Pacemakers are crucial electronic devices that help keep people with an erratic heart operation alive. They are small implants that stimulate the heart muscle to beat according to a fixed rhythm, and have been saving lives since 1958.
However, all pacemakers have the same problem—they require batteries to operate. Of course, batteries eventually run flat, and in the early days of pacemakers, the batteries would need to be replaced fairly often, requiring surgery each time.
In the late 1970's, scientists at the Los Alamos Scientific Laboratory started research into the production of a nuclear powered pacemaker. The first implant was done in 1970 and a total of 132 patients received similar devices over the following 13 years. The pacemakers were powered by a plutonium fueled "battery" and were expected to last in excess of 80 years.
As of 2007, nine nuclear recipients were still alive, but in all cases the pacemakers had outlived their hosts.
The advent of lithium batteries and the increased efficiencies of modern electronics eventually led to the demise of the nuclear pacemaker.