Implantable defibrillators can save thousands of lives—but which ones?
Some hearts seem to be beating normally one moment, but then quiver for an instant and fall still forever. In these cases, the heart's electrical circuitry goes haywire, and its contractions accelerate until the organ flails uselessly and shuts down. Sudden cardiac death awaits nearly half a million people nationwide in the next 12 months. Once a person's heart stops, there is usually little that any hospital can do.