Risks of long-term RV pacing

I have total heart block, but my Sinus Node is working OK. Consequently, my Biotronik Enitra 8 PM is operating in Right Atrium Sensing/Right Ventricle Pacing mode: effectively bypassing the AV block.

This is now working well and I was feeling optimistic about the immediate future until I read recently about the risks of long-term RV pacing! Various unpleasant sounding consequences, including heart failure and death, are apparently possible. My pacing burden is necessarily 100%.

I wonder if some of you knowledgeable regular contributors could put this into perspective for me. Thanks.



by Lavender - 2023-09-07 20:28:46

I used to look online like you're doing but it depressed me. I realized that without my CRT-P device, I would already be dead. I was having longer pauses that were more frequent. I went unconscious 26 times in six months. The last two events, included near death experiences. The last pause was 33 seconds. I have complete heart block and left bundle branch block. I am 100% dependent on my device. 

Whatever detriment there is to having it...so be it. I need it or I die. No sense worrying about the dangers. It's in me to stay. 

Heart Block

by USMC-Pacer - 2023-09-07 20:40:05

I dunno, but some folks here have written they have been paced for decades. Some are on their 4th and 5th devices. I recall some claiming to have been born with complete heart block requiring a pacer and now in their 40s and 50s. I think that with anything else, technology improves and overcomes alot of the past complications. Others will chime in.


by Tracey_E - 2023-09-07 23:28:46

Bottom line, the risks of not being paced FAR outweigh the risks of being paced.

Real talk...

- if you have a newer pacer, the way they place leads now is much more gentle on the heart than it used to be which decreases the chance of long term problems

- according to my ep, odds of heart failure from pacing are well under 10%, and he feels a chunk of those would have had heart failure with or without pacing so the actual number is a lot lower than that.

- also from my ep, he said if someone is paced 5 or more years without a drop in function,he almost never sees it happen later. 

- heart failure is no longer a death sentence. We are monitored so it would be caught early and treated. 

I'm on my 5th device and have been paced 29 years. My leads are placed the old way. I have paced every beat since 1994 when my first one was turned on. My ejection fraction (how they measure function) is exactly the same as it was when I got my first one.

Right ventricular pacing

by Gemita - 2023-09-08 02:32:24

Repero, when I started my journey with arrhythmias and was given my treatment options, I was told one option would be an AV Node ablation where the fast signals from the top chambers would be prevented from passing through the AV Node to push my ventricles too fast, effectively causing a heart block.  I would then become pacemaker dependent and would be paced in my right ventricle (RV).

At that time my EP told me they would watch me carefully for any signs of dyssynchrony between my heart chambers and if I was found to be showing signs of difficulty, for example having heart failure “symptoms”, he would immediately upgrade me to a CRT (cardiac resynchronisation therapy) pacemaker.  

He further explained that in his long experience if heart failure due to RV pacing was going to occur, it would occur within the first couple of years of pacing, when action could quickly be taken to restore pacing synchrony.

I then asked why I couldn’t have a CRT pacemaker from the start should I opt for an AV Node ablation and he again reminded me that they would watch me carefully and only intervene if heart failure symptoms were to occur at any stage in the future.  For example many patients paced in their RV for years never go on  to develop heart failure and let us be clear, no intervention is without risk, so if it isn’t broken why treat it?

Repero I can understand your concerns about a high percentage of RV pacing but heart failure symptoms is certainly NOT inevitable from RV pacing or a death sentence any more and action would quickly be taken to upgrade you to a CRT pacemaker should signs of heart failure ever be seen.  Keeping a watchful eye on things will be done to keep you safe, have no doubt.  Watchful waiting is something that our doctors do all the time with many diseases and can often be the best approach.  Echocardiograms will be needed for this and an eye will be kept on your ejection fraction to pick up any early signs of a problem.

So don’t worry about something that may never happen and if it should, action can quickly be taken to correct the situation, restore synchrony and reverse heart failure symptoms.

If you are ever concerned about any new symptoms you are getting, always seek early advice, but if you feel well, then I would live your life without concern.  Remember Repero, stress and fear about what might happen can also be a "major" risk factor for serious health problems if they are not firmly controlled.  

I send my best wishes as always

Grateful thanks

by Repero - 2023-09-08 04:14:35

Thank you everyone for your wise and sensitive responses to this post. This is a great club!

Yes, you are right; worrying about what might never happen is pointless, and gratitude for the good that my PM has already done me is the most appropriate attitude.

I needed this re-orientation, so thanks again.

I Guess I Am in That Boat Too

by Marybird - 2023-09-08 09:11:58

I just had my in-office pacemaker check a few days ago, and the technician reported a 90% atrial, and 98% ventricular pacing rates. I knew the technician last year had turned off the "VIP" ( ventricular intrinsic pacing) and/or AV delay ( don't know if these are the same or two separate settings) as she explained I was having some heart block ( she explained the process but its still fuzzy to me). She said this would result in some ventricular pacing, probably quite a bit, but I never see the results of my remote monitor pacing results ( I could ask but haven't) and I feel ok.  

Even though I was informed ahead of time about the ventricular pacing, it still threw me for a loop, but then, I was that old lady who was skeptical about whether my sick sinus syndrome and associated miseries were bad enough to even need a pacemaker four years ago when I got it. 

So, I started reading, like Repero, and Lavender, and am in the process of reassuring myself that I'm not in the group of folks who suffer the adverse effects of high ventricular pacing, and if it happens, there are effective ways to minimize those effects. Let me say the reassurance offered by Tracey, Gemita and others who also live with this go a very long way in making me feel better about it too. So I join Repero in thanking you all for the information and support. 

Risk Factors

by Penguin - 2023-09-08 09:24:15


Knowledge empowers us, prepares us and helps us consider our options.  Don't be afraid to ask questions about risks and what they might mean for you. That way you will be aware and more prepared and will be able to act more quickly and decisively if you are ever affected.  

All treatments have a risk / benefit profile. Pacing is no different. 

In your shoes I'd concentrate on how you will be monitored as Gemita suggests above and ask about this when you next see your EP.  I also agree that you should see v.pacing as a positive treatment for complete block. Where would you be without it?  

Best Wishes



by Penguin - 2023-09-08 09:36:16

Marybird, I have been in your position and watched my VP climb above the dreaded 40%, higher and higher. Unlike you I felt very unwell. 

This article is an interesting reflective piece about a study which dared to say that algorithms which deter VP may be ineffective at improving risk of heart failure etc.  I posted the article because it has a very useful table in it which suggests when VP is advantageous / disadvantageous. Repero will see that for 3rd degree AVB it's clearly advantageous.  It's an opinion based piece

The article dates back to 2017 and therefore some of it will be out of date.  For example, some years after this article was written my EP inferred that septal positioning hasn't panned out as hoped in his opinion. 

  There's clearly a lot of evidence that RVP can cause negative effects, in some cases, but exactly who may benefit from the avoidance of RV pacing seems to be less clear than I thought. 


I hope you find it useful.

Thanks again.

by Repero - 2023-09-08 12:22:23

Thanks again everyone, so helpful and supportive!

I'm going to Piggyback

by PacedNRunning - 2023-09-08 23:02:58

I'm probably going to repeat what others have said but wanted to chime in. I totally understand your concern about high RV pacing. I didn't start out with high RV pacing but my EP was very concerned with limiting RV pacing because of the detremental effects of long term RV pacing.  Of course me, I have to research for myself and see the data.  I do have heart block. Started  with high grade AV block. Needed V pacing but EP wanted to make sure I wasn't unnecessarily pacing.  I only needed intermittent pacing at implant.  Finding the right settings was tricky in the beginning becuase I started out underpaced.  I guess he tried to hard to only pace when needed.  Once settings were appropriate, I paced 50% of the time.  

The key with pacing for dual chamber is ON demand pacing. It only paces when the timer runs out for your heart work. They (tech) set the timer.  The timer should be based on your own natural timer. Meaning, they need to know the timing between your top and bottom chamber in order to tell the device how long to wait to allow your own heart to work before it determines it needs to pace you.  They can set the settings to beat your natural beats even though your own heart can do it. So they must tell the device to wait longer to allow your own heart a chance to beat.  I explain this because this is where unnecessary pacing comes into the picture.  Unnecessary pacing means your own heart can do it but the pacer is doing it for you.  Based on the research studies I read, most that were unnecessarily paced were those with SSS ( sick sinus syndrome). Those with SSS only need atrial pacing. They did not have AV block.  Device companies have sinced created algorithms to prevent unnecessary pacing. Ie MVP, VIP and rythmiq are some names from the device company.  Second, was those that developed Pacing Induced cardiomyopathy (PICM) already had low normal EF's prior to implantation.  Third, the studies revealed that those that developed PICM were paced unnecessarily.  My guess is because the heart was out of sync due to the pacer beating the natural heart. I really don't know they didn't say.  

I came here with the exact same question many years ago and Tracey E words really sealed the deal for me.  I've been counting down years since implant with each yearly echo I have.  So far after 5 years of pacing my EF is 63% . It did drop briefly to 53% but rose to 63% after 2 years.  My EP strongly advises me to get a yearly echo. He states practice guidelines don't recommend yearly echo's but he wants me to have them yearly.  I would agree with Penguin above about septal lead placememnt.  My EP said the exact same, I have a septal lead and my EP said the data shows not much difference between the Apex placement as far as risk for PICM. 

My take away after all my research and reading, is there is a fix if I ever develop PICM. An upgrade to a 3 lead CRT device. Knowing there is a fix worries me less because I know there is a fix to the issue if it ever happens. Lastly, I would want to know if I'm unnecessarily paced.  Great question to ask. Some only need intermittent pacing. I did in the beginning but after 18 mos, I paced 100% on demand.  I could feel my block getting worse. I say this because I know a gentlemen that received a pacemaker, his EF dropped to 45%.  He paced 100% of the time. Did his own research. Asked his EP to limit his pacing. Pacing went down to 1%. Fixed his low EF. His EF became normal after this.  I can't say how important it is to be involved with your heatlhcare especially with a PM. It's eye opening the number of people that don't get the attention they need with their device.  

Bottomline, those pacing 100% RV, there is a fix!!!!  CRT.  It is also a low risk. My EP actually told me, it's rare in his practice to see PICM.  I'm speaking from experience and my own research, talking to others, and asking my EP a million questions. :) 


by Repero - 2023-09-09 03:36:31

Thank you PacedNRunning for that super-helpful response.

I am not sure if my ventricles ever beat autonomously. I have a feeling that my Biotronik does play the waiting game that you describe after receiving an atrial pulse from the sinus node.- but not sure, will dive back into the technical manual.

The fact is, though, that prior to implant, I had bradycardia due to total block and a fixed heart rate of 45 bpm. So I cannot imagine that the ventricles ever respond naturally to a normally transmitted signal. Total HB is total HB I guess!

I am not getting yearly echoes. I will get my thoughts together and possibly contact my cardio department with a well honed clutch of questions. Thanks again.


by Penguin - 2023-09-09 15:31:56

Yes, thank you for that info PacedNRunning. You're a handy person to have around here!

Re: Unnecessary V.Pacing. - I did a fair bit of reading about unnecessary v.pacing a long time ago now. Most of the original research studies cited the DDD pacing mode as the cause of unnecessary v.pacing.  I understand that the VP reduction algorithms were designed because of this research - the so called AAI-DDD changeover algorithms, which keep a.pacing for SSS in the atria and only mode switch to DDD on strict criteria for v.pacing.  Very broadly speaking (don't ask me for too much detail) they use AV delays to achieve this. 

Here's the bit that bothers me - some of the AVDs used by these algorithms are pretty long, however these algorithms do not seem to trigger the problems you get with long AVDs / hystereses when using the DDD mode. E.g. PMT , RNRVAS, Cannon Waves, Pacemaker Syndrome - or at least that's my experience.  This bothers me.

The Abbott devices which I and Marybird have in situ, only offer a DDD pacing mode. They don't have the option of one of the AAI-DDD changeover settings (Rhythmiq, SafeR and MVP) that other manufacturers have and so do we need to be more vigilant about unnecessary VP - particularly if we have SSS? 

(Biotronik - Repero's device manufacturer also uses DDD which, as far as I know, is wholly appropriate for AVB.) 

Btw: I have PMd Repero to check that he is OK with these Q's on his thread.  He kindly confirmed that he was fine with it as the Q & A's may benefit others!  

Note: Edited.

Aaaaaccch, It's Greek to Me!!!!

by Marybird - 2023-09-09 23:46:24

Penguin, I very much appreciate your information and the article you linked in your response to my post. I've read it as well as other articles on studies addressing the nature of the adverse effects of high ventricular pacing. I'm still trying to absorb the material, but I get the impression the benefits vs. harm aspects of high ventricular pacing is still very much in debate ( like the debate about anticoagulation for people with "subclinical afib, ie, detected only occasionally for short runs on their intracardiac implanted reports and often as AHREs) and not entirely settled. It also seemed to me that heart failure as a result of dyssynchrony between the paced right ventricle and the left ventricle doesn't affect everyone who is paced ventrically, but possibly those who already have a lower ejection fraction or heart disease. Though they state around 20% of those with high ventricular pacing rates may develop heart failure, which of course merits close attention paid to the heart health of anyone with significant rates of ventricular pacing. AmIRite about that?

So I don't know where I am in all this mess. I got the in-office report last week about the 98% ventricular pacing ( 90% atrial pacing)- this after last year's adjustment to the VIP mode- I have had several remote monitor reports since that setting change but have no idea what the results were. The technicians both last year and this year explained the observed apparent heart block as the reason for the setting changes, and as I understand it this could be due to the progression of the sick sinus syndrome which affects not only the sinus node but also the AV node, hence the heart block. I can say when the tecnician turned off the pacemaker during the in-office check to determine my intrinsic heart rate, it was around 32 BPM. 

I feel just fine even with those changes, the lower heart rate on the pacer is set at 55, but it seems to hang out at 60 when I'm at rest not sleeping, and the rate response works well to get my heart rate to a decent rate for the activity I'm doing- up to a point,,I can't get it up past 110 as I exercise, no matter what. 

I have no doubt some of this high ventricular pacing/heart block is due in part,,at least to the medications I take to control my SVT, A-Fib and sometimes hard to control high blood pressure. This includes metoprolol, 150 mg/day and diltiazem ,currently 360 mg/day, but I'm cutting that back to 180 mg with my cardiologists' blessing to see if a lesser amount will still help with the breakthrough A-Fib and SVT I still get even with all the meds, and maybe cut back on the ventricular pacing.. I will discuss all this with the cardiologist and the pacemaker technician(s) see what the settings and numbers actually are, what they mean, and go from there. As I still feel just fine, I don't think it's an urgent matter, thank goodness. 

Anyway, I appreciate all your input, and it sure is an ongoing learning process. 

Repero and Marybird

by Gemita - 2023-09-10 05:46:56

Repero, your comments that everything is working well and that you were optimistic until you read about the risks of long term RV pacing is what is really at the heart of your post.  We all set out to allay your fears and I feel to some extent we have achieved this.

I remind myself, nothing has really changed for you.  You are “feeling” well without “symptoms” and that for me is an excellent sign that your current pacemaker settings are causing no real harm.  Most of us would notice a loss of synchrony if it were present.  Continue to learn, yes, but to change settings when there appears no need, would be highly unusual. Symptoms are what drives me to seek medical advice.  The only thing that has changed is your awareness of what could happen with a high percentage of RV pacing. 

Heart failure certainly doesn't happen to everyone with a high percentage burden of RV pacing (more than 40% is often quoted in research papers) and if it was going to happen it would likely happen early in our pacing journey when action (cardiac resynchronisation therapy) could quickly be taken to correct any ventricular dyssynchrony.  

Although learning about our settings, pacemaker and heart condition is clearly a good thing, I think it is important to keep this all into perspective.  There is really no urgency to change anything, to worry about anything in the absence of any adverse symptoms. Adverse symptoms would indicate a problem with pacing, with your heart condition or with another health condition when you would then need additional checks, not before.  Until that time I would live your life free from fear about what “could” happen since fear and anxious thoughts are certainly harmful emotions. 

In your shoes, I would want to ask a few important questions and when they are answered to your satisfaction, I would try to move on.  Also, if you are happy and confident in your team, I would let them know, since they need to know that you trust them.  You could perhaps ask:-

1. I have heard that for some of us, a high % of right ventricular pacing could cause ventricular dyssynchrony, possibly leading to heart failure symptoms.  With this in mind what checks will you be doing over my lifetime and how often, to ensure that any warning signs of pacing induced dyssynchrony are picked up early so that action can be quickly taken to correct the problem?

2. In view of the potential risks to some vulnerable patients with a heavy burden of RV pacing, could you please explain why a CRT pacemaker or a more physiological form of pacing was not mentioned or offered to me at the outset of my pacemaker journey?

3.  Although I have no current major symptoms to suggest that my current settings need adjusting, could you please confirm that my settings are all optimally set to help prevent pacing induced cardiomyopathy/ventricular dyssynchrony and could I please have a copy of these relevant settings

Marybird, You make some excellent points about your medication possibly changing your need for extra pacing in the RV and let us not forget in the presence of any arrhythmia our pacing requirements will change in any event, switching modes automatically whether we wish it or not.  I love AAI pacing which is so natural, but my goodness, switch me to another mode during a high atrial rate arrhythmia, and I am not the same person at all.  

I know for certain from my symptoms alone during RV pacing that I would be a future candidate for CRT and quickly too should I ever need a regular amount of RV pacing.  I loathe pacing in the RV.  The fact that you “feel okay” Marybird and you too Repero is an excellent sign that your pacing percentages/settings are right for you with your “present” heart condition.  Of course we all know that things can change in the future and this is why we need careful watching.  

We always say go by our symptoms, symptoms, symptoms and you won’t go wrong.  Why dig deeper if we don’t have too?   Our body is very good at warning us of a problem - most of the time!   Listen and trust it and learn to trust your doctors too, or seek another opinion.  If we have symptoms, then act, otherwise, perhaps we should all learn to leave well alone?  As you say Marybird, “As I still feel just fine, I don't think it's an urgent matter, thank goodness”.  That tells me you are doing well even with a heavy RV pacing % burden. There is often no right or wrong way to proceed.  We proceed according to our symptoms.

A fruitful thread

by Repero - 2023-09-10 06:55:37

Thank you Gemita, those are certainly relevant questions that I should pose.

You are also right to say that my fears have largely been allayed. It is all a question of perspective. I am content to enjoy the currently stable situation and to deal with any developments when and if they ever occur.

So this thread has proven very helpful for me and, I am glad to be able to say, for several others who have joined the conversation. I am pleased that it is proving so useful for everyone - please do keep the questions and answers coming!


by Penguin - 2023-09-10 10:38:37

''they state around 20% of those with high ventricular pacing rates may develop heart failure, which of course merits close attention paid to the heart health of anyone with significant rates of ventricular pacing. AmIRite about that?''

You will be better placed than me to answer that question if you are in the medical / pharmacology research field and used to looking into the results of meta analyses and the papers which preceed them! I think it would be more appropriate for me to ask you for your opinion considering your background and expertise which I respect.

As I am sure you will agree, research papers can be a minefield unless you really understand the factors and limitations that influenced the research results. That's why I was interested in an EPs interpretation of the results - hence posting an opinion piece which brings together years of research.  That's easier for a dummy like me to manage and I found it quite interesting, if only to challenge what I had previously been told.

I can offer you my own experiences with high burden v.pacing relative to the settings on my Abbott device.   However, I prefer to discuss anything personal and detailed off the open forum.  I hope you understand. If you would like to PM me please do so.  

With regard to this thread, despite Repero's kind offer for those of us with SSS to continue posting, I personally don't feel it's fair and won't post further. IMO it's more helpful to hear your own personal risk factors directly from your EP as they will know which risks apply to you. 

Best Wishes (Edited) 

Agree with Gemita

by PacedNRunning - 2023-09-11 01:27:13

I use the same motto for myself. No symptoms and everything is good. Our body has symptoms to warn us if something is out of balance. Our body works very hard to keep us balanced. So when something is off, we will know. The one thing with PICM is it can come up with no symptoms. The RV pacing can cause the LV to enlarge over time. Regular echos can pick it up early. So those are important to ask what your team recommends. The interesting thing about settings in my experience is if things feel good, don't mess with them. :).  I want to note I was not inferring anyone to change settings. I was giving an example of someone who was proactive and asked about settings and surprisingly had some interesting results. When he explained his story, I complimented his medical team for trying this out. He corrected me and said it was his idea. Shocked me even more. It was just surprising to me because I only got really involved with device settings etc because they had a such difficult time adjusting my settings that I felt I wanted to learn and help. It was only because they kept saying " we aren't use to young active people."  Otherwise, I was staying in my lane. :). 


by Gemita - 2023-09-11 02:58:51

And I certainly wasn’t inferring that you or anyone wanting to take an interest in their settings was in the wrong.  It is certainly important to be interested in our own health care and that includes learning about our pacemakers and settings.  I find your posts truly inspiring PacedNRunning.  You have the ability to turn a technical subject into a good read and your posts have certainly opened my eyes to what might be possible, so please keep them coming.

35 or so years

by dwelch - 2023-09-19 01:40:09

Im on device number 5, 35 or 36 years of pacing, have to do the math.  My EF was not great to start, but over the years it dipped from the 40s into the 30s.  For about a decade, probably second decade of having pacers.  actually more than that, number five is a biventrical put in to deal with up to then what 30 years of RV pacing.  My EF dipped down into the 30s (again an echo every year for a long time, your doc should start doing that I dont know,15 or so years in).  So number four's life was cut short to put a biventrical in.  At first my understanding it would stop it but instead it is the higest it has ever been.   It was a long year from implant to findingout if the new pacer helped or if it was not bsaed on decades of pacing.  The doc moved, the old place I could do an echo just before the checkup,  not at the new place so had to wait another 6 month interrogation cycle to get an echo...

I did not read all the posts but Tracey had a good point which is THE point, better to be paced that not. 

I dont think RV pacing is some overnight death thing, unless your doc is not paying attention.  Not sure how many years in you are.  device two or three IMO should start doing echos if not sooner.  just ask the doc their opinion, they are the doc not us/me (Although Tracey's knowledge is...)

Complete block like you, me and others here.   We are 100% paced, does not mean 100% dependent, but in any case if you look into what complete block is and looks like on an ekg, pacer needs to fix almost every cycle.  

Thank you dwelch

by Repero - 2023-09-19 04:52:51

Thanks for that perspective. Helpful.

I have only recently received this, my first, pacemaker. I am already pretty old so it may just be that I'll never need a second one. By the same token I may also avoid long-term RV pacing problems by the simple expedient of absenting myself before it happens.

"Better to be paced than not! - quite agree. My quality of life has been restored by my PM and I plan on making the most of it!

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At age 20, I will be getting a pacemaker in few weeks along with an SA node ablation. This opportunity may change a five year prognosis into a normal life span! I look forward to being a little old lady with a wicked cane!