Invention: Heart-Powered Pacemaker

Implanted pacemakers and defibrillators have to be replaced when their power sources run low — normally every 7 to 10 years. The surgery requires general anaesthetic and carries some risk for patients. But David Tran and colleagues at Stanford University, California, U.S., say it may be possible for the devices to harvest their own power from the human body.
NewScientistTech