Biomechanics III (FSI-RBM-A)

Academic year 2020/2021

Supervisor:	prof. Ing. Jiří Burša, Ph.D.
Supervising institute:	ÚMTMB	all courses guaranted by this institute
Teaching language:	English
Aims of the course unit:
The enlarge the knowledge from the course in Biomechanics I about properties of cardiovascular system elements and implants, especially about those important for mechanics. Students are made familiar with modelling of mechanical behaviour of these elements at the level corresponding to the actual state of science and to the possibilities of existing hardware and software. They get familiar with implants applied in the cardio-vascular system and principals of their design.
Learning outcomes and competences:
Students will have a clear idea of basic biomechanical problems of cardiovascular system and of the implants used in it. They will be able to model these problems at the actual level of scientific knowledge and of technological equipment. They deepen their skills in computational modelling of many specific material properties of advanced materials used in technology (anisotropic, viscoelasticitic, hyperelastic models of materials, as well as shape memory alloys). They get acquainted with computational modelling of non-Newtonian liquids and their flow in compliant tubes (fluid-structure interaction).
Prerequisites:
Knowledge of basic terms of theory of elasticity and selected theories in the range of the course 5PP-A (stress, strain, general Hooke's law, membrane theory of shells, thick-wall cylindrical vessel). Knowledge of basic medical terms and structure of cardio-vascular system at the level ot the course Biomechanics I. Description of mechanical properties of materials under large strains using hyperelastic constitutive models including anisotropic ones. Basic properties of Newtonian liquids (viscosity), theory of linear viscoelasticity. Fundamentals of FEM and basic handling of ANSYS system.
Course contents:
The course aims at deeper understanding of biomechanical problems in cardio-vascular system. It presents overview of mechanical properties of its elements, analysis of their importance from the point of view of biomechanics and possible ways of their computational modelling. It deals with specific models of soft tissues (material non-linearity, anisotropic hyperelasticity, active contraction) based on description of their fibrous non-homogeneous structure. It presents the mechanical structure of animal cell and principles of its modelling. It offers an overview of basic reological properties of blood and modelling of pulsatile flow in a compliant tube. . Further, man-made replacements used in cardio-vascular surgery are dealt with (artificial cardiac pumps, heart valves, arterial stents, vascular grafts). It deals with their construction principles, specific requirements and materials and possibilities of improvement of their properties. Possibilities of exploitation of ANSYS software in cardiovascular mechanics and its limitations are presented.
Teaching methods and criteria:
The course is taught through lectures explaining the basic principles and theory of the discipline. Seminars are focused on practical exercising of the topics presented in lectures.
Assesment methods and criteria linked to learning outcomes:
Active participation in seminars, final project and its defence, test of basic theoretical knowledge.
Controlled participation in lessons:
Attendance at practical training is obligatory. An apologized absence can be compensed by individual projects controlled by the tutor.
Type of course unit:
Lecture	13 × 2 hrs.	optionally
Computer-assisted exercise	13 × 1 hrs.	compulsory
Course curriculum:
Lecture	1.Introduction, contents of the course, mechanical properties of arteries and their experimental evaluation. 2. Definition of cardio-vascular system, fundamentals of its anatomy. 3. Fundamentals of physiological processes in heart and blood vessels, residual stress in arteries. 4. Structure and rheological properties of blood, models of blood behaviour, velocity profiles of non-Newtonean liquids, Fahraeus-Lindqvist effect. 5. Structure and components of vascular and myocardial walls, mechanical properties of components. 6. Constitutive models of soft tissues based on structural arrangement of collagen fibres. 7. Mechanical properties of cells, cytoskeleton and its computational modelling as a tensegrity structure. 8. Mechanical influence on atherosclerotic processes, principals of treatments. 9. Arterial stents, principals of function, design and production. 10. Systemization of replacements of organs, transplants, vascular grafts, their types, properties, aplication and production. 11.Natural and artificial heart valves, principals of function, overview of products. 12.Ventricular assist devices and total artificial hearts. 13.Actual possibilities of FEM in modelling of heart and blood vessels.

Computer-assisted exercise	Calculation of parameters of blood flow and analytical computations of stress in blood vessel wall - limitations. Isotropic hyperelastic constitutive models of arterial wall, residual stress. Alternative appproaches to calculation of residual stresses in arterial wall. Computational modelling of flow in a compliant artery -fluid-structure interaction. Tensegrity-based computational model of cell cytoskeleton. Anisotropic model of contraction of left heart ventricle. Formulation of semester projects for course unit credit.

Literature - fundamental:
1. Cardiovascular solid mechanics. Cells, Tissues and Organs.Springer, 2002.
2. Biomechanics. Mechanical properties of living tissues.Springer, 1993.
3. Křen J., Rosenberg J., Janíček P.: Biomechanika
Literature - recommended:
1. Křen J., Rosenberg J., Janíček P.: Biomechanika
2. Valenta a kol.: Biomechanika srdečně cévního systému
3. Čihák R.: Anatomie