Download Project Report by Yiğit Yorulmaz (Word Document)

Heart Turcica Centrifugal – Development of the First Miniature &
Implantable LVAD Heart Pump System in Turkey
Yiğit Yorulmaz, Robert College
Associate Prof. İsmail Lazoğlu, Koç University
Abstract:
I’ve spent a total of six weeks in Koç University Summer Research Program. I have
concentrated on many different aspects of the project I was assigned. Each time, I developed my
knowledge on various branches of engineering and biology. I researched on left ventricular assist
devices in general, and then narrowed my research to the specific LVAD Heart Turcica. Next, I
learned more about biocompatibility, immunobiology and ISO 10993. As the project was heavily
involved in mechanical engineering, it was deemed necessary that I learn SolidWorks, a
computer-aided design software. With that skill, I spent one week modeling an object using
SolidWorks. Each of these concentration areas helped me not only develop myself academically,
but also experience what it is to be a research fellow.
Article:
In this Koç University summer research program, development of the left ventricular
assist device (LVAD), Heart Turcica, has been my area of focus. In the course of the six weeks I
have spent in this research program, I concentrated on various aspects of the project.
Consequently, I gained insights on many branches on engineering including mechanical and
biomedical engineering.
When I joined the research team, the pump had already been designed. Therefore, it was
paramount that I quickly learn how left ventricular assist devices basically work and what they are
used for. In my first week, I researched on many types of LVADs and their development over
time. I read articles on congestive heart failure (CHF) and how LVADs promise a solution. After
getting a basic notion on heart pump systems, it was time to research on the specific project I
was a part of. I started by reading Emre Bıyıklı’s master’s thesis on the project describing the
details of the Heart Turcica design process. In the Suna Kıraç Library on campus, I found and
read Gökhan Yıldız’s master’s thesis on the project in order to further develop my understanding
of the Heart Turcica project. Both of these master’s theses described how 1-D design tools,
Computational Fluid Dynamics (CFD) and trial and error methods could be used in the design
process of a left ventricular assist device. Meanwhile, I researched on the importance of hydraulic
efficiency and distribution of shear stress in the device.
In the Heart Turcica project, many engineering braches are integrated. Even though the
design of the pump system heavily depends on mechanical engineering, one must not forget that
the device will be implanted to humans. As a consequence, biomedical engineering plays an
important role in the design process of the device. In the second and third weeks the program, I
researched on the biocompatibility qualities of the biomaterials used in the device. I started by
learning more about titanium and its properties that makes it highly biocompatible. Later, I
focused on methods of titanium coating including plasma spray coating. With the guidance of
Çağdaş Dinçer, I learned more about coating biomaterials with the anticoagulants heparin and
warfarin. After researching further on the immunobiology of left ventricular assist devices, I
watched a complete LVAD implantation surgery in order to gain insight on the medical aspect of
the project. Next, I researched on ISO 10993 so that I can better understand how
biocompatibility is achieved and tested in vitro.
My research on biocompatibility led me to a comparison of many types of LVADs. In
previous weeks, I had already learned that there were three generations of left ventricular assist
devices. First generation LVADs were pulsatile and had mechanical bearing. Second generation
had a continuous-flow design with mechanical bearings while the third generation had magnetic
or hydraulic levitation. As many research teams in the world currently focus on the development
of the third generation LVADs, I prepared a report comparing them for Deniz Erbulut, a postdoctoral research fellow. Following that, Deniz Erbulut asked me to write another report on
various parts of LVADs and their function. These two reports helped me better understand the
current state of the art and future areas of improvement.
Considering the fact that the project depends heavily on engineering skills, with the
guidance of İsmail Lazoğlu, I decided to learn a computer-aided design (CAD) software:
SolidWorks 2009. I started by reading an eBook that serves as a manual for the software. Then, I
watched educational movies both in Turkish and in English, in order to increase my
understanding of the software before I started to use it. In a short period of time, I learned skills
in SolidWorks such as sketching, extruded cut, extruded boss, filleting, 2D technical drawing and
annotations. After, getting used to the ways of designing three dimensional solids in SolidWorks,
İsmail Lazoğlu asked me to model an object used to cool lasers. The work took approximately
one week. The experience and information I gather in that week is immeasurable and invaluable
because software such as SolidWorks enables an engineer to take a big step forward in 3D design.
I am most grateful that I have been given this opportunity to develop myself and
experience what it is to be a research fellow. I strongly believe that this experience will aid me in
the near future. In addition, I will be more confident when I decide what career I will pursue. For
that, I thank İsmail Lazoğlu, Deniz Erbulut and Koç University.