Headphones Can Interfere with Pacemakers: Study

It should be common sense that electronic devices can cause interference with other electronic devices (remember the old pacemaker / microwave problem?). After all, an earlier study about RFID tags interfering with medical devices has been released, and a new study released on Sunday shows that headphones might throw off pacemakers and implantable cardioverter defibrillators (ICDs) when placed within an inch of the medical devices.

The presentation, titled Electromagnetic Interference (EMI) of Implanted Cardiac Devices by MP3 Player Headphones was shown at the American Heart Association's annual scientific sessions in New Orleans on Sunday. It took a look at the possible interaction between the magnets in headphones and implanted devices. The study compared eight different headphones on 60 patients. When the headphones were about an inch from the device, interference was detected in four of the 27 pacemaker patients and 10 of the 33 with defibrillators. A pacemaker reset itself in one patient. The study's leader, Dr. William Maisel, a cardiologist at Beth Israel Deaconess Medical Center in Boston and a heart device consultant to the Food and Drug Administration said:
"Headphones contain magnets, and some of these magnets are powerful. The headphone interaction applies whether or not the headphones are plugged in to the music player and whether or not the music player is on or off."
However, he cautioned that people should not overreact to the news, but he added it would be a good idea to keep small electronics at least a few inches from implanted medical devices. Nearly 2 million people worldwide have pacemakers, defibrillators or other devices to help regulate their heartbeats. Results of the study, including the models tested, are below:

MP3 Player Headphone Clinical Interactions with PM-ICD
Model/ TypeMagnetic Field Strength (gauss)*Clinical Interactions
PM (n=27)ICD (n=33)Total (n=60)
MDR-Q22LP (clip-on)204 (15%)10 (30%)14 (23%)
SBC HS430 (clip-on)102 (7%)1 (3%)3 (5%)
SHE5920 (in ear)4000
In ear4000
MDR-E828LP (in ear)3000
HA-F130-A (in ear)201 (3%)1 (2%)
In ear2000
HA-FX33-A (in ear)0000

4 (15%)10 (30%)14 (23%)
* At 2 cm from Gaussmeter