In a study reported at the American Heart Association’s Scientific Sessions 2008 held in New Orleans, LA., researchers from the Medical Device Safety Institute at Beth Israel Deaconess Medical Center (BIDMC) in Boston, MA investigated the effects of MP3 player headphones, most of which contain the magnetic substance neodymium, on the operation of implanted cardiac devices. The research team tested eight different models of MP3 player headphones (including both the clip-on and ear-bud variety) with iPods® on 60 defibrillator and pacemaker patients. Findings indicated a detectable interference with the device in 14 (23 percent) patients. Implanted cardiac devices (ICDs) send either low- or high-energy signals to the heart; however, ICDs near magnets may temporarily stop detecting abnormal heart rhythms and can temporarily deactivate the defibrillator. Specifically, field strength of 10 Gauss at the site of the pacemaker and defibrillator has the potential to interact with an implantable device. Still no reaction to the device was noted if the headphones were at least 3 centimeters from the skin surface, and in most cases removing the headphones restored normal ICD functioning. According to senior author Dr. William H. Maisel, patients should not drape headphones around their necks or carry them in chest pockets.Read more at the BIDMC website.
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