Although the intention of most in vitro accelerated tests performed on implantable
medical devices is to exacerbate particular failure modes and evaluate the reliability of a
device rapidly, these tests often do not yield the same type of failures, if any failures
occur at all, as observed in service (i.e., in vivo). Unfortunately, a definitive correlation
between in vitro accelerated life testing and in vivo experience can occur only after a
device has been implanted in a human. Therefore, developing an appropriate suite of
accelerated tests to estimate the service life of active implantable medical devices in
vivo requires careful evaluation of the mechanical, environmental, and electrical
conditions under which the devices typically operate. In this presentation, we discuss
some of the considerations that must be taken into account, including the use of “abuse”
tests intended to identify potential in vivo failure modes before accelerated tests are
designed.