Constructing an artificial heart requires materials such as metals, ceramics, plastics, and polymers that are lightweight and durable. At the same time, these materials must be biologically inert. They must work synergistically with other body systems and not trigger attacks by the body’s natural system of immune defenses that would lead to the disruption of the circulatory system and, ultimately, death. An artificial heart also requires sufficiently smooth surfaces so as not to disrupt blood flow through the heart or damage fragile blood cells. A TAH needs a power source that can maintain an efficient and steady stream of energy for long periods of time while being small enough to fit completely inside the body. Both the pump and the power source must be capable of responding to changes in position, temperature, and pressure associated with the needs of the person using the machine. The decision to launch a program to build a totally implantable heart had its roots in a series of exploratory meetings held during the 1950s at the NIH (Shaw). Enthusiasm for undertaking the research accelerated in the 1960s as physicians and engineers began to build and successfully use the first heart-lung machines, external pumps that could be used to support blood circulation in the body. After a few hours, these machines damaged the blood cells (Zareba). Still, the heart-lung machine was a crude, partial artificial