Engineering researchers at the University of Michigan designed a device that harvests energy from the reverberation of heartbeats through the chest and converts it to electricity to run a pacemaker or an implanted defibrillator. These mini-medical machines send electrical signals to the heart to keep it beating in a healthy rhythm. By taking the place of the batteries that power them today, the new energy harvester could save patients from repeated surgeries.

The new device could generate 10 microwatts of power, which is about eight times the amount a pacemaker needs to operate. It generates more energy than the pacemaker requires, and it performs at heart rates from 7 to 700 beats per minute.

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Also: A thermoplastic material can be used in device components such as guide wires or pacemaker leads.