Magnet issuance to PM patients

It would certainly be nice to have more control, but a magnet in the wrong hands?

by Gemita - 2024-09-18 05:03:36

Rch, I sense you are getting frustrated trying to identify a rhythm disturbance and want more control. 

I believe I have seen reports of pacemaker patients using magnets, but I cannot recall the exact circumstances or whether the magnets used were for their specific devices?  I would imagine for security/safety, a patient would not be given a magnet that connects to their personal devices which would be able to read their secure data and enable the operator to change their settings, like pacing mode.  If the magnet got into the wrong hands it could cause mayhem.  

I have a magnet (Reader) that connects to my PM because my pacemaker is not bluetooth enabled.  It then sends data through my iPhone to my clinic, as and when I need to do this.  I did this a few months ago when I was getting significant chest pain and asked them to look for any events.  But of course I cannot see what is read and I certainly do not have any control over what is stored or what my doctors have set up to be stored.  It sounds as though you want more control and I am not sure that such a service is possible or available to vulnerable patients routinely?

I would imagine with your current pacemaker you are able to transmit data on an as needed basis already and ask them to have a look at specific data like battery life, stored ECGs etc. although clearly you wouldn't have the control to trigger an immediate ECG for storage and assessment, particularly if it didn't meet the criteria set up by your doctors for its storage/recording?

I see that acute termination of a pacemaker mediated tachycardia for example can be achieved by applying a magnet to the pacemaker pocket.  Pacemakers are, in general, programmed to respond to magnet application by switching to asynchronous pacing mode, meaning that the pacemaker will only pace at a set rate and will not track atrial activity.   Perhaps this is why you are asking?  I know many of us would like to have access to an on/off button sometimes.

Why don't you tell your pacemaker clinic what you would like to achieve and see what they have to say?  We would all be interested.  On the other hand, ask for longer term event holter monitoring or even see whether you would be a candidate for the implantable loop recorder?

magnet

by Tracey_E - 2024-09-18 09:41:04

I was given one when I got my first pacer in 1994. It's currently in my kitchen drawer covered in tacks and paperclips. I was told it was for emergencies but I don't remember what would constitute an emergency where I'd need a magnet. It can also be used for diagnostics. I think I've used it twice? It's been years. When we were first trying to get my settings right I would swipe the magnet over it whenever I had symptoms and it worked like a bookmark so they knew where to look. It has to be set to do that, it doesn't work all the time. I don't even know if newer devices work like that. Now I just hit the button to send a download. 

Magnet

by piglet22 - 2024-09-18 11:02:56

With Medtronic Ensura, there are couple of things you can do with the magnet.

I would have to look at the manual to see what they are exactly.

I tinker with a lot of things, but unless I had been issed with one by the pacing team with full instructions, I won't be experimenting with a magnet.

Magnets come in all shapes and sizes and strengths. Some of the new rare earth magnets are frightenly strong and can crush fingers.

The reed switch or possibly the Hall sensor, might not take kindly to a very strong field.

Reed switches are mechanical swithes that react to magnetic fields to open or close the contacts. They are generally in a glass package. I've never broken one, but always treat with respect.

Hall sensors on the other hand, are solid state devices, so more robust.

Gemita, 🧲 to patients

by Rch - 2024-09-19 18:35:22

Thanks all of you for your comments!

Gemita, yes, you guessed it right!!😀 My usual rhythm is AsVs unless my HR is over 80 then it's AsVp. I have Mobitz Type 2 block at higher rates. But sometimes I do get some unusual Vp rhythms at rest and it goes on for several minutes to 1-2 hours at times. Rhythm is always sinus with AV interval that corresponds to my paced AVl (200 ms) at a rate of around 70-80 ( my LRL 55. MTR 130). So I assume they are ApVp rhythms. Not sure!! I don't see pm spikes on P waves. Then as I look through the rhythm, I begin to see prolonged AV delay of 400 ms for about 8 cardiac cycles, which then it reverts back to my pre-programmed AV delay 200 ms. These long AV delays are quite uncomfortable to me like feeling-like PVCs!! Also figuring it out whether they are some sort of Wenkeback or AV dissociation was a challenge. Also another possibility was fallback rhythm from ATR . My fall back rate is 70 but wouldn't that have been recorded as an event ? Also, wouldn't a fall back be AsVp? But anyway no events were recorded. After some research, I think I now have figured out what has been going on. It's AVsearch+ feature in Accolade!! ( my Rhytmiq is off). I found out from the Accolade manual that for every 32 cardiac cycles, the AV search + runs a search for intrinsic R (Vs) for 8 cycles with long AV delays. That means I get these uncomfortable search happening almost twice a minute!! It's almost like having 16 PVCs a minute!!!!! Unfortunately I feel every ectopy or arrhythmias unlike some people who don't feel them at all!! It took a lot of Kardia use to figure that out. So, today asked my Device tech to shut off the AV search feature. She warned me that would increase my Vp%, but I didn't really care. I can't live with dozen PVCs-like feeling every minute. So, we decided to slightly prolong my paced AV delay to 220 ms and turn off AV search. We determined I had no retrograde conduction. So, over all, I feel better now which is more important to me at my age (79) than how much %Vp I do. 

I haven't yet figured however why I'm sometimes having these higher heart rates (70-80) at rest! I'm assuming it's probably my SSS acting up? Before the pacemaker, I used to get inappropriate sinus tachycardia. I used Metoprolol Succinate 12.5 mg twice a day for it. So, I do the same, take Metoprolol. 

Regarding the magnet, the feature that programs ' store EGM'  is really a very useful feature especially for symptomatic arrhythmias that are not recorded in the events log! EPs generally don't tell patients about that feature apparently because that would generate too many requests and potential for abuse as well. 

I would issue a magnet to you at any time Rch

by Gemita - 2024-09-20 12:12:51

With your degree of persistence and success in getting to the root of the problem, I would confidently issue you with a magnet  🧲 to add to your considerable arsenal of tools to capture disturbances of rhythm. 

I am glad you have come to a decision on the AV search feature and are feeling a lot better without it on.  I agree, if you feel better pacing in the ventricles, then that suggests to me that this is indeed best for you.  Focusing on “how we feel” is more important than worrying about those numbers.

I discovered something new today too from reading my manual about my Atrial Preference Pacing (APP) feature.  Clearly this feature could be better adjusted from my current values, to help with ectopic beats.  When APP is programmed to On, the device tends to provide a higher ratio of paced to sensed events, which may decrease battery longevity.  A higher setting value though for the Interval Decrement parameter, for example, a value of 100 ms instead of my current 50 ms value, would certainly increase the response to isolated PACs.  I might just ask about this and whether they would consider increasing the 50 ms value. 

If it is any consolation I am also having higher heart rates at rest (80 bpm).  In fact my cardiologist/EP commented on this recently and wanted to increase my beta blocker.  However, as long as I feel well, I am not concerned.  A higher heart rate at rest keeps my ectopic beats under good control and this prevents them from triggering Atrial Fibrillation, so for me a slightly higher heart rate at rest which is still within the normal range (60-100 bpm) is a price worth paying.

Will you be asking your clinic whether you can order and use a magnet to record and store a particularly symptomatic rhythm disturbance in the future, or will you be leaving well alone?

Thank you so much for your post Rch.  I have learnt a great deal as always from your searches.

Atrial Pacing Preference

by Rch - 2024-09-20 23:19:50

Gemita

Thanks! Quality of life is more important to me than worrying about the future risks! I won't worry until worry worries me! 😀

No. I won't ask for a magnet now as I feel good and any episodic palpitation-like feelings that come and go, I will just sit tight on them as long as they are not too bothersome. Beta blockers do help me with some of those. However, if I have any symptomatic palpitations precipitated by the changes in my new AV delay etc, I will definitely ask my provider if I could use a magnet for the 'store EGM' feature. If he's not too comfortable with that idea, then any reprogramming changes made on that visit, I will make sure I could walk-in to the clinic any day if symptoms persist! 

I read about the APP and ProAct in the B.Sci manual. The algorithm is very mathematical and might definitely work to keep PACs at bay and I think you should try that if the ectopics really bother you. It might make a world of difference  in your quality of life. If it does not work, you can always reprogram it back to your current settings. Hopefully you will have access to the clinic in a reasonable time frame of about say 2-3 weeks and not ' the next available would be in Feb 2025' sort of thing! 

I wish you best of luck! Thanks again for all your advice and encouraging words!