MagSafe has 'clinically significant' risk to cardiac devices, says American Heart Association

Apple MagSafe devices can interfere with pacemakers when placed directly over the skin, or in very close proximity, says the American Heart Association.

The Journal of the American Heart Association has concurred with a previous report by the Heart Rhythm Journal which said close contact with an iPhone 12 affected certain implantable cardiac devices. As with that report, the American Heart Association says the effect are solely when the iPhone is on or very near the implant.

For its tests, the American Heart Association chiefly used an iPhone 12 Pro Max. However, the report notes that "[s]elect devices from all three major device companies were found to have magnetic susceptibility."

"Our study demonstrates that magnet reversion mode may be triggered when the iPhone 12 Pro Max is placed directly on the skin over an implantable cardiac device and thus has the potential to inhibit lifesaving therapies," say the report writers in the Journal of the American Heart Association.

The testing involved placing the iPhone 12 Pro Max in very close proximity to a series of 11 different pacemakers and defibrillators.

Some were devices already implanted in a series of patients, which the report calls "in vivo" testing. Others were "ex vivo," or newly unboxed devices not yet implanted.

The degree of interference did vary across the testing, but all devices were affected. The report says that "the iPhone 12 Pro Max was able to trigger magnetic reversion mode at a distance up to 1.5cm [0.6 inches]."

"Apple Inc, has an advisory stating that the newer generation iPhone 12 does not pose a greater risk for magnet interference when compared to the older generation iPhones," notes the report. "However, our study suggests otherwise as magnet response was demonstrated in 3/3 cases in vivo."

"In comparison to the older generation iPhone 6, a study performed by Lacour et al, found no cases of magnet response in a sample size of 148 patients," it says.

"Our case series has several clinical implications," continues the report. "People often put their smartphones in a breast pocket over a device which can be in close proximity to CIEDs [cardiac implantable electronic devices. This can lead to asynchronous pacing or disabling of antitachycardic therapies."

The report recommends a wider study, but also that heart patients who use any smartphones should "consult with a heart rhythm specialist" for advice.

In January 2021, Apple updated its MagSafe support document to recommend that users keep the iPhone 12 six inches away from any medical implants.

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15 Comments

dewme 5738 comments · 10 Years

About 3 years ago

The FDA has issued a statement about this https://www.fda.gov/radiation-emitting-products/cell-phones/magnets-cell-phones-and-smart-watches-may-affect-pacemakers-and-other-implanted-medical-devices . It seems like the American Heart Association should be working with the FDA to formulate guidance and parameters for product makers to follow. It may be time for product makers to be required to include a warning label or insert with their product packaging to allow consumers to be more aware of the potential risks.

lkrupp 10521 comments · 19 Years

The class action lawyers are drooling over their morning coffee.

MplsP 4022 comments · 8 Years

lkrupp said:

The class action lawyers are drooling over their morning coffee.

Probably, but this is no different from any other magnet.

The other point to note that the article hinted at but didn’t explicitly state is that with rare exceptions, a magnet doesn’t turn off a pacemaker, it causes it to revert to a default backup mode. This mode is intentionally used routinely in surgery where electrocautery can cause interference.

With defibrillators a magnet will turn off the defibrillator function which can be a big deal, but only if the patient happens to need it while the magnet is on. Defibrillators are not primary therapies; they’re emergency backups. It’s not good to have a phone in your pocket turn off your defibrillator, but the likelihood of something bad happening is fairly low.

In both cases, the device emits a tone, warning that it has sensed the magnet.

I’m sure someone will probably sue, but they’d have to show harm which would be difficult. I do think Apple needs to post a warning, though. If for no other reason than to cover their posteriors.

Edit: one key difference with an iphone is that you are more likely to put it in your shirt pocket, potentially placing it in close proximity to an implanted device. I agree with Dewme and cognomen42 - the AHA should work with Apple and other phone manufacturers on this.

rob53 3307 comments · 13 Years

MplsP said:

lkrupp said:

The class action lawyers are drooling over their morning coffee.

...
Edit: one key difference with an iphone is that you are more likely to put it in your shirt pocket, potentially placing it in close proximity to an implanted device. I agree with Dewme and cognomen42 - the AHA should work with Apple and other phone manufacturers on this.

I see your comment only being applicable to men, women's clothes generally do not have a shirt pocket. Men might put their phone in their coat pocket. which might be too close but people with pacemakers/defibrillators are instructed on what can and what can't be placed anywhere near the heart by their doctors. As for me, I can think of only one time where I put my phone in a shirt pocket. To me this is the worst place to put a $1K device, easy to fall out and easier to be pinched.

mknelson 1147 comments · 9 Years

"For its tests, the American Heart Association chiefly used an iPhone 12 Pro Max. However, the report notes that "[select devices from all three major device companies were found to have magnetic susceptibility.""

This sentence is confusingly worded. "Chiefly used", followed by "However" and "select devices" could be read as other brands of phone. This study appears to have only used iPhone 12 Pro Max. iPhone 6 was in a previous study. The major device companies are the cardiac implant manufacturers.

The full paragraph from the article is "Our study demonstrates that magnet reversion mode may be triggered when the iPhone 12 Pro Max is placed directly on the skin over an implantable cardiac device and thus has the potential to inhibit lifesaving therapies. Select devices from all three major device companies were found to have magnetic susceptibility."