If a heart beats too slowly, the pacemaker will use electrical signals to help set a normal rate.

VOA: special.2010.06.02

Here is as pacemaker and this pacemaker does the same thing that a heart pacemaker does, it generates periodic electrical signals.

它和心脏起搏器发挥的作用相似,发出周期性的电信号

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This is similar system to that used by some heart pacemaker systems, but these only report back technical information about the condition of the implant, rather than gather extensive data about the condition of the patient.

BBC: Telephone heart sensor under test

After undergoing another surgery to replace Medtronic leads--wires connecting the pacemaker to the heart--with ones from Guidant, Davis sued both the hospital system and Haugland, charging medical malpractice and complaining that the second surgery could have been prevented.

FORBES: Unintended Consequences

Their team showed that the device could generate 18 times the amount of energy needed to power a pacemaker using a normal heart beat, according to Dr. Karami.

WSJ: Harnessing Energy From the Body to Power Devices