[HN Gopher] Phones containing magnets inhibit implantable cardio...
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Phones containing magnets inhibit implantable cardioverter
defibrillators
Author : Tomte
Score : 88 points
Date : 2021-08-23 11:21 UTC (11 hours ago)
(HTM) web link (bhrs.com)
(TXT) w3m dump (bhrs.com)
| gorkish wrote:
| 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?
| mensetmanusman wrote:
| This might create a niche market for mu metal iPhone cases.
| amrcnimgrnt wrote:
| 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.
| bdcravens wrote:
| The entire medical devices industry tackles this issue just
| fine (for example, I have a percussion vest for respiratory
| therapy that uses strong magnets, and there's no shortage of
| warnings).
| KineticLensman wrote:
| > Unless I'm mistaken this is what's happening:
|
| The actual problem is that EM fields blind the device so that
| they can't sense the cardiac arrhythmias they are designed to
| fix, this rendering them useless.
|
| > ICDs want/need to communicate with the outside (at least one
| way).
|
| My St Jude Ellipse ICD communicates bidirectionally (control
| inputs in, telemetry out).
| amrcnimgrnt wrote:
| I'll leave it to you, a user, that strong EM fields also
| blind the devices. The signals the ICD is trying to measure
| are very weak. I can imagine that strong 50/60Hz surge
| currents really screw things up, especially in single
| conductor power distribution situations (UK ring circuits,
| rural farms, etc).
|
| That being said, the article (TL/DR) appears to focus on
| "static" magnetic fields. The near field charging feature of
| the iPhone barely makes mention.
|
| I think the "disable ICD" being a simple magnetized reed
| switch for an implantable medical device is a bit silly. At
| least tap a code into that reed switch a little!
| argvargc wrote:
| 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?
| joezydeco wrote:
| Decades of MRI research and clinical use have probably proven
| this to be safe.
| argvargc wrote:
| Where are the boundaries though? Are they established?
|
| There must be a point at which a magnet of power n causes a
| negative effect that increases along with n, time, and
| exponentially with proximity?
| shadowgovt wrote:
| As far as we can tell... Yes, such a magnet exists. But it
| costs the power of a small city to maintain its field, and
| the patient would experience all kinds of strange effects,
| including levitating in it as it induced magnetic forces
| across their water molecules...
|
| (Seriously though, there are research magnets powerful
| enough to levitate plastic that people have jammed their
| hands into with no ill effects. It seems that across a wide
| range of intensities at least, the human body just does not
| care. This is, perhaps, surprising given how much
| electrochemical activity is necessary for continued
| homeostasis, but it appears to be observationally true).
| argvargc wrote:
| Wow, thank you.
|
| In a brief search, I found this strange and interesting
| article from 1983, regarding experiments conducted at
| Lawrence Berkeley Laboratory of the University of
| California:
|
| https://www.nytimes.com/1983/02/22/science/do-enormous-
| magne...
|
| TL;DR - there were detectable effects on heart function,
| eye function and possibly sense of direction. The effects
| were deemed safe at the levels studied.
|
| Here is the study the article appears to be about (on
| page 86, as numbered in the scan):
|
| https://inis.iaea.org/collection/NCLCollectionStore/_Publ
| ic/...
|
| Going by its closing remarks, it appears this was an
| active field of research at the time.
| lvncelot wrote:
| There actually have been experiments with levitating
| animals[1] via a very strong magnetic field - they've
| been fine afterwards.
|
| [1]
| https://www.ru.nl/hfml/research/levitation/diamagnetic-
| levit...
| argvargc wrote:
| Well worth the click, the article (1997) starts with a
| great explainer, and has photos.
|
| Deserves its own post.
| tgv wrote:
| I know of an 11T MRI (in Paris, IIRC) which knocks people
| unconscious when they move too fast. Apparently, the
| field across your skull inhibits (some) spike
| propagation. Doesn't require that much power.
| xondono wrote:
| It's not unique to MRIs, but it's one of the niche
| applications where this happens.
|
| Working in certain environments (IIRC >2T) requires
| special training, that include things like "slow
| walking", since moving too fast would induce currents in
| the brain that could knock you out.
|
| For a product that I worked in we had to find a cheap way
| to create a 2T static field for validation, the
| complications of each of the possibilities were amazing.
| nabla9 wrote:
| No effects has been found. It's considered pseudoscience.
|
| https://en.wikipedia.org/wiki/Magnet_therapy
| KineticLensman wrote:
| 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.
| philjohn wrote:
| Hope you're doing better now after the ICD! My 81 year old
| father had one fitted a few months ago and it's been pretty
| much life changing (once he was allowed out of the hospital,
| they managed to nick his lung, which was a whole big thing).
|
| Was going to say induction hobs - that's a huge one, especially
| as gas is eventually phased out and they become the defacto hob
| type.
|
| NHS recommendation[1] is, as you said, 6 inches for most mobile
| phones, but no special callout for the 12.
|
| Apple goes further[2] and says 12 inches when wirelessly
| charging, which also makes sense.
|
| [1] https://www.nhs.uk/conditions/pacemaker-
| implantation/recover... [2] https://support.apple.com/en-
| gb/HT211900
| KineticLensman wrote:
| > Hope you're doing better now after the ICD!
|
| Thank you! I'm just 60 and was (I believed) in good health.
| My VF episode was a glitch in my heart's conduction cycle,
| and the various tests I received show that my heart is
| physically healthy. So I feel 'perfectly okay' apart the
| almost dying thing. My biggest health issue now is the
| cracked risks from the superbly enthusiastic CPR I received,
| but the pain from coughing and moving awkwardly is a small
| price to pay.
| stevespang wrote:
| Lawyers will be upset you published this - - now they cannot make
| money sueing a REALLY deep pocket.
| culturestate wrote:
| 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/...
| oneplane wrote:
| Especially since magnets are used so widely in so many products
| you'd think that even some sort of
| test/certification/measurement that would happen anyway (RFI?)
| would also note that there is a strong field present. This
| stuff gets measured all the time, also for equipment that is to
| be used in aerospace and hospitals... the whole concept of
| devices interfering with each other isn't new. But apparently
| it's still overlooked when it's about consumer electronics as
| if those couldn't possible interfere/cause interference.
| xondono wrote:
| > This stuff gets measured all the time, also for equipment
| that is to be used in aerospace and hospitals...
|
| They only measure _dynamic_ magnetic fields (i.e.
| electromagnetic fields). There are essentially no regulatory
| limits in static fields, since they don 't really interfere
| with RF signals.
|
| In fact, is amazingly easy to purchase neodymium magnets of a
| size _that should not be_ that easily available, which
| explains the hilarious safety videos like this one[1]
|
| [1] https://www.youtube.com/watch?v=0t8yDnyOaQ8
| oneplane wrote:
| Now that I read that, it seems obvious that static fields
| and RF wouldn't interact like that... Thanks!
|
| The video is very well done (for a semi-pro it seems?),
| it's one of those things where people (including me) might
| think "oh yeah magnets, I know about those" but you
| actually don't, or at last not at the scale that you might
| need.
|
| That reminds me of this LPL video about Gallium:
| https://www.youtube.com/watch?v=jeghGhVdt9s where you might
| think: oh yeah, metals, those are sturdy blocks that you
| need to weld or saw.
| jaywalk wrote:
| In this case, the magnet isn't really _interfering_ with the
| ICD in the strictest sense of the word, because ICDs are
| deliberately designed to be disabled by magnets.
| oever wrote:
| Great opportunity for a killer app.
| Maxburn wrote:
| Unexpected humor is the best.
| TheCapn wrote:
| 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.
| analog31 wrote:
| 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.
| Forge36 wrote:
| 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.
| codetrotter wrote:
| > Place phone in pants pocket not shirt pocket.
|
| I keep my phone in my pocket but I think some people may be
| hesitant to keep their phone in the pocket for concerns about
| radiation from the phone in proximity to their testicles.
|
| And there may be something to it. In particular if you keep
| your phone in your pocket while using hands free and having
| conversations on the phone. https://www.webmd.com/infertility-
| and-reproduction/news/2008...
| Retric wrote:
| "2.5 centimeters away for 1 hour" that hardly equivalent to
| real world use and likely due to temperature not radiation.
| chimen wrote:
| People browse the internet laying on their back. I am placing
| that phone on my chest quite often while doing so
| meowster wrote:
| When I take a nap and set the alarm on my phone to vibrate
| only instead of ringing, I place the phone on my chest so
| that it wakes me up. Because of this post on HN, if I ever
| get an ICD, I now know better. I wonder how many people don't
| know.
| ssully wrote:
| When you get an ICD, they explain all of this to you. Even
| before the recent warning about iPhone 12's, they explained
| how the device interacts with magnets and to avoid them.
| sandworm101 wrote:
| Patient in hospital. In bed. On back. Phone sits of chest while
| they sleep. Device stops. Alarms. Flashing lights. Nurses
| running. This is a necessary PSA.
| jaywalk wrote:
| A patient in a hospital bed isn't of any real concern with
| this. There will be no alarms or nurses running if the device
| is disabled, only if the patient's heart stops. And their
| heart would have stopped either way, because the ICD isn't
| keeping their heart running. It's there in case it stops, and
| if they're in a hospital bed there will be people around
| ready to attend to them if their heart stops.
| FriedPickles wrote:
| 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."
| philjohn wrote:
| Or 12 inches away if wirelessly charging - so if you charge
| your phone on your nightstand that may cause an issue if super
| close to you.
| Wowfunhappy wrote:
| Idk, with my life on the line I wouldn't buy an iPhone 12 at
| all. Sure, I don't _usually_ keep my phone in my shirt pocket,
| but it's a fairly natural thing to do in some circumstances,
| what if I forget?
| agent327 wrote:
| Nah, that wouldn't happen more than once.
| multiplegeorges wrote:
| That's a wildly flippant response this issue.
|
| "ah, you'll be fine" seriously?
|
| Think of the likely user who has a pacemaker. They are
| probably a man, he's probably in his 60s, 70s, or 80s. He's
| likely not all that familiar with the intricacies of modern
| phones. His kids probably convinced him to get a phone so
| he could stay in touch more easily. That's the audience
| we're talking about here.
|
| It'll happen a lot and while it's happening the lifesaving
| device is fully disabled. That's a big deal.
| btown wrote:
| The user could also fall asleep and the phone could end
| up resting on the chest area - and they may never even
| know that's something to look out for!
| kemayo wrote:
| The joke was "it will only happen once, because it will
| kill you".
|
| (Which is inaccurate, of course, since it sounds from the
| article like disabling a pacemaker in this way will only
| open up an _opportunity_ for your heart to fail.)
| panzagl wrote:
| 90% of my upvote usage on HN is balancing out people who
| have no sense of humor.
| agent327 wrote:
| It's appreciated! :-)
| ekianjo wrote:
| > Reminds me of antennagate
|
| So a problem of phone calls disconnecting reminds you of phones
| causing cardiac problems with people using pacemakers?
| okdjnfweonfe wrote:
| "if you have an implanted defibrillator, don't keep iPhone 12
| in a shirt pocket. [or you might die [vastly sooner than the
| average person]]"
|
| Kinda worth making some drama about it, no?
| droopyEyelids wrote:
| How much drama do we make about other magnets?
| webmobdev wrote:
| What other strong magnets do you keep in your pocket or
| come into contact with regularly, that can interfere with
| an implanted medical device that can cause an organ
| failure?
| pc86 wrote:
| Nobody is forcing anyone to keep any particular magnet
| anywhere. Plenty of people, including successful tech and
| non-tech people, do just fine without smartphones. iOS is
| not a requisite for a fulfilling life.
|
| Note it, inform people about it, mitigate the effects
| where possible and research ways to eliminate the issue
| entirely. But it's not exactly an emergency by any
| reasonable definition and the pearl-clutching "drama" is
| a bit much.
| bdcravens wrote:
| Little, because devices that have strong magnets do a good
| job of disclosing the fact.
| oneplane wrote:
| Is it? Sometimes all you can do is inform. People will still
| ignore it and do it anyway and die earlier (tobacco,
| alcohol).
| jjoonathan wrote:
| Yeah, it's definitely worth the drama, but personally I'm
| more scandalized that biomedical engineers still use
| unmodulated magnetic fields to switch implanted
| defibrillators than I am scandalized by the fact that the
| iPhone emits a magnetic field. iPhones aren't the only thing
| that emits a magnetic field. Not by a long shot. Not by
| accident, not by intent. I'm sure being able to use a magnet
| to switch these implants is handy, but putting inductive
| transceivers on every EMT's toolbelt and in every operating
| room isn't a physics challenge or an engineering challenge,
| not with the amount of money in the medical world. It's an
| implementation challenge, yes, but it's one that should have
| happened 20 years ago. Due to the severity of their work the
| medical community is used to always getting its way, but in
| this case they're the ones who need to shape up.
| DaiPlusPlus wrote:
| Why not a subdermal physical switch that could be actuated
| through the skin? Like a push-button toggle or slider-
| switch?
| da_chicken wrote:
| Probably because people roll over in their sleep and like
| to carry laundry or groceries by holding the bag to their
| chest.
| matthewdgreen wrote:
| The minute you require the presence of a non-standard tool
| for emergency medical attention that could impact an ICD,
| you've guaranteed that it will not be present in some
| cases. It's very likely that such a decision will have a
| body count.
| xxpor wrote:
| But the current situation likely has a body count as
| well.
| mikeyouse wrote:
| For the last xx years of ICDs, ~nobody with ICDs carried
| magnets in their pockets. So the body count of the
| 'current situation' is likely 0. Now that phones are
| ubiquitous and some are including magnets powerful enough
| to interfere, there's a new issue.
| animatedb wrote:
| The magnet is usually used as a mitigator to turn off the
| device in case the device is doing something wrong like
| producing pulses too fast. There is typically RF
| communication that can communicate to the device and can
| often be used to turn the magnet detection off, which means
| that the device will not quit working when a magnet is
| detected.
| tener wrote:
| A warning is good thing, but the drama is less welcome. Blaming
| Apple is absurd too: the defibrillators have built-in kill
| switch that responds to strong magnetic fields. At the time
| where this was designed it was concluded that it is very
| unlikely for such strong magnetic fields to occur in real life.
| Well, that assumption is wrong these days.
|
| It is a responsibility of the designers of the medical devices
| to assure they are safe. Furthermore they naturally have to be
| replaced every few years, so it isn't even hard to phase out
| the outdated design in a coordinated fashion. But I guess this
| costs money and it is cheaper to blame others.
| webmobdev wrote:
| Seems to me like both the cell phone maker and the medical
| device maker want to pass the blame to each other. That said,
| medical devices should get more leeway here - they already
| come with warnings, just like medicines too (e.g. don't take
| with alcohol). When a device is implanted the doctors and the
| manufacturer pass on the warnings to the patient. However,
| they obviously can't pass on warnings about future tech that
| they didn't predict would exist and interfere with their
| device. In such cases, since Apple's new tech is the one
| causing the issues, I feel Apple (and other phone
| manufacturers) need to be more proactive and should publicise
| and caution the public that their mobile phone may interfere
| with implanted medical devices.
| animatedb wrote:
| The magnet is usually used as a mitigator to turn off the
| device in case the device is doing something wrong like
| producing pulses too fast. There is typically RF
| communication that can communicate to the device and can
| often be used to turn the magnet detection off, which means
| that the device will not quit working when a magnet is
| detected. This was used in the past for electric trains or
| other large magnets such as in factories.
| treesknees wrote:
| Pacemakers need to be replaced every 5-15 years as the
| battery wears out [1]. It's not like a visit to the dentist
| either, it's a major surgery. I also think you underestimate
| how rapidly a medical device company can make a dramatic
| change to the design, have it tested and approved, and
| distributed inside everyday people. Yes it's "coordinated"
| but the timeline is extremely long compared to how often the
| phone market is being pumped full of magnets.
|
| For what it's worth I think it's still up to the user to be
| safe and know what they can and cannot have up against their
| chest. But to say that the medical community can just be
| "agile" about this is to really misunderstand how those
| devices are certified and designed.
|
| [1] https://www.hopkinsmedicine.org/health/conditions-and-
| diseas...
| maj0rhn wrote:
| And ICD is not a pacemaker. An ICD costs about $30K. When
| its battery wears out, the battery is replaced, not the
| ICD. So there will be no replacements of already-implanted
| ICDs because of this problem.
|
| Also, it is a big deal to redesign an implanted medical
| device, as it should be. These are not tongue depressors.
| ICDs are the most tightly regulated device the FDA reviews.
| tener wrote:
| Nowhere in my comment did I suggest a timeline for the
| design change to happen. Yes, it will take years, but it
| cannot happen at all if the device manufacturers keep
| blaming others for their poor designs.
| cstross wrote:
| > It's not like a visit to the dentist either, it's a major
| surgery.
|
| My father had a pacemaker, and for long enough to receive a
| battery swap. The battery for that particular model was
| implanted under his shoulder blade; the swap-out was
| performed under local anaesthetic.
|
| The original implantation was a bit more complex from a
| surgical perspective, requiring keyhole surgery and an
| angioplasty to run the wire around his heart as well as to
| implant the battery and controller. But the point is: these
| devices can be installed and expected to perform for
| decades, so the engineering design is of necessity highly
| conservative and has long-term maintenance in mind. It's
| also safety-critical: if the device malfunctions, people
| can die.
|
| PS: a pacemaker is not an implanted defibrillator. (Also,
| my father died in 2017, so what I'm describing is probably
| a decade or two behind the state of the art.)
| maj0rhn wrote:
| Blaming Apple is not absurd. The interaction between magnets
| near the chest and cardiac rhythm devices has been well known
| since at least the 1980s. Even I can remember a published
| case report of a person carrying a stereo speaker, and a
| magnet in the speaker deactivated his ICD.
|
| If Apple were two guys in a garage, you could forgive them.
| But a trillion dollar company... not so much.
| bdcravens wrote:
| Apple did more than just utter a sentence. Everyone who owned
| one of the phones was entitled to a free bumper case, and Apple
| eventually settled a class-action suit, agreeing to pay
| $15/user.
| nycbenf wrote:
| 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!
| dcroley wrote:
| I guess those $10 magnetically attached name tags are bad too
| then.
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