Project Enthral
The main objective of the project is to develop a non invasive technique of assessing the stiffness of the carotid arthery. This will be achieved through originally designed experriments and advanced numerical simulations executed by a team of engineers representing various disciplines and supported by medical doctors.
The project objectives
are defined as:
Development of a method for estimating local material properties of arterial walls from non-invasive in-vivo measurements
Development of 3D numerical model of blood flow within a deforming vessel
Validation of the model using a test rig
Comparison with existing 1D model developed by NTNU
Inverse analysis aimed at retrieving the stiffness of the vessel
Application of the developed methodology to retrieving the stiffness of the carotid artery
Stiffness of arteries wall
- subject background
- subject background
With aging there is a noticeable increase in the stiffness of arteries. Arteries tend to accumulate less elastic potential energy as stiffness increases, they are less elastic. Heart is forced to overperform to compensate for the decreased outflow from arteries, which leads to left ventricular hypertrophy.
Amplified pressure waves leaving the heart are reaching very fine tissues located in kidneys or the brain, leading to their potential destruction.
Pulse pressure and wave reflection
Increasing arterial stiffness leads to a change in the behaviour of the reflected wave. The reflected wave returns to the heart at a shorter time then in healthy subjects.
vanVarik BJ, Rennenberg RJMW, Reutelingsperger CP, Kroon AA, deLeeuw PW and Schurgers LJ (2012) Mechanisms of arterial remodeling: lessons from genetic diseases. Front.Gene. 3:290
This return usually collides with systole which leads to superposition of the reflected and outgoing wave yelding higher pressure than in healthy subjects. Such reinforced waves also make their way to delicate organs potentially causing damage.
Left Common Carotid Artery
The left common carotid artery is the longest branch of the aortic arch. It is a large and elastic channel that arises in the thorax from the arch of the aorta. It can be used to measure the pulse.
Why it matters?
Some cardiovascular diseases may locally change the stiffness of the arteries – a stronger spatial variation in the distensibility of the carotid has been shown in hypertensive patients compared to healthy subject.
Although the changes in the stiffness of the vascular system with age affect the whole vasculature, arteries at different sites respond differently to aging, hypertension, and pregnancy.
Methods of non-invasive evaluation of the local stiffness are often of interest in diagnostics of the arterial system.
Therefore, assessment of the stiffness of the arterial system is a valuable diagnostic index, it serves as a predictor of cardiovascular diseases.
6 working packages
Project has been divided into 6 work packages (WPs):
WP 1 Physical experiment
Wojciech Adamczyk, PhD, DSc
WP 2 Direct models (1D STARFiSh and 3D CFD), comparison of solutions
Ziemowit Ostrowski, PhD, DSc
WP 3 Validation, sensitivity analysis and uncertainty quantification
Jacob Sturdy, PhD
WP 4 Inverse analysis applied to the results of the physical experiment
Prof. Ryszard Białecki
WP 5 Medical experiment
Adam Golda, MD
WP 6 Inverse analysis of medical data
Prof. Leif Rune Hellevik
WP 1
Physical
experiment
WP lead:
- Experimental rig (phantom)
- Physical experiment
WP 3
Validation
WP lead:
- Uncertainly quantification
- Validation
- Sensivity analysis
WP 5
Medical
experiment
WP lead:
- Medical experiment
WP 4
Inverse
analysis
WP lead:
- Inverse solution
- Phantom experiment generated data
WP 2
Lab
models
WP lead:
- Development of 1D and 3D FSI model
WP 6
Inverse analysis of medical data
WP lead:
- Inverse solution
- Medical data
Combined efforts
The experiments concerning the stiffness of the deformable artery imitation will be accompanied by an extensive numerical analysis involving methods used in inverse problems.
The numerical procedure will be built using data collected from the experiments and it will be subsequently used to obtain a reduced-order model that will try to recapture the complexity of the artery’s behaviour, while remaining computationally cost-efficient.
Simplified scheme
of the experimental rig
Experimental site will be prepared in the form of an aquarium filled with ballistic gel.
Project tests phase - medical experiment
The final stage of the project will involve USG measurements performed on live subjects (healthy volunteers) that will be carried out in Gliwice Municipal Hospital Number 4 under supervision of Adam Golda, M.D.
More about us
Our cooperation was possible thanks to Norway grants which funded 85% of project budget and to Polish government which supported project by funding 15% of total budget.
Thanks to them, it was possible for us to arrange our consortium which is combination of some very talented and highly specialised crews from: