Magnets in the Apple iPhone 12 can disable defibrillators, Henry Ford doctors found.
The new iPhone contains stronger magnets associated with charging and other accessories, which prompted Henry Ford Heart & Vascular Institute physicians to test whether they may interfere with implantable cardiac devices.
When Dr. Gurjit Singh, a Henry Ford cardiologist, brought the iPhone close to a patient's chest that had a Medtronic defibrillator, the device was deactivated, he said. It started working again when they took the phone away.
"We were all stunned," Singh said in prepared remarks. "We had assumed that the magnet would be too weak in a phone to trip the defibrillator's magnetic switch. "
More than 400,000 Americans receive defibrillators and pacemakers every year, according to a 2011 study. Defibrillators detect an irregular heartbeat and shock the heart back into a normal rhythm, and pacemakers use electricity to keep the heart beating.
Strong magnets can be used to turn defibrillators off; they can also cause pacemakers to deliver potentially fatal electrical impulses that cause the heart to beat out of sync.
Singh and his colleagues published a letter to the editor Jan. 4 in the HeartRhythm medical journal, which got the attention of the Food and Drug Administration, the Association for the Advancement of Medical Instrumentation as well as Apple, according to Henry Ford. The FDA, which Henry Ford officials said is conducting its own tests, did not appear to have any safety alerts on its website as of publication.
"If significant new information becomes available, we will inform patients and healthcare providers," the administration said in a statement, directing people to its website.
Apple updated a warning on its website on Jan. 23 instructing iPhone 12 users to "keep your iPhone and MagSafe accessories a safe distance away from your device (more than 6 inches / 15 cm apart or more than 12 inches / 30 cm apart if wirelessly charging). But consult with your physician and your device manufacturer for specific guidelines." Henry Ford doctors and the FDA echoed that advice.
Apple, in a statement, highlighted part of the post that read: "Though all iPhone 12 models contain more magnets than prior iPhone models, they're not expected to pose a greater risk of magnetic interference to medical devices than prior iPhone models."
"We believe our findings have profound implications on a large scale for the people who live daily with these devices, who without thinking, will place their phone in their shirt pocket or upper pocket or their coat – not knowing that it can cause their defibrillator or pacemaker to function in a way that could potentially be lethal," Singh said.
Henry Ford physicians are preparing a more comprehensive study of all major brands of defibrillators and pacemakers to determine if they are also affected by the strong magnets in the iPhone 12 and other portable devices.