Those who received normal scores on the test had "a very good prognosis and are likely to benefit little" from having defibrillators implanted, the study authors wrote.
It may seem to make sense to simply install defibrillators in anyone who's at a higher-than-normal risk of cardiac death. The machines, after all, are designed to keep people alive by shocking the heart into a normal rhythm when it is in danger of not beating due to an electrical disruption.
But by one estimate, 17 defibrillators need to be implanted in order for one to save a single life. And, according to Chan, it can cost $40,000 to implant one of the little machines.
In addition, defibrillators don't make patients feel better on a day-to-day basis, Chan said. "It doesn't make your symptoms any better or make you walk longer or climb a stairs without being short of breath. The only thing it prevents is sudden death from cardiac arrhythmia."
For more on sudden cardiac death, visit the American Heart Association.
SOURCES: Paul Chan, M.D., cardiologist, Mid-America Heart Institute, Kansas City; Nov. 6, 2007, Journal of American College of Cardiology
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