflet aortic valve was designed. Its mechanical behavior was studied. Geometric analysis and simulation of these models enhanced the designer to optimize the geometry suitable for performance during and after implantation. Conclusion: The geometry-based model presented here allows determining quickly if the new set of valve component dimensions results in a functional valve. This is of great interest to designers of new prosthetic heart valve models, as well as to surgeons involved in valve- sparing surgery. 展开更多
关键词 Blood flow aortic VALVE Mechanics CONCEPTUAL Design Finite Element Analysis
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心肌做功指数联合主动脉峡部血流指数对妊娠期高血压患者胎儿心功能的评估价值 被引量:1
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作者 张楠楠 周恒 +1 位作者 李晓静 宛杨 《临床和实验医学杂志》 2023年第10期1084-1087,共4页
目的探讨心肌做功指数(MPI)联合主动脉峡部血流指数(IFI)对妊娠期高血压(HDP)患者胎儿心功能的评估价值。方法前瞻性选取2021年3月至2022年11月阜阳市人民医院收治的105例HDP患者为研究组,以病情严重程度将其分成妊娠期高血压组38例、... 目的探讨心肌做功指数(MPI)联合主动脉峡部血流指数(IFI)对妊娠期高血压(HDP)患者胎儿心功能的评估价值。方法前瞻性选取2021年3月至2022年11月阜阳市人民医院收治的105例HDP患者为研究组,以病情严重程度将其分成妊娠期高血压组38例、轻度子痫前期组35例、重度子痫前期组32例,另选取同院同时间血压监测正常的孕妇39例为对照组。比较研究组与对照组的一般资料,所有孕妇均接受多普勒超声检测MPI与IFI;比较妊娠期高血压组、轻度子痫前期组、重度子痫前期组、对照组MPI与IFI;分析MPI与IFI的相关性;分析MPI、IFI及二者联合检测对HDP患者胎儿心功能的评估价值。结果研究组与对照组患者年龄、孕周、体重指数比较,差异均无统计学意义(P>0.05)。研究组患者的舒张压、收缩压均明显高于对照组,差异均有统计学意义(P<0.05)。重度子痫前期组MPI明显高于轻度子痫前期组、妊娠期高血压组、对照组,轻度子痫前期组MPI明显高于妊娠期高血压组、对照组,妊娠期高血压组患者MPI明显高于对照组,差异均有统计学意义(P<0.05)。重度子痫前期组IFI明显低于轻度子痫前期组、妊娠期高血压组、对照组,轻度子痫前期组IFI明显低于妊娠期高血压组、对照组,妊娠期高血压组明显IFI低于对照组,差异均有统计学意义(P<0.05)。Pearson分析结果显示,MPI与IFI呈负相关(r=-0.482,P<0.05)。MPI、IFI二者联合检测评估HDP患者胎儿心功能异常的阳性率明显高于单独指标评估的阳性率,差异有统计学意义(P<0.05)。结论随着HDP疾病的进展,MPI明显升高,IFI明显降低,HDP患者的MPI与IFI密切相关,二者均可用于评估HDP患者的胎儿心功能,且二者联合的评估价值更高。 展开更多
关键词 妊娠期高血压 胎儿心功能 心肌做功指数 主动脉峡部血流指数 评估价值
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主动脉瓣狭窄对左心室血流特性的影响
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作者 强彦 李志雄 +4 位作者 韩伟 李仁年 冯慧敏 马小宁 张思聪 《中国医学物理学杂志》 CSCD 2023年第3期384-391,共8页
基于CT断层扫描数据,对心脏左心室进行三维重构和模型优化。结合心肌壁面的运动特性,建立左心室几何模型过流边界运动的数学模型。通过水力半径表征主动脉瓣的狭窄程度,采用动网格技术研究主动脉瓣狭窄对左心室血液流动的影响。研究发... 基于CT断层扫描数据,对心脏左心室进行三维重构和模型优化。结合心肌壁面的运动特性,建立左心室几何模型过流边界运动的数学模型。通过水力半径表征主动脉瓣的狭窄程度,采用动网格技术研究主动脉瓣狭窄对左心室血液流动的影响。研究发现不同程度主动脉瓣狭窄时,水力半径与主动脉瓣狭窄程度负相关,出口面积减小,收缩期出口处速度与压力升高,剪切应力增加。舒张期,速度与压力出现先增大后减小的规律。当水力半径较小时,左心室瓣膜处剪切应力较大,收缩初期剪切应力最大为0.81 Pa。通过动态模拟对心脏的仿真研究,为后续心脏的研究提供重要的参考价值。 展开更多
关键词 左心室 主动脉瓣狭窄 水力半径 血流特性 剪切应力
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人工心脏中的磁浮电机样机研制与控制
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作者 王铭伟 刘泽 +3 位作者 苗宇 赵思泽 黄文超 李俊杰 《传感器与微系统》 CSCD 北大核心 2023年第1期105-108,共4页
目前,临床中广泛应用的心脏血泵存在易形成血栓等问题。磁浮电机定子和转子的无接触转动,能够大大降低溶血几率。针对这一问题,搭建了磁浮血泵试验机,设计了硬件电路和上位机调速控制系统;采用能量密度控制方法,实现了单驱动线圈条件下... 目前,临床中广泛应用的心脏血泵存在易形成血栓等问题。磁浮电机定子和转子的无接触转动,能够大大降低溶血几率。针对这一问题,搭建了磁浮血泵试验机,设计了硬件电路和上位机调速控制系统;采用能量密度控制方法,实现了单驱动线圈条件下的加减速控制;建立人体心脏模型,仿真得出人体心脏主动脉流量曲线,并以此作为电机调速的目标曲线。实验结果证明:本设计中的磁浮电机能够实现无接触转动与人体心脏主动脉流量曲线的跟踪控制。 展开更多
关键词 磁浮电机 能量密度控制 无级调速 主动脉流量曲线
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磁共振成像在慢性主动脉夹层中的临床价值及研究进展 被引量:1
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作者 邓铁 王文静 +2 位作者 余洪 李传明 李邦国 《中国CT和MRI杂志》 2023年第4期181-183,共3页
主动脉夹层(aortic dissection,AD)是急性主动脉综合征(acute aortic syndrome,AAS)的其中一种,其发病急、进展迅速,临床表现复杂多变,具有较高的致死率和致残率,因此快速准确的诊断非常重要,临床上多采用计算机断层扫描(computed tomog... 主动脉夹层(aortic dissection,AD)是急性主动脉综合征(acute aortic syndrome,AAS)的其中一种,其发病急、进展迅速,临床表现复杂多变,具有较高的致死率和致残率,因此快速准确的诊断非常重要,临床上多采用计算机断层扫描(computed tomography,CT)和超声心动图(echocardiography,ECG)进行诊断。虽然慢性主动脉夹层(chronic aortic dissection,CAD)的病程相对较长、病情较为稳定,但可出现严重并发症(包括动脉瘤及假腔血栓的形成),所以针对CAD进行定期检查并监测并发症的发生就显得尤为重要。众所周知,磁共振成像(magnetic resonance imaging,MRI)作为一项能够开展多序列多维度的影像检查技术,在日常工作中对慢性主动脉夹层的评价具有重要意义。本文将对MRI在慢性主动脉夹层诊疗中的临床价值及研究进展进行综述。 展开更多
关键词 慢性主动脉夹层 磁共振 4D-flow 假腔 血栓
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妊娠期糖尿病患者胎儿主动脉峡部血流参数联合血清游离雌三醇、脂联素水平预测胎儿窘迫的价值 被引量:1
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作者 陈立秀 郎朝容 +2 位作者 全余罗 唐庆 祝青 《临床超声医学杂志》 CSCD 2023年第6期465-468,共4页
目的探讨妊娠期糖尿病(GDM)患者胎儿主动脉峡部(AOI)血流参数联合血清游离雌三醇(FE3)、脂联素(ADP)水平预测胎儿窘迫(FD)的价值。方法选取我院300例GDM患者,根据是否发生FD分为FD组74例和非FD组226例,另选同期正常妊娠者75例为对照组,... 目的探讨妊娠期糖尿病(GDM)患者胎儿主动脉峡部(AOI)血流参数联合血清游离雌三醇(FE3)、脂联素(ADP)水平预测胎儿窘迫(FD)的价值。方法选取我院300例GDM患者,根据是否发生FD分为FD组74例和非FD组226例,另选同期正常妊娠者75例为对照组,比较各组胎儿AOI血流参数[血流指数(IFI)、收缩指数(ISI)]及血清FE3、ADP水平的差异。应用Pearson相关分析法分析血清FE3、ADP水平与胎儿IFI、ISI的关系;绘制受试者工作特征(ROC)曲线分析GDM患者胎儿IFI、ISI和血清FE3、ADP水平单独及联合应用预测FD的效能。结果FD组血清FE3、ADP水平及胎儿IFI均低于非FD组和对照组,胎儿ISI高于非FD组和对照组,差异均有统计学意义(均P<0.05);非FD组血清FE3、ADP水平及胎儿IFI均低于对照组,胎儿ISI高于对照组,差异均有统计学意义(均P<0.05)。Pearson相关分析显示,GDM患者血清FE3水平与胎儿IFI呈正相关(r=0.553,P<0.01),与胎儿ISI呈负相关(r=-0.488,P<0.01);血清ADP水平与胎儿IFI呈正相关(r=0.547,P<0.01),与胎儿ISI呈负相关(r=-0.464,P<0.01)。ROC曲线分析显示,GDM患者胎儿IFI、ISI和血清FE3、ADP水平单独及联合应用预测FD的曲线下面积(AUC)分别为0.711、0.642、0.690、0.811、0.947,血清ADP水平的AUC高于血清FE3水平和胎儿ISI(Z=3.511、3.185,均P<0.05),联合应用预测的AUC高于血清FE3水平和胎儿IFI、ISI(Z=6.952、6.019、9.078,均P<0.05)。结论GDM患者胎儿AOI血流参数IFI、ISI联合血清FE3、ADP水平在预测FD中具有重要价值。 展开更多
关键词 超声检查 妊娠期糖尿病 游离雌三醇 脂联素 主动脉峡部 血流参数 胎儿窘迫
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经鼻高流量湿化氧疗结合一氧化氮吸入对急性A型主动脉夹层术后低氧血症的临床价值研究
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作者 温彩云 糜小静 +3 位作者 邱倩 刘子由 陈洪 段志胜 《中国医学创新》 CAS 2023年第25期20-24,共5页
目的:探究急性A型主动脉夹层术后低氧血症患者采用经鼻高流量湿化氧疗结合一氧化氮(NO)吸入治疗的临床效果。方法:选取2020年1月—2022年9月赣南医学院第一附属医院收治的98例急性A型主动脉夹层术后低氧血症患者作为研究对象,依据治疗... 目的:探究急性A型主动脉夹层术后低氧血症患者采用经鼻高流量湿化氧疗结合一氧化氮(NO)吸入治疗的临床效果。方法:选取2020年1月—2022年9月赣南医学院第一附属医院收治的98例急性A型主动脉夹层术后低氧血症患者作为研究对象,依据治疗方案不同将其分为对照组与观察组,每组49例,对照组采用NO吸入治疗,观察组在对照组基础上同时联合经鼻高流量湿化氧疗治疗,对比两组临床指标、住院时间、机械通气率、28 d病死率、并发症发生率。结果:两组治疗前(T_(0))临床指标对比差异均无统计学意义(P>0.05);观察组治疗2 h(T_(1))、治疗12 h(T_(2))、治疗24 h(T_(3))时呼吸频率(RR)均高于对照组,治疗48 h(T_(4))时低于对照组,差异均有统计学意义(P<0.05);观察组T_(1)、T_(2)、T_(3)、T_(4)时经皮动脉血氧饱和度(SpO_(2))均高于对照组,差异均有统计学意义(P<0.05)。观察组T_(1)、T_(2)、T_(4)时氧合指数(PaO_(2)/FiO_(2))均高于对照组,T_(3)时低于对照组,差异均有统计学意义(P<0.05)。观察组T_(1)、T_(4)时二氧化碳分压(PaCO_(2))均高于对照组,T_(2)、T_(3)时均低于对照组,差异均有统计学意义(P<0.05)。观察组治疗后住院时间短于对照组,观察组治疗后机械通气率、28 d病死率、并发症发生率均低于对照组,差异均有统计学意义(P<0.05)。结论:急性A型主动脉夹层术后低氧血症患者治疗时,经鼻高流量湿化氧疗结合NO吸入治疗,可显著减少并发症,有利于预后。 展开更多
关键词 急性A型主动脉夹层 低氧血症 经鼻高流量湿化氧疗 一氧化氮吸入治疗
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降粘抗栓片I号对犬冠脉流量的影响 被引量:11
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作者 王宗仁 罗晓星 +6 位作者 陈学福 夏天 方坤泉 马世平 朱海龙 祝恒山 石磊 《第四军医大学学报》 1996年第6期424-426,共3页
目的:研究中药复方制剂降粘抗栓片I号混悬液对急性心肌缺血犬的冠脉、主动脉血流量及心率的影响.方法:用犬作为实验对象,采用冠脉结扎技术,造成麻醉犬急性心肌缺血模型的实验方法.结果:降粘抗栓片I号中药制剂能减少冠脉结扎后... 目的:研究中药复方制剂降粘抗栓片I号混悬液对急性心肌缺血犬的冠脉、主动脉血流量及心率的影响.方法:用犬作为实验对象,采用冠脉结扎技术,造成麻醉犬急性心肌缺血模型的实验方法.结果:降粘抗栓片I号中药制剂能减少冠脉结扎后的冠脉流量下降(P<0.05)和主动脉流量的下降程度(P<0.05);有维持冠脉结扎后的心率作用.结论:降粘抗栓片I号有治疗和预防缺血性心脏病的作用. 展开更多
关键词 降粘抗栓片 冠脉流量 中药药理学
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