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Headphones used with MP3 digital music players like the iPod may interfere with heart pacemakers(起搏器) and implantable defibrillators(除颤器), U. S. researchers said.
The MP3 players themselves posed no threat to pacemakers and defibrillators, used to normalize heart rhythm. But strong little magnets inside the headphones can confuse the devices if placed within 1. 2 inches of them, the researchers told an American Heart Association meeting in New Orleans.
Dr. William Maisel of the Medical Device Safety Institute in Boston led a team that tested eight models of MP3 player headphones in 60 defibrillator and pacemaker patients.
They placed the headphones on the patients’ chests, directly over the devices. The headphones interfered with the heart devices in about a quarter of the patients--14 of the 60--and interference was twice as likely in those with a defibrillator than with a pacemaker.
Another study presented at the meeting showed that cell ph
A. MP3 players can interfere with heart, pacemakers and defibrillators.
B. The magnets inside the headphones can interfere with pacemakers and defibrillators.
C. The loud music beats pose a threat to pacemakers and defibrillators.
D. MP3 players are placed too close to pacemakers and defibrillators.