Keep your headphones away from pacemaker

New Orleans: Have a pacemaker or an implanted defibrillator? Don't keep your iPod earbuds in your shirt pocket or draped around your neck - even when they're disconnected.

A study finds that some headphones can interfere with heart devices if held very close to them.

They might even prevent a defibrillator from delivering a lifesaving shock, say doctors who tested them.

"Headphones contain magnets, and some of these magnets are powerful," said the study's leader, Dr William Maisel, a cardiologist at Beth Israel Deaconess Medical Centre in Boston.

"I certainly don't think people should overreact to this information, but it's smart to keep small electronics at least a few inches from implanted medical devices, and not let someone wearing headphones lean against your chest if you have one."