PM replacement with ICD

Hello expert friends,

I've had a PM for bradycardia and complete heart block for three years and learned this week that I have a mutation known to cause PRKAG2, a rare cardiac glycogen storage disease that in some respects mimics hypertrophic cardiomyopathy (indeed, I have a thickened septum). With this diagnosis, my doctor is urging me to have my PM extracted and replaced with an ICD, as PRKAG2 is associated with sudden cardiac death (probability unknown, as there are simply not that many cases available for study). I'm guessing no one else on this forum has PRKAG2, but has anyone had to replace a PM with an ICD? And, if so, did you opt to leave the old PM lead in place or have it extracted? I'm told the choice is mine and am not sure which way to go. 

Any thoughts welcome!


Lots of experience here

by crustyg - 2020-12-11 04:40:02

Probably the commonest route is PM=>CRT-D which is much the same.

Unless there's some compelling reason for extraction (in which case you need it done by an expert centre that does 100+ each year - this is *not* a procedure for have-a-go amateurs) leave any redundant lead in place.

The additional risks of leaving in a lead that's been there for 3years (retained foreign body in the bloodstream) are zero, I estimate.  If you were considering the risks of leaving in some leads when everything else is being removed, that would be different - but you're not.

For me, the only possible benefit to having a redundant lead removed would be if the lead is known not to be MRI-compatible, but a lead implanted in 2017 would almost certainly be ok.  Having a small, but real risk of SCD isn't great: knowing that you've got a device ready to (probably) save your life would help ease *my* mind.  I would go for the ICD in a heart beat.  Boom, ching!

Hope all goes well.

My thoughts

by Gemita - 2020-12-11 04:54:03

Dear Heartbeat26,

Thank you for your message.  You sound extremely positive and in complete control of your new diagnosis and I am sure this will help you to come to the right decision.  Have you had a meaningful discussion with your doctors who will know your health history best, who have perhaps discussed the pros and cons of leaving the leads in place as opposed to extracting them?  I expect you have.  You should really be guided by them in your decision making and I would be quite surprised if they haven’t offered an opinion on which way they would go?

What would I do in your situation?   I have not had a lead extraction but I would very carefully consider all the pros and cons of the potential risks of lead extraction compared with the potential risks, over time, of leaving your leads in place.  Although leads can be left in place without harm and I see from this site that many do, and quite successfully too, over time there may be a steady cumulative risk of infection/trauma to the vein like an occlusion for example, necessitating immediate removal which would increase the risks of extraction and other complications at that time.  I feel the addition of more leads into the same vein increases the likelihood of vein occlusion and increases the difficulty in placing additional leads in the future.

However, the other side of the coin is, if it ain't broke, don't fix it.  It seems that new leads can be successfully placed in the same vein as a redundant lead without undue harm, particularly if the vein is healthy and can comfortably accommodate a second or even a third lead.  Also a new lead can be placed in a different vein, even in a new location, leaving the old lead safely where it is, so there are a few choices. You need to consider as well the urgency of having an ICD placed, without complication, to protect you and it would certainly be easier to feed new leads beside old ones to get the job done faster. 

If you decide on lead extraction, it is very important that your pacemaker team is experienced in lead extraction (and it sounds as though they probably are) because lead extraction can be a very high risk procedure in inexperienced hands.  I would want to know how many lead extractions your team has carried out and how successful they have been.

I do wish you the very best. 


Thank you

by heartbeat26 - 2020-12-11 09:37:08

Thank you, Gemita and Crustyg,

As always, I find the comments from members of this site to be extremely helpful. In fact, my EP did not express a preference about whether I should leave the lead in place or have it extracted. He said the reason to leave it in place would be so that I would be able to have MRIs in the future, should the need arise, but Crustyg points out that a 2017 pacemaker lead is likely to be MRI-compatible already, so I need to find out whether this is even an issue for me. (This EP was not the one who performed my PM implant, so he in fact may not know whether my leads are MRI-compatible.) Regarding my diagnosis, I actually feel overwhelmed by it, am struggling to process it, and am anxious to have my children tested as it is an autosomal dominant condition that I fear I may well have passed on to them. 2020 has been a hell of a year. Thank you both.

I do understand your very real concerns

by Gemita - 2020-12-11 11:24:17

Hello Heartbeat26,

I can see your doctors are doing everything they possibly can to ensure that you remain safe.  Hence the ICD to stop a dangerous arrhythmia or to prevent SCD.  While I understand completely your difficulty in coming to terms with your diagnosis, the outcome for each patient will be so individual, and I wouldn’t assume the worst at this stage for either you or for your children in the future.  I would be reassured that with a confirmed diagnosis you will be safely monitored and treated in a timely fashion, so that you can look forward to a good quality of life.

I have faced some difficult diagnoses in the past and when I was told about everything that could happen to me, I was initially overcome with dread, but things have turned out to be completely different because of the treatment I received.  I hope it will be the same for you too. 

By the way, I too feel fairly confident that your 2017 leads will be MRI compatible, so you could probably afford to leave the leads well alone and in place and focus on getting your ICD implant in as soon as possible to protect you.  

Take good care and try not to worry, that way you will give yourself the best possible chance of staying well.

Lead extraction and MRIs

by AgentX86 - 2020-12-11 13:36:43

Crusty, correct me if I'm out of date but it's my understanding that a capped lead is an automatic disqualification for MRIs , whether the leads are MRI "safe" or not. Indeed having a capped lead is covered under the  "conditional" part of the "MRI-conditional" wording (it's not "MRI safe" or "MRI compatible"). 


"Our results support the current PM manufacturers' policy of conditioning the MR compatibility of their systems to the absence of abandoned leads (including leads from MR‐conditional implants)."

Of course, in an emergency all bets are off.


by Gemita - 2020-12-11 16:23:09

Just had a quick glance at the link which is dated 2014.  Thank you for this.  I wonder if there is any current, more up to date information regarding MRI safety with a capped lead?  Interesting though and needs to be taken up with the pacemaker manufacturer to perhaps check the ideal safety settings/additional monitoring required in the event of needing an MRI.  So many things to consider


by AgentX86 - 2020-12-11 23:47:19

The physics won't change.  The issue is the MRI's RF feild causing heating of the capped leads.  Unless there is some other means of capping the lead, I don't see this changing.

Changes the decision matrix

by crustyg - 2020-12-12 16:40:30

Thanks Agent, I wasn't aware of this.

For me, that would change the decision towards removal.

I think Ian mentioned managing to charm his imaging team into an MRI that wasn't strictly within the guidelines and he reported significant heating.

You know you're wired when...

Friends call you the bionic man.

Member Quotes

I’m healthy as a horse because of the pacemaker.