Dear Ashley,
Thanks very much for your inquiry. While we would be very interested in your personal experiences in your essay, we also need to make sure the essay requirements are standardized. You would need to write about how an invention relates to one of the 5 topics listed. If you can find out more about the pacemaker you use you may find that it is based upon a design that is also used in heart patients or it may be related in another way. I hope that helps.