Automatic safety switch from bipolar to unipolar

Oh gosh!

by Lavender - 2024-04-16 11:33:56

I can't answer your question but I have to say that I am quite impressed with the age of your leads!  🤩

I think this is a trapdoor function

by crustyg - 2024-04-16 11:37:22

It's a smart piece of design - your lead is no longer working adequately in bipolar mode, so to stay as a useful lead it's been set to unipolar by the device.

I doubt that your EP-team would set it back to bi-polar with that impedance.

I think you're correct.  Time for a new lead +/- some expert lead removal.  Centres that do a lot make it pretty much safe and routine, although we all know that it has a very, very small chance of going badly wrong, which is why the true experts have a lot of skill on immediate standby.

Best wishes.

Interesting dilemma

by Good Dog - 2024-04-17 13:48:30

You obviously have a couple of options available. I would think that at your young age that extraction may be the best option. I have to think that your vein is occluded, but if not they may be able to fit another lead in the vein. You will need a veinogram to determine that. If you do need an extraction, those old leads will be difficult to extract, so you need to be sure to trust that procedure to someone with a lot of experience. They could move to the right-side, but a couple of my Doc's at the Cleveland Clinic advised against it for a couple of reasons.

I find it interesting that my leads are about the same age as yours. My first two leads were implanted in January 1987 in New Jersey. One is still in-use (atrial #4016) and the other RV lead (#5024M-58) replaced a recalled lead that was capped in 1995. I would not be surprised if we have the same leads including the one that was recalled. I also found it interesting that they replaced your Medtronic device with a St Jude device? I am already on my 4th Medtronic generator implanted just last month. I would be interested in knowing more about your condition such as your EF and lead placement since our length of time being paced is so similar. I see that you are in Pennsylvania while I am in Ohio; perhaps not too far away. Although, I've lived in Lancaster and Chambersburg as well as central NJ near Philly. I'd also be curious to know where you are in Pennsylvania. If O.K. with you I'd like to PM you?

Sincerely,

Dave

interesting

by dwelch - 2024-04-17 16:34:38

I had two leads put in in 85 and the doc broke one in 97 and so then there were three. (one capped in 97).  Now there is four and that was a concern.  So we have some similar aged leads, would be halarious if they were the same brand.

I dont think five will fit without taking one or two out.  Or moving to the other side.

I was wondering if anyone knew if the device auto returned to bipolar and this was a temporary event and it had not repeated.  But I suspected it could only be tested/reversed in the office.

I have had what three medtronics, then st jude and now a boston scientific.  Current doc/office mix it up, if all patients are medtronic and there is a medtronic problem then all patients have a problem if only a third then ony a third.  Makes sense.  Was told the st jude would have a longer battery life 14 instead of 10 or so, but didnt get to find that out because of my EF dropping into the 30s it was time for a bipolar.  Which...is now unipolar...But appears to be working.  (yes the biventrical not only stopped the EF from dropping further but it climed back up, I think better than it has ever been.  Implying IMO it was from right side pacing for decades.   Always had a low EF, just going from 40s to 30s got their attention)

I didnt find out about the st jude until the rep, in the O.R. introduced herself, Im from st jude with your device, etc.  And only because the ekg machines were acting up that I was not in twilight.  I was fine with it, just wish they had told me before the last minute, or explained it after the fact.  Apparently I had a discussion (not sure about what) after the surgery, but I remember zero, was still out of it I guess.  Wife said he came in we had a talk.

Not sure which the boston sci or the sj jude, I guess I had too perfect of an atrial lead (the 1997 lead) that there was feedback that the pulse generated by the device as actually confusing the device.  Doc told me she literally spent the entire weekend going through every beat of my halter recording to find it (Decades with pacers and never one complaint until then, so she wanted to figure it out so she said).  They called in a rep/tech and all stood around as he showed them what he was seeing and what setting to change.

I have a mixture of brands of leads too.

PM is fine.

more info

by dwelch - 2024-06-15 01:46:16

Not many posts on this, and I just saw my EP, first visit since this happened.

Had a very good nurse/tech that I could easily talk to.  Even as an engineer the terms unipolar/bipolar and now Dr. Google makes less sense as what some pictures are showing/implying bipolar vs unipolar are not what I have and I have my old devices so those pictures are quite wrong.  The one other post on this topic the commenter talked about bipolar being more efficient, etc.   And I would think so too with what I assume bipolar means, but was thinking it meant something else.  Basically the 37 year old lead's impedance went high enough that it triggered the device to switch from bipolar to unipolar which does not mean unused, it just changes how the signal is driven.  In my case, and not necessarily for everyone falling into this, going unipolar on that lead did not cause an increase in battery consumption.  The battery estimate which again everyone should know any units other than weeks is not real, still says 3 years a year after it said 3 years. 

She also said this does not automatically mean we go for removal.  I have four leads, using three, one was broken 30 years ago.

Another thing that folks might find interesting is that number four was cut short (I am on number five) because my EF which since we started measuring it decades ago was always mid/low 40s and had dipped into the 30s and got to mid 30s.  So number four came out way early and number five is a biventrical (needed another lead thus the four).  From my understanding of her initial explanation that we were trying to stop it dropping, if it was related to decades of right side pacing then biventrical would help, if it was something else then it wasnt.  Turned out due to circumstances it was 18 months from echo through device to then a year before the next echo, and not only had it stopped dropping but it went up into the 40s or even 50s.  This years echo is in the 60s which is higher than I have ever had from an echo.  Blows me away, but...is what it is...

I have device number one through three, at number four they legally had no way to give it to me.  Those first ones all had two interfaces for two leads.  The pictures you may see if you ask Dr Google imply that a bipolar is a lead with two connections into the device, so bigger lead, etc.  That is not what i have yet my 37 year old lead is/was used bipolar.  Fairly certain I know what that does mean, but in any case.  I was wrong, the lead is being used, the impedence is still high in that mode so it will remain unipolar, but doc came in and said "Everything looks good".