UK ICD-user here. So three weeks ago I had a severe ventricular fibrillation episode - I fell unconscious, had bystander defibrillation, air ambulance to hospital and two days later had an ICD fitted just below my left collar bone and was out of hospital the next day.

I use an iPhone 12Pro. The advice I was given was don't hold any phone closer than six inches away from the device- so holding it to my right ear is fine. Mag fields right next to the device can stop it sensing or in rare circumstances can cause a factory reset.

The biggest EM hazards in my house are the induction hobs on my cooker - these are worse than the phone. On full power I have to keep at least 60cm away from them or they will blind / alarm the ICD. So I am more concerned about them than the phone.

[Edit] Other hazards are drills held close to my chest and even the capes used by hair-dressers that have magnetic clasps to stay shut. Standing right next to the speakers at a concert is also not-advised.

It's a PSA: if you have an implanted defibrillator, don't keep iPhone 12 in a shirt pocket. No need for any more drama than that. Reminds me of antennagate, to which Jobs responded: "Don't hold it that way."

For what it’s worth, the FDA published a similar warning[1] earlier this year. I’m a little surprised the proliferation of random accessories (phone cases, headphones, etc) with strong-ish neodymium magnets over the last few years hadn’t already raised an alarm.

1. https://www.fda.gov/radiation-emitting-products/cell-phones/...

The problem appears to me to be a design problem of the implanted devices, not the iPhone.

Unless I'm mistaken this is what's happening:

1. ICDs want/need to communicate with the outside (at least one way).

2.However, this is not trivial since a human body is a bag of salt water. Therefore low frequencies are needed.

3. Low frequencies are very difficult at the necessary length scales with electric fields, so they used the magnetic field instead.

So far, so good. But then they assumed that the person would never be next to a magnet? That's a design flaw on their end, not the iPhone's. There's magnets, and low moving large currents, everywhere!

The should have implemented a primitive type of port knocking.

I don't know the entire story, but my wife is a cardiac ICU nurse and says magnets are part of the normal procedures for dealing with ICDs. They'll slap a magnet on the chest of an ICD patient to inhibit the device if it malfunctions.

All I'm saying from that is while a lot of comments around here are calling it design flaws, I'm pretty sure to a certain extent its a design decision. If you have a patient on the stretcher and you need to disable that thing now then a magnet seems like a perfectly reasonable & safe thing to use. Requiring specialized devices that might not be available at all times seems like the design flaw. Asking patients with specific health needs to avoid certain activities/devices is not a huge stretch.

ICD patient and avid cell phone user here. They tell us magnets will disable the device. This is by design, they include a hall effect sensor to allow medical personnel to disable the devices. They aren't exactly specific about how big a magnet and how close it has to be.

My device sends data to a base station which reports back and is also interrogated every 6 months by a electrophysiologist and they can see if and when it has been disabled.

Mine has been disabled twice so far, once by using the Boston Scientific interrogation device to turn it off, and once by a surgeon taping a magnet to my chest!

Great opportunity for a killer app.

Question for phone repair folks: On teardown photos, it seems like the iPhone magnets are accessible after dealing with a few layers of adhesive. Is it possible and if so, how difficult is it to remove the ring of magnets?

I guess those $10 magnetically attached name tags are bad too then.

This might create a niche market for mu metal iPhone cases.

In addition to heart implants, cochlear implants are an issue too. Not only that but the electronics for controlling the implant require an iPhone app.

The heart itself is kind of an electromagnetic device - are there any studies on the health implications in healthy people of having powerful magnets placed next to it?

Place phone in pants pocket not shirt pocket. I wonder if this is a new phenomena with wireless charging or if other phones could have caused problems and were never tested.