PM 3520B Heart Pacemaker Potential Interference

[Douglas Quetin]

I have a PM 3520B with an inverter. When I use the lathe my shop radio and the radio at the house 200' away go directly to static. Shop and house have separate meters.

Recently, I had a heart valve replacement and a pacemaker installed and am worried about interference of the latter. I obviously don't want the pacemaker malfunctioning. Although I will be discussing this with the manufacturer, I was curious if any of you all have looked into it. My apologies if this has been addressed previously; admittedly I am a bit hit and miss on the forum, especially lately. Frankly, I just like turning too much to be at the computer.

This is my 11th day without a lathe tool in my hand and I probably have 30 more to go. Talk about cruel and unusual punishment. At least my karma sheet ought to be nicely balanced.

Thanks for you attention.

[Dennis Nagle]

There is a difference between radiated interference and line interference When you start the lathe, take the shop radio and wave it around the lathe. If the interference does not change, it is coming down the power line. You might want to call PM and see if they have advice. Either way, it should not be emitting any interference.

[Brian Kent]

Thank you Doug for bringing this to the forum. I have not seen this question before and will be interested in the answers from here and from the manufacturer.

(If I were a less caring person I would tell you about my friend, Elwood, who said after her got his pacemaker every time a beautiful neighbor jogged past him the garage door would open. Sorry.)

[Jeff Gilfor]

In my day job, I'm a Cardiac Anesthesiologist (MD), so I do know what I'm talking about here. I'm guessing you had your aortic or pulmonic valves replaced (more likely the AV); those are the ones that'll knock out the normal heart conduction system, requiring pacer support post-op. Hope you're doing well. Those patients generally do.

That said, there is absolutely nothing to worry about.

Typical electrical equipment are examined by the IEEE (elctrical engineering trade group, and either approved or not. You are hard pressed to find a device that's not approved.

All electromagnetic radiating equipment (radios, microwaves, etc.) have strict standards set by the FCC (even the ones imported from abroad... or from a guy for that matter ;-)). Those standards are set forth in the Code of Federal Register (CFR).

All medical devices are codified in the CFR as well, and fall under the auspices of the FDA and FCC, with the FDA taking priority. These instruments and devices satisfy very stringent shielding requirements. About ten years ago, there was great concern about EM interference with ventilators, pacemakers, and the like from cell phones. Back in the day, they were analog and much higher output back then than today. Anyway, there were several good studies done, and no pacemakers were ever able to be messed up using cell phone interference or a special radio generator they used for testing either. I actually wrote an article about it back then (do a search on my name to read it if you care).

Anyway, commercially available inverters and power supplies don't pose a threat to pacemaker patients. Besides, every pacemaker today will switch to some safe default settings in the event of any problem with the sensing function (newer pacers sense normal cardiac electrical signals, and only step in when necessary).

So, sorry for the long drawn out explanation; bottom line is turn as much as you want. Of course, if you're not convinced, I'd be happy to relieve you of the PM-brand pacemaker killer you have... for a nominal fee of course.

Actually, as an aside, you are far more at risk for bleeding injuries and blunt trauma (like a big bowl blow up, without good safety equipment), due to the coumadin you are likely on now that you've had a new valve (most are mechanical, requiring lifelong anticoagulation).

[Roger Chandler]

My wife is a cardiac device nurse.......we also have a gentleman in our club who went through this very issue with a 3520b.........the device manufacturer sent a representative out to a local turner who has the 3520b and tested for interference with appropriate electronic equipment...........no leak or bleed of radio frequency...........the manufacturer was Boston Scientific...........his situation actually was in a write-up in the AAW journal..........look it up, if you wish! The turners name was Marsden Champaign. [he is known by all of us as "Mars"]

You should be fine!

[Dave Mueller]

Douglas,
First, 3 phase motor controllers like those used on variable speed lathes, are notorious for generating RF (radio frequency) emissions, both conducted in the wires and radiated by them. This is mainly in the wires running between the controller and the motor, although there is some radiation back up the power line from the controller to the wall plug, which could also generate some radiated RF. A lot of this radiated RF can be eliminated by shielding the wires from the controller to the motor, if it is not already done. This should be done by someone knowledgeable in electronics so you do not cause unwanted ground loop currents.

I used to work for Medtronic (a pacemaker manufacturer) many years ago. Back then, pacemakers were very susceptible to radiated RF. They have gotten much better since then. The potential issue is that the radiated RF is picked up in the pacemaker lead that runs between the pacemaker and your heart. Pacemakers are designed so that they sense the very low level electrical activity generated by the heart when it beats and then decide to pace or "inhibit" (stop pacing so that it does not interfere with the normal heart beat). When the heart beats too slowly, the pacemaker senses this low rate and sends pacing signals down the lead to make the heart beat at a normal rate. Some people are "pacemaker dependent", which means if the pacemaker does not pace the heart, the heart rate can fall low enough to cause dizziness or even fainting.

Please do not take advice from anyone other than your cardiologist. Only your cardiologist can determine if there is a risk from RF inhibition of your pacemaker. This is probably not an issue, but you should check to be sure. You might ask your cardiologist to contact the pacemaker manufacturer to determine how sensitive your specific pacemaker is to radiated RF.

Sorry about all the technical mumbo-jumbo, but your question was a valid one.

Dave

[Roger Chandler]

Dave..........most cardiologists rely upon the info that the manufacturer of the device gives them.......it used to be standard advice given to patients about interference from electric motors and other power sources like chainsaws, etc. Being as my wife works in this area closely with cardiologists [six of them, in fact] and closely with the device manufacturer representatives on a daily basis.........and the fact we had two patients who were turners who faced this issue and I am a turner, we contacted the device reps.....

They got info to the home office of Boston Scientific, which sent a rep to the home of a local turner with a 3520b, and came back with the word it was no leakage and interference with the particular model in question of the ICD...........given that, an older pacemaker may not have the same safeguards in place as far as shielding, etc, but to be safe the turner in question should ask about the specific model number of their pacemaker/ICD and get as much info as possible........

That being said.........most cardiologists do not deal in this area of turning, and will not go to the lengths necessary to find out for the patient.....they are just too busy to fool with it.............one of the cardiologists that my wife works with is also a turner with a 3520b...........and the Manufacturer's representative was also very helpful to find out info..........

Likely any pacemaker/ICD implanted in the last 6-8 years will be fine........again it should be verified as much as possible with the manufacturer as to the specific model number just to make sure!

[Joe Kaufman]

From a friends experience 2-3 years ago, one of the few specific things to avoid was a chainsaw. I don’t remember if he specifically mentioned MRI but I would assume that is the case.

[Brian Finney]

Douglas,
Jeff’s last comment is timely



Actually, as an aside, you are far more at risk for bleeding injuries and blunt trauma (like a big bowl blow up, without good safety equipment), due to the coumadin you are likely on now that you've had a new valve (most are mechanical, requiring lifelong anticoagulation).

Locally, a guy drilling the wall found a live cable – he was thrown or fell backwards, banged his head – bled to death. Funeral was last Friday.
He was taking warfarin aka Coumadin.
Maybe time to consider more substantial head and face protection.
Brian

[Ralph Lindberg]

In my day job, I'm a Cardiac Anesthesiologist (MD), so I do know what I'm talking about here. I'm guessing you had your aortic or pulmonic valves replaced (more likely the AV); those are the ones that'll knock out the normal heart conduction system, requiring pacer support post-op. Hope you're doing well. Those patients generally do.

That said, there is absolutely nothing to worry about.

Typical electrical equipment are examined by the IEEE (elctrical engineering trade group, and either approved or not. You are hard pressed to find a device that's not approved.

All electromagnetic radiating equipment (radios, microwaves, etc.) have strict standards set by the FCC (even the ones imported from abroad... or from a guy for that matter ;-)). Those standards are set forth in the Code of Federal Register (CFR).

All medical devices are codified in the CFR as well, and fall under the auspices of the FDA and FCC, with the FDA taking priority. These instruments and devices satisfy very stringent shielding requirements. About ten years ago, there was great concern about EM interference with ventilators, pacemakers, and the like from cell phones. Back in the day, they were analog and much higher output back then than today. Anyway, there were several good studies done, and no pacemakers were ever able to be messed up using cell phone interference or a special radio generator they used for testing either. I actually wrote an article about it back then (do a search on my name to read it if you care).

Anyway, commercially available inverters and power supplies don't pose a threat to pacemaker patients. Besides, every pacemaker today will switch to some safe default settings in the event of any problem with the sensing function (newer pacers sense normal cardiac electrical signals, and only step in when necessary).

So, sorry for the long drawn out explanation; bottom line is turn as much as you want. Of course, if you're not convinced, I'd be happy to relieve you of the PM-brand pacemaker killer you have... for a nominal fee of course.

Actually, as an aside, you are far more at risk for bleeding injuries and blunt trauma (like a big bowl blow up, without good safety equipment), due to the coumadin you are likely on now that you've had a new valve (most are mechanical, requiring lifelong anticoagulation).

I'm quoting Jeff for the only because something should be made clear. There are DIFFERENT regulations for consumer items then commercial/industrial items. The emission standards for consumer devices is much more strict then commercial devices. Which is why the electronic lathes (Nova DVR, PM, etc) all trash your AM radio, but aren't considered "bad", because they are considered commercial/industrial and not consumer devices.

As Jeff points out, pace-makers have to be tolerant enough of EMI/RFI due to emissions from cell-phone and commercial/industrial devices. I would suspect that no pace-maker sold in the US would fail to meet these criteria. But, as others point out, check with YOUR doctor on the matter.

By way of my background, I am a EE with 30+ years working extensively in the EMI/RFI area, I hold (or have held) just about every radio license there is/was (some on longer exist)

BTW, this subject comes up every few months on one or another forum. I have yet to hear of authoritative source that has seen an issue, but it could happen.

[Jamie Donaldson]

You mean a chainsaw can be a source of electrical interference with other electronics such as pacemakers? :eek:

[Jeff Gilfor]

Gotta be a little annoying here, but Cardiologists generally don't know squat about how the devices they place react to EM radiation interference. That information, if desired, can best be provided by the manufacturer of your device. Everyone with an implanatable pacemaker or defibrillator has a wallet card stating the exact device, serial number, and the customer support phone number. Give them a call. They don't mind. They make a huge amount of money for making those little gems.

Let's be clear. Currently, pacemeakers are safe around industrial and personal use woodworking equipment. Only very old units could be at risk. Since the lifespan of these devices is about 7-10 years, no one alive right now should have one of those inside of them.

This from the AHA, regarding pacemakers and equipment (italic bolding is mine):

"Consumer appliances and electronics: in general, have not been shown to damage pacemaker pulse generators, change pacing rates or totally inhibit pacemaker output. Several of these devices have a small chance of causing interference by occasionally inhibiting a single beat. However, most people can continue to use these household devices without significant worry about damage or interference with their pacemakers.



CB radios or amateur ("ham") radios


Electric drills


Electric blankets


Electric shavers


Heating pads


Metal detectors for recreational use


Microwave ovens


TV transmitters and remote control TV changers


MP3 players (but headphones should be kept at least 1.2 inches or 3 cm away from the device)


Office and light shop equipment: most pose no risk to your pacemaker.



Computers


Typewriters

[*=1]Copy machines
[*=1]Woodworking shop tools
[*=1]Light metalworking tools"





What you DO need to be carefull around is welding equipment, high power magnets (MRI's), large electrical generating equipment (turbine generators, HV transformers, etc.), radars (big ones, not microwave ovens),and some lab equipment like electron microscopes and spectroscopes. They produce high powered high frequency magnetic fields that can induce currents in the leads going form the device to the heart. Pacemakers will still filter these currents, and likely not produce any long lasting problems, but it's possible that they could mimic normal heart signals that might cause the pacemaker to change modes (they are designed to do that under certain situations).

Again, bottom line is... chill, but please don't show up in my ER with a big head injury from that poorly chucked vase you were hollowing.

[Dave Mueller]

Roger,
I agree with you that it may be difficult to get definitive info from a cardiologist on a specific pacemaker's sensitivity to RF. My comment, which probably was not very clear, was more to the question of whether a person is pacemaker dependent or not. That can only be determined by the cardiologist. If there is an RF problem, a pacemaker dependent person is at higher risk than someone who is not. There are so many variables here that a definitive answer for the average woodturner is probably almost impossible to resolve. Regardless, I would at least talk with my cardiologist about it.
Dave


Dave..........most cardiologists rely upon the info that the manufacturer of the device gives them.......it used to be standard advice given to patients about interference from electric motors and other power sources like chainsaws, etc. Being as my wife works in this area closely with cardiologists [six of them, in fact] and closely with the device manufacturer representatives on a daily basis.........and the fact we had two patients who were turners who faced this issue and I am a turner, we contacted the device reps.....

They got info to the home office of Boston Scientific, which sent a rep to the home of a local turner with a 3520b, and came back with the word it was no leakage and interference with the particular model in question of the ICD...........given that, an older pacemaker may not have the same safeguards in place as far as shielding, etc, but to be safe the turner in question should ask about the specific model number of their pacemaker/ICD and get as much info as possible........

That being said.........most cardiologists do not deal in this area of turning, and will not go to the lengths necessary to find out for the patient.....they are just too busy to fool with it.............one of the cardiologists that my wife works with is also a turner with a 3520b...........and the Manufacturer's representative was also very helpful to find out info..........

Likely any pacemaker/ICD implanted in the last 6-8 years will be fine........again it should be verified as much as possible with the manufacturer as to the specific model number just to make sure!

[Brian Finney]

Jamie

My thinking is that the chainsaw risk is associated with cutting the femoral artery – the big one in the thigh - with the chainsaw.
Bad for anyone– really bad for someone on blood thinners.
Solution of course is to wear the trousers designed for chainsaw use . http://www.youtube.com/watch?v=Ah-FmYnaIWw (http://www.youtube.com/watch?v=Ah-FmYnaIWw)

Brian

[Roger Chandler]

Roger,
I agree with you that it may be difficult to get definitive info from a cardiologist on a specific pacemaker's sensitivity to RF. My comment, which probably was not very clear, was more to the question of whether a person is pacemaker dependent or not. That can only be determined by the cardiologist. If there is an RF problem, a pacemaker dependent person is at higher risk than someone who is not. There are so many variables here that a definitive answer for the average woodturner is probably almost impossible to resolve. Regardless, I would at least talk with my cardiologist about it.
Dave

Thanks Dave........a further note of clarification.......a pacemaker dependent person........likely one who has had an oblation procedure done, or one for other reasons, do need to check with the device manufacturer.........and their cardiologist. Likely the cardiologist will refer the patient who wants this info to the device manufacturer anyway, but not all of them will do so........the patient is ultimately responsible to educate himself/herself on the particulars of their device........as was mentioned by Jeff Gilfor above, each patient who is implanted gets an ID card with the model and serial numbers on it, and can easily follow up if they have concerns.

There was a write up in the AAW journal last year on one of our club members!

[ron david]

are your buildings older with an older electrical system . mine did that under an older electrical system. but disappeared when I moved into newer premises. the other alturnative is going to a treadle lathe. the static will disappear and you should get health benefits from it. I think that you can get a static suppressor from the electric motor manuf. I could have gotten one for my toshiba motor. I used a toshiba controller also. this goes back into the 90's. I would ask your Dr. that installed the pacemaker if it can interfere with it. if anyone is going to know he should
ron
sorry I didn't see the rest of the posts when I replied

[Dan Hintz]

Typical electrical equipment are examined by the IEEE (elctrical engineering trade group, and either approved or not. You are hard pressed to find a device that's not approved.
Everyone has hit on all of the other points, so I'll hit this one...

The IEEE does not examine any equipment. The IEEE is a professional association for electrical engineers, as well as a publisher of a multitude of EE-related technical journals. They have zero to do with equipment, only keeping the professional name professional.

[Jim Burr]

This came up not to long ago on SMC. Contacting the manufacturer is your only viable option.

[Chris Studley]

IEC/ISO standards for Medical devices(IEC 60601-1, Medical electrical equipment; ISO 14708-5, Active implantable medical devices—Part 5: Circulatory support devices) include as a requirment compliance with the EMC collateral standard (IEC 60601-1-2) these are well understood, fairly straight forward and are not new to the industry.

These General and Particular standards are based on the type of device. Corresponding essential performance of the device is verified prior to marketing of devices. Given that pacemakers are considered "life supporting equipment"(regardless of individuals needing only pacing on demand) these essential requirements are adjusted accordingly. The intention is that patients can resume normal daily activities, as appropriate. Safety concerns such as static discharge are addressed as well as the need to be functional after a defibrilliation event which can be as much as 5 kV or +/- 2.5 kV. (this is obviously a concern, and considered likely when we are talking heart issues). So My gut says that the MFR has these issues well in hand.

However many pacemakers and other implantable devices can be programmed or queried for data via a near field programmer, usually placed on the skin over the implant. So due dilligence is prudent, but these programmers are usually high frequency and AC frequencies (50/60 Hz) are likely well protected against.

My guess is that this is a conducted emission vs radiated as I assume that the controller is in a metal box of sorts and likely referenced to earth ground(for this EMI reason). I am unfamiliar with the applicable safety standard that the 3520 falls under, but mostly there are some level of EMC requirements in all product catagories. Given that you are not plugged into the wall also this shouldn't be conducted to you. I would verify your power source is proper as to not defeat the safety built into the Lathe.



Good Luck.



I would verify that all connections and grounding lugs etc are in order.

[Ken Fitzgerald]

Contact the engineering department of the implant via their customer service department. The implant manufacturer should be able to answer your questions.

[Douglas Quetin]

Well gentlemen, I really appreciate the responses. I will be talking to my cardiologist, pacemaker manufacturer, and PM for sure and let you know if any of their responses vary with the collective wisdom you have provided.

You were right on Jeff, AV replacement with mechanical valve and about 5" of the aorta. I do take a lot of precaution these days due to the scars of the past, but particularly now when on coumadin. I use a full helmet with supplied air, very sharp tools, and abide by (well, pretty much) working hours. The biggest problem I find now is floor clutter going unseen with the helmet on.

Nonetheless, that you all for your time, it was much appreciated. If you are ever in Acampo, CA, come by the shop and we'll swap some lies.

Doug

[Paul Gilbert]

I have a PM 3520b, a pacemaker and take Coumidan. No one ever told me not to use the lathe, but did warn me about chain saws. As best I could determine they were most worried about the vibration from the chain saw dislodging the wires to my heart. I now use both the chain saw and the lathe and have never had a problem.