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valvular heart diseases cause obstruction of the antegrade flow (stenosis), failure of the retrograde flow (insufficiency), or a combination of both. Severe valvular pathologies are usually addressed surgically by repairing or replacing the affected valve using an artificial valve substitute [1, 52]. Almost 300,000 heart valve operations are performed worldwide annually [55]. There are two principal types of heart valve substitutes, which are widely used in cardiac surgery: mechanical prosthetic valves from nonbiologic material (polymer, metal, carbon) or biological

References 1. Duran CG. [the Behavior of Aortic Valve Homo-grafts in Man and Animals]. Coeur Med Interne. 1964 Jul;64:301-5. 2. Simionescu DT, Chen J, Jaeggli M, Wang B, Liao J. Form Follows Function: Advances in Trilayered Structure Replication for Aortic Heart Valve Tissue Engineering. J Healthc Eng. 2012 Jun;3(2):179-202. DOI: 10.1260/2040-2295.3.2.179 3. Zilla P, Human P, Bezuidenhout D. Bioprosthetic heart valves: the need for a quantum leap. Biotechnol Appl Biochem. 2004 Aug;40(Pt 1):57-66. 4. Sohier J, Carubelli I, Sarathchandra P, Latif N, Chester AH

Researches in the field of human cardiovascular system are now in demand as never before. This is caused by two main reasons. First, cardiovascular diseases are becoming more prevalent due to social factors (economical changes, urbanization, etc. lead to changes in lifestyle of many people) and increasing influence of risk factors (e.g., reduced physical activity) [ 1 ]. About 250,000 surgical operations are carried out every year in the world to restore or replace damaged heart valves, and the trend is to increase that number [ 7 ]. Second, in order to improve

Introduction The basis for current tissue engineering concepts for heart valves are either artificial polymeric or biological scaffolds, which may derive from human tissue donation or animals [24]. Total artificial tissue-engineered heart valve concepts would solve many unmet clinical demands such as permanent availability of different sizes and lengths. Total artificial concepts have shown good results in the technical implementation of valved polymeric conduit production and have successfully been used for in vitro and in vivo seeding of different (stem

1 Introduction Tissue engineering became a growing field of research over the past years. The older the humans get the higher is the need for replacement of damaged tissue. It is not possible to cover the demand by donated tissue or organs with transplantation [ 1 ]. This leads to the idea of growing artificial tissue, e.g. heart valves or bone tissue, in vitro and implant them into the patient [ 2 ]. Therefore a scaffold is necessary to mimicry the extra cellular matrix (ECM) and support the cells during growth [ 1 ]. Electrospinning is a very suitable method

Current Directions in Biomedical Engineering 2017; 3(2): 631–634 Sylvia Pfensig*, Sebastian Kaule, Michael Sämann, Michael Stiehm, Niels Grabow, Klaus- Peter Schmitz and Stefan Siewert Assessment of heart valve performance by finite-element design studies of polymeric leaflet-structures Abstract: For the treatment of severe symptomatic aortic valve stenosis, minimally invasive heart valve prostheses are increasingly used, especially for elderly patients. The current generation of devices is based on xenogenic leaflet material, involving limitations with

Current Directions in Biomedical Engineering 2019;5(1):493-496 Open Access. © 2019 Carsten Tautorat et al., published by De Gruyter. This work is licensed under the Creative Commons Attribution 4.0 License. Carsten Tautorat, Sebastian Kaule, Jörg Kaminsky, Klaus-Peter Schmitz, Niels Grabow and Wolfram Schmidt* Pressure sensor emulator to improve long- term stability of heart valve testing systems Abstract: Fluid mechanical characterization of artificial heart valve prostheses requires reliable measurement of temperature, flow and pressure at normal

Stefan Oschatz*, Stefanie Kohse, Volkmar Senz, Thomas Eickner, Klaus-Peter Schmitz and Niels Grabow Accelerated in vitro-calcification of potential urethane based heart valve replacement materials group of Glasmacher extensively investigated the calcification of commercially available artificial heart valves consisting of pericardial tissue under pulsatile stress over a period of 6 weeks at 37°C, approaching in vivo-conditions with respect of a dependence that calcification considerably depends on material stress in valve opening-closing processes [3

Sylvia Pfensig*, Sebastian Kaule, Robert Ott, Carolin Wüstenhagen, Michael Stiehm, Jonas Keiler, Andreas Wree, Niels Grabow, Klaus-Peter Schmitz and Stefan Siewert Numerical simulation of a transcatheter aortic heart valve under application-related loading Abstract: For the treatment of severe symptomatic aortic valve stenosis, minimally invasive heart valve prostheses have more recently become the lifesaving solution for elderly patients with high operational risk and thus, are often im- planted in patients with challenging aortic root configuration. A

Finja Borowski*, Michael Sämann, Sylvia Pfensig, Carolin Wüstenhagen, Robert Ott, Sebastian Kaule, Stefan Siewert, Niels Grabow, Klaus-Peter Schmitz and Michael Stiehm Fluid-structure interaction of heart valve dynamics in comparison to finite-element analysis Abstract: An established therapy for aortic valve stenosis and insufficiency is the transcatheter aortic valve replace- ment. By means of numerical simulation the valve dynamics can be investigated to improve the valve prostheses perfor- mance. This study examines the influence of the hemody- namic