1
|
Zhang R, Zhang Y. Experimental analysis of pulsatile flow characteristics in prosthetic aortic valve models with stenosis. Med Eng Phys 2020; 79:10-18. [PMID: 32205024 DOI: 10.1016/j.medengphy.2020.03.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 01/09/2020] [Accepted: 03/10/2020] [Indexed: 11/29/2022]
Abstract
Bioprosthetic valves are widely used for aortic valve replacements for patients with severe aortic diseases. However, tissue-engineered leaflets normally deteriorate over time due to calcification, leading to life-threatening conditions that would require re-operation. The hemodynamics induced by a prosthetic stenosis is complicated and not fully understood. This in vitro experimental study focuses on the fluid dynamics of two aortic valve models with different prosthetic stenosis conditions. An in vitro cardiovascular flow simulator was utilized to provide the pulsatile physiological flow conditions. Phase-locked particle image velocimetry (PIV) and high-frequency pressure sensors were employed to measure the flow fields and pressure waveforms. Pressure data were evaluated for the two models representing moderate and severe stenosis conditions, respectively. The severe prosthetic stenosis induced a prolonged ejection period and increased acceleration time ratio. PIV results suggest the severe prosthetic stenosis resulted in a two-fold increase in peak jet velocity and a three-fold increase in peak turbulence kinetic energy compared to the moderate stenosis case. The severe stenosis also caused rapid expansion of the jet downstream of the valve orifice and increased eccentricity of the jet flow. The maximum Reynolds shear stress in the severe stenosis case was found similar to the bileaflet mechanical valve reported by previous literature, which was below the risk threshold of blood cell damage but could potentially increase the risks of platelet activation and aggregation.
Collapse
Affiliation(s)
- Ruihang Zhang
- Department of Mechanical Engineering, North Dakota State University, Dept 2490, PO Box 6050, Fargo, ND 58103, USA
| | - Yan Zhang
- Department of Mechanical Engineering, North Dakota State University, Dept 2490, PO Box 6050, Fargo, ND 58103, USA.
| |
Collapse
|
2
|
Kheradvar A, Groves EM, Falahatpisheh A, Mofrad MK, Hamed Alavi S, Tranquillo R, Dasi LP, Simmons CA, Jane Grande-Allen K, Goergen CJ, Baaijens F, Little SH, Canic S, Griffith B. Emerging Trends in Heart Valve Engineering: Part IV. Computational Modeling and Experimental Studies. Ann Biomed Eng 2015. [PMID: 26224522 DOI: 10.1007/s10439-015-1394-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
In this final portion of an extensive review of heart valve engineering, we focus on the computational methods and experimental studies related to heart valves. The discussion begins with a thorough review of computational modeling and the governing equations of fluid and structural interaction. We then move onto multiscale and disease specific modeling. Finally, advanced methods related to in vitro testing of the heart valves are reviewed. This section of the review series is intended to illustrate application of computational methods and experimental studies and their interrelation for studying heart valves.
Collapse
Affiliation(s)
- Arash Kheradvar
- Department of Biomedical Engineering, The Edwards Lifesciences Center for Advanced Cardiovascular Technology, University of California, Irvine, 2410 Engineering Hall, Irvine, CA, 92697-2730, USA. .,Department of Medicine, Division of Cardiology, University of California, Irvine School of Medicine, Irvine, CA, USA.
| | - Elliott M Groves
- Department of Biomedical Engineering, The Edwards Lifesciences Center for Advanced Cardiovascular Technology, University of California, Irvine, 2410 Engineering Hall, Irvine, CA, 92697-2730, USA.,Department of Medicine, Division of Cardiology, University of California, Irvine School of Medicine, Irvine, CA, USA
| | - Ahmad Falahatpisheh
- Department of Biomedical Engineering, The Edwards Lifesciences Center for Advanced Cardiovascular Technology, University of California, Irvine, 2410 Engineering Hall, Irvine, CA, 92697-2730, USA
| | - Mohammad K Mofrad
- Department of Bioengineering and Mechanical Engineering, University of California, Berkeley, CA, USA
| | - S Hamed Alavi
- Department of Biomedical Engineering, The Edwards Lifesciences Center for Advanced Cardiovascular Technology, University of California, Irvine, 2410 Engineering Hall, Irvine, CA, 92697-2730, USA
| | - Robert Tranquillo
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Lakshmi P Dasi
- Department of Mechanical Engineering, School of Biomedical Engineering, Colorado State University, Fort Collins, CO, USA
| | - Craig A Simmons
- Department of Mechanical & Industrial Engineering, University of Toronto, Toronto, ON, Canada.,Institute of Biomaterials & Biomedical Engineering, University of Toronto, Toronto, ON, Canada
| | | | - Craig J Goergen
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - Frank Baaijens
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Stephen H Little
- Houston Methodist DeBakey Heart & Vascular Center, Houston, TX, USA
| | - Suncica Canic
- Department of Mathematics, University of Houston, Houston, TX, USA
| | - Boyce Griffith
- Department of Mathematics, Center for Interdisciplinary Applied Mathematics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.,McAllister Heart Institute, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA
| |
Collapse
|
4
|
Hariharan P, Giarra M, Reddy V, Day SW, Manning KB, Deutsch S, Stewart SFC, Myers MR, Berman MR, Burgreen GW, Paterson EG, Malinauskas RA. Multilaboratory particle image velocimetry analysis of the FDA benchmark nozzle model to support validation of computational fluid dynamics simulations. J Biomech Eng 2011; 133:041002. [PMID: 21428676 DOI: 10.1115/1.4003440] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This study is part of a FDA-sponsored project to evaluate the use and limitations of computational fluid dynamics (CFD) in assessing blood flow parameters related to medical device safety. In an interlaboratory study, fluid velocities and pressures were measured in a nozzle model to provide experimental validation for a companion round-robin CFD study. The simple benchmark nozzle model, which mimicked the flow fields in several medical devices, consisted of a gradual flow constriction, a narrow throat region, and a sudden expansion region where a fluid jet exited the center of the nozzle with recirculation zones near the model walls. Measurements of mean velocity and turbulent flow quantities were made in the benchmark device at three independent laboratories using particle image velocimetry (PIV). Flow measurements were performed over a range of nozzle throat Reynolds numbers (Re(throat)) from 500 to 6500, covering the laminar, transitional, and turbulent flow regimes. A standard operating procedure was developed for performing experiments under controlled temperature and flow conditions and for minimizing systematic errors during PIV image acquisition and processing. For laminar (Re(throat)=500) and turbulent flow conditions (Re(throat)≥3500), the velocities measured by the three laboratories were similar with an interlaboratory uncertainty of ∼10% at most of the locations. However, for the transitional flow case (Re(throat)=2000), the uncertainty in the size and the velocity of the jet at the nozzle exit increased to ∼60% and was very sensitive to the flow conditions. An error analysis showed that by minimizing the variability in the experimental parameters such as flow rate and fluid viscosity to less than 5% and by matching the inlet turbulence level between the laboratories, the uncertainties in the velocities of the transitional flow case could be reduced to ∼15%. The experimental procedure and flow results from this interlaboratory study (available at http://fdacfd.nci.nih.gov) will be useful in validating CFD simulations of the benchmark nozzle model and in performing PIV studies on other medical device models.
Collapse
|
6
|
Nobili M, Morbiducci U, Ponzini R, Del Gaudio C, Balducci A, Grigioni M, Maria Montevecchi F, Redaelli A. Numerical simulation of the dynamics of a bileaflet prosthetic heart valve using a fluid–structure interaction approach. J Biomech 2008; 41:2539-50. [DOI: 10.1016/j.jbiomech.2008.05.004] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2007] [Revised: 04/04/2008] [Accepted: 05/06/2008] [Indexed: 10/21/2022]
|