Biomedical Engineering Reference
In-Depth Information
8
Biomaterials for improving the blood and tissue
compatibility of total artificial hearts (TAH) and
ventricular assist devices (VAD)
D.UFUKERBULUT and I.LAZOGLU,
Koc University, Turkey
Abstract: This chapter reviews biomaterials used for artificial hearts and
ventricular assist devices. The chapter identifies some of the commercially
available cardiac devices and the materials used within, stretching the most
important polymers, metals and ceramics. It then discusses the interaction
between blood/tissue and biomaterials and subsequently the way of
refinement of biomaterials in order to achieve optimum performance. The
chapter includes also the evaluation of biomaterials in terms of their blood
and tissue compatibility and related international standards.
Key words: biomaterials, cardiac devices, biocompatibility, LVAD, total
artificial heart.
8.1
Introduction
What are the initial requirements for biomaterials of cardiovascular assist
devices? The first problem that researchers had to face during early development
was to find an appropriate material that can offer both drive and flexion
capabilities as well as compatibility with the human body. Perhaps the most
scientific problem was to overcome the issue related to the interaction between
biomaterial surface and human body. In addition, biomaterial must not produce
blood clots (thrombi), which cause strokes. To overcome the above problems,
materials have to be specifically considered for medical devices and their
components for use within the human body.
In this chapter, early attempts and recent advances in the field of biomaterials
of artificial hearts are demonstrated, in particular the interaction of the heart
with blood and tissue. Section 8.2 reviews the chronological background of
ventricular assist devices and total artificial heart evolution. Section 8.3 estab-
lishes an appropriate background indicating critical biocompatible (polymers,
metals, ceramics, etc.) in a specified device, including explanation of utilization
of each materials and why the different materials are used for the same
application. Section 8.4 outlines the mechanical and physical requirements of
