Calling Death’s Bluff
Implantable defibrillators can save thousands of lives—but which ones?
By Ben Harder
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.
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However, doctors do have an earlier chance to intervene. By implanting a specialized device into a person’s chest, they can equip the heart to recover instantly when death comes knocking. When the electrical leads of these so-called implantable cardioverter-defibrillators, or ICDs, detect an abnormal heart rhythm, the attached pager-size generator delivers a shock that restores the normal cadence.