Laboratory of Cardiovascular BiomechanicsHynek Chlup
The Laboratory of Cardiovascular Biomechanics forms a part of the Department of Mechanics, Biomechanics and Mechatronics at the Faculty of Mechanical Engineering, Czech Technical University in Prague. The laboratory is supported by projects of the Czech Ministry of Education and Grant Agency of the Czech Republic.
The research is focused on basic and applied topics in cardiovascular biomechanics. Our recent projects mostly involve studies of mechanical response of blood vessel to external loading. Our laboratory is equipped with an experimental set-up simulating human circulation with computer-controlled SuperPump pulsator. The software controls pressure waveform and frequency. Adjustable systemic resistor can be added to the circuit. It consists of numerous flow splits and capillary resistance segments. The set-up is used for detecting the pulse wave velocity in large arteries and for identifying the material properties of the arterial wall. It can also be used for investigation of properties of artificial valves, shunts and stents. The set-up is modular hence it can be adjusted on demand according to specific requirements. In general, it can be utilized in determining mechanical properties of elastic tubes loaded by pulsatile flow, external pressure or axial pretension. The set-up is equipped with Cressto pressure sensors (0-10 kPa, 0-25 kPa, 0-200 kPa, 0-500 kPa, 0-2.5 MPa) and Kulite probes (0-250kPa). Flow rates are measured by the HiDop 300 Doppler ultrasound device or UVP monitor MetFlow. Oscilloscop LeCroy can also be employed.
Another experimental device is the set-up designed for self-excited oscillations in elastic tubes. It contains hydrodynamic pump that generates continual flow, stilling chambers for calming disturbances in the flow in front of and behind a specimen. The specimen is attached in the experimental chamber where external pressure and axial pretension can be applied.
Mentioned set-ups can also be used for static inflation-extension tests of elastic tubes with inner diameters in the range of 3 - 30 mm.
Kinematics of traveling waves or inflated and extended tubes is recorded via several displacements sensors. High precision confocal optical sensors Precitec CHRocodile M4 (4 pc.) with working range up to 6mm, high speed laser profile measurement sensor micro-epsilon scanCONTROL 2800 and laser point sensors micro-epsilon optoNCDT 2200-50 and 2200-100. The laboratory is also equipped with universal 3D digital correlation system DANTEC Q-450.
Moreover, the laboratory has been newly equipped with Biaxial tensile testing system for experimental determination of constitutitve behavior of anisotropic materials - Messphysik biaxial tesing machine.
Fluid flow phenomena are also studied by a dispersion of conductive chemicals in the fluid flow. The MSV 66, INSA conductometer is used in our laboratory. It can be used in simple or split tube systems with a rigid or elastic wall.
The experimental results are processed in MatLab, Maple, FEMINA, Microsoft Visual Studio and FORTRAN programs. Digital image analysis (e.g. histomorphometrical assessment) can be carried out with in-house BinaryDirection or with NIS Elements. FEM or FVM simulations are provided in ANSYS, Abaqus or in-house FELIB and FEMINA.
- Project IGA MZ CR Optimization of physical properties of artery wall grafts for low flow rates
Project GA108/10/1296 - Development and Characterization of Active Hybrid Textiles with Integrated Nanograin NiTi Micro Wires (2008-2011, GA0/GA)
- SGS ČVUT 2010 OHK2-005/10 - Research of technical and biological composite materials (2010-2012)
- Project FRVS 90/2010 Physical model of the vascular system - dispersion of substances (2010)
- Project GA106/08/0557 - Material properties of veins and their remodelling (2008-2011, GA0/GA)
- CTU development project, Development of common instrumentation platform in biomedical engineering, (2008-2009)
- Institutional research plan MSM6840770012 - Transdisciplinary Research in the Field of Biomedical Engineering II (2005-2011, MSM)
- Project GA106/04/1181 - Identification of the vessel wall materials properties (2004-2006, GA0/GA)
- Institutional research plan MSM 210000012 - Transdisciplinary Biomedical Engineering Research (1999-2004, MSM)
Horny L, Adamek T, Kulvajtova M (2013) Analysis of axial prestretch in the abdominal aorta with reference to post mortem interval and degree of atherosclerosis. Journal of the Mechanical Behavior of Biomedical Materials, in press. doi: 10.1016/j.jmbbm.2013.01.033
Horny, L., Adamek, T., & Zitny, R. (2013) Age-related changes in longitudinal prestress in human abdominal aorta. Archive of Applied Mechanics 83(6):875-888. doi: 10.1007/s00419-012-0723-4
L. Horny, J. Vesely, H. Chlup, K. Janouchova, M. Vyšanská (2012) Single fiber pull-out test of nitinol-silicon-textile composite. Bulletin of Applied Mechanics 8:77-80.
L. Horny (2012) How ageing is reflected by longitudinal pretension in human abdominal aorta. PhD thesis, Czech Technical University in Prague.
H. Chlup, P. Novotny, R. Zitny (2012) Accuracy of tracer stimulus response experiments in laminar flows. International Journal of Heat and Mass Transfer 55:6458-6462. doi: 10.1016/j.ijheatmasstransfer.2012.06.042
L. Horny, T. Adamek, H. Chlup, R. Zitny, J. Vesely, E. Gultova, J. Kronek, D. Hromadka (2012) Longitudinal prestretch in human infrarenal aorta. Journal of Biomechanics 45(Supp.1):S24. DOI: 10.1016/S0021-9290(12)70025-8
L. Horny, H. Chlup, R. Zitny, T. Vonavkova, J. Vesely, P. Lanzer (2012) Ex vivo coronary stent implantation evaluated with digital image correlation. Experimental Mechanics 52(9):1555-1558. DOI: 10.1007/s11340-012-9620-6
L. Horny, T. Adamek, H. Chlup, R. Zitny (2012) Age estimation based on a combined arteriosclerotic index. International Journal of Legal Medicine, 126(2):321-326. DOI: 10.1007/s00414-011-0653-7
L. Horny, T. Adamek, J. Vesely, H. Chlup, R. Zitny and S. Konvickova (2012) Age-related distribution of longitudinal pre-strain in abdominal aorta with emphasis on forensic application. Forensic Science International, 214(1-3):18-22. DOI: 10.1016/j.forsciint.2011.07.007
E. Gultova, L. Horny, H. Chup, R. Zitny (2011) A comparison between the exponential and limiting fiber extensibility pseudoelastic model for the Mullins effect in arterial tissue. Journal of Theoretical and Applied Mechanics, 49:1203-1216.
L. Horny, T. Adamek, E. Gultova, R. Zitny, J. Vesely, H. Chlup and S. Konvickova (2011) Correlations between age, prestrain, diameter and atherosclerosis in the male abdominal aorta. Journal of the Mechanical Behavior of Biomedical Materials 4(8):2128-2132. DOI: 10.1016/j.jmbbm.2011.07.011
L. Horny, H. Chlup, J. Kronek, E. Gultova, L. Heller, R. Zitny and D. Vokoun (2011) Inflation-Extension Test of Silicon Rubber-Nitinol Composite Tube. IFMBE Proceedings 37:1027-1030. DOI: 10.1007/978-3-642-23508-5_267
L. Horny, H. Chlup, J. Vesely, E. Gultova, J. Kronek, R. Zitny, T. Vonavkova, T. Adamek, P. Lanzer, D. Hromadka (2011) In vitro Coronary Stent Implantation: Vessel Wall-Stent Interaction. IFMBE Proceedings 37:795-798. DOI: 10.1007/978-3-642-23508-5_207
L. Horny, E. Gultova, T. Adamek, R. Zitny, H. Chlup (2011) In Situ Longitudinal Pretension in Human Aorta. IFMBE Proceedings 37:430-433. DOI:10.1007/978-3-642-23508-5_112
Vesely, J., Horny, L., Chlup, H., & Zitny, R. (2011). Collagen orientation and waviness within the vein wall. Paper presented at the Computational Plasticity XI - Fundamentals and Applications, COMPLAS XI, 720-728.
Gultova, E., Horny, L., Chlup, H., & Zitny, R. (2011). An anisotropic pseudo-elastic model for the mullins effect in arterial tissue. Paper presented at the Computational Plasticity XI - Fundamentals and Applications, COMPLAS XI, 713-719.
Horný, L., Chlup, T. A., Žitný, R., Gultová, E., & Veselý, J. (2011). Longitudinal prestrain in male abdominal aorta from pulse wave velocity viewpoint. Paper presented at the Computational Plasticity XI - Fundamentals and Applications, COMPLAS XI, 757-763.
L. Horny, E. Gultova, H. Chlup, R. Sedlacek, J. Kronek, J. Vesely and R. Zitny (2010) Mullins effect in human aorta described with limiting extensibility evolution. IFMBE Proceedings, vol. 29, p. 768-771
L. Horny, J. Kronek, H. Chlup, R. Zitny and M. Hulan (2010) A distribution of collagen fiber orientations in aortic histological section. IFMBE Proceedings, vol. 29, p. 772-775
J. Kronek, R. Žitný, L. Horný, H. Chlup, M. Beran (2010) Mechanical properties of artery-artery connection based upon transglutaminase cross-linked collagen. Metalurgija, vol. 49, no. 2, p. 356-360
L. Horný, H. Chlup, R. Žitný, T. Adámek (2010) Constitutive modeling of coronary artery bypass graft with incorporated torsion. vol. 49, no. 2, p. 273-277
L. Horny, E. Gultova, H. Chlup, R. Sedlacek, J. Kronek, J. Vesely and R. Zitny (2010) The Mullins effect in aorta and limiting extensibility evolution. Bulletin of Applied Mechanics, vol. 6, no. 21, p. 1-5
L. Horny, J. Kronek, H. Chlup, R. Zitny, J. Vesely and M. Hulan (2010) Orientations of collagen fibers in aortic histological section. Bulletin of Applied Mechanics, vol. 6, no. 22, p. 25-29
L. Horny, M. Hulan, R. Zitny, H. Chlup, S. Konvickova and T. Adamek (2009) Computer-Aided Analysis of Arterial Wall Architecture. IFMBE Proceedings, vol. 25/4, p. 1494-1497
L. Horny, H. Chlup, R. Zitny, S. Konvickova and Tomas Adamek (2009) Constitutive Behavior of Coronary Artery Bypass Graft. IFMBE Proceedings, vol. 25/4, p. 181-184
L. Horny, R. Zitny and H. Chlup (2008) Strain energy function for arterial walls based on limiting fiber extensibility. IFMBE Proceedings, vol. 22, p. 1910-1913
H. Macková, H. Chlup, R. Žitný (2007) Numerical model for verification of constitutive laws of blood vessel wall. Journal of Biomechanical Science and Engineering, vol. 2, no. suppl. 1, p. S66
L. Horny, R. Zitny, H. Chlup and H. Mackova (2006) Identification material parameters of an aortic wall. Bulletin Appl Mechan, vol. 2, p. 173–182
H. Chlup, H. Macková, M. Vilímek, P. Kubový, R. Žitný, S. Konvičková (2006) Pulse wave velocity in elastic tube. In: Proceedings of the IASTED International Conference on Modelling, Identification, and Control, 2006, p. 484-488
Applied results of the development
M. Hulan, H. Chlup (2009) Imcontour 7. Result type R: Software for image analysis in digital histomorphometry.
R. Žitný, L. Horný (2009) BIOMAT 2. Result type R: Software for the estimation of parameters in nonlinear and anisotropic constitutive models.
H. Chlup, L. Horný (2008) Přípravek pro detekci zbytkové deformace v tepenné stěně. Result type F: the device for experimental measurement of residual strain in a blood vessel wall. Utility model registered by Industrial Property Office of the Czech Republic.
R. Žitný (2008) FEMINA 1D. Reslut type R: General multipurpose software for 1D FEM and FVM analyses in biomechanics.
Courseware (in Czech only)
Biomechanics I (Cardiovascular solid mechanics)
How to get to the lab
Project GA106/08/0557 - Material properties of veins and their remodeling is carried out in co-operation with Institute of Thermomechanics AS CR, vvi.
Project GA106/08/0557 - Material properties of veins and their remodeling is carried out in co-operation with the Department of Forensic Medicine of the Third Faculty of Medicine Charles University in Prague.
Project GA108/10/1296 - Development and Characterization of Active Hybrid Textiles with Integrated Nanograin NiTi Micro Wires is carried out in co-operations with the Institute of Physics AS CR, vvi (Department of Functional Materials).
We are engaged in optimization of tissue-engineering materials with the Institute of Physiology AS CR, vvi (Department of Growth and Differentiation of Cell Populations, and Institute for Clinical and Experimental Medicine).
Optimization of aortic valve bioreactor and tissue-engineered valve replacement - Institute for Clinical and Experimental Medicine (and Institute of Physiology AS CR).
Since November 2012
Projects in realisation
- Pulsatile flow in cardiovascular system
- Research of technical and biological composite materials
- Relationship between blood vessel wall architecture and constitutive behavior
- Influence of inhomogeneities on the mechanical behavior of blood vessels - bifurcations
- Constitutive modeling of blood vessels
- The corrosive potential as a marker of endoprosthesis failure
- Biotribology of joint replacements
- Wear of thumb joint replacement
- Stent-artery wall interaction
- Mullins effect within cyclic loading of blood vessel walls
- Axial dispersion in the cardiovascular system
- Simulation of self-excited oscillation and forced oscillation of elastic thin-walled pipes and blood vessels
- Biaxial testing machine for soft tissue and elastomer mechanical testing
- Biomechanics of aging of elstic arteries
- Laser position sensors micro-epsilon 2200-50/100
- Pressure transducers