The automated external defibrillator is a portable, self-contained machine that can shock the heart back into rhythm.

CNN: Cardiac-arrest victims' parents push for school defibrillators

Two lives that could have been saved, their parents said, with one solution: an automated external defibrillator.

CNN: Cardiac-arrest victims' parents push for school defibrillators

For the next several years, Vollmer worked out and competed with an external defibrillator at poolside in case the worst happened.

FORBES: Dana Vollmer: The Definition of What it Really Means to be a Champion

Learn CPR and get training on an automated external defibrillator, or AED.

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