After being unwell for a while with irregular heart rhythms, high heart rate and BP (see my previous post), I had a three month check up yesterday and I thought I'd share it with you.

My first question was had I had any AF or arrhythmia since last time as I can feel an irregular pulse when when my HR rises to 90 to 102. I was told I had not been in AF and not had arrhythmia.

I asked about Rate Response. I was told the setting was what I needed but when I explained how my heart rate doesn't drop after activity, it was agreed that the Recovery Rate was changed from standard to fast.

I asked about high atrial or ventricular heart rate episodes which may require pacing therapies but the system showed no signs of any such issues.

I am set at 55bpm, is this too low for me? I was told that this is fine and 60 would make very little difference.

I get irregular rhythms which I am told are ectopic beats. The system showed less than 1% of ectopic beats and was told that this is fine.

My LV lead is switched off. I asked if this should be turned on. I was told it was not needed at present as the LV is working well.

My % pacing is 98% atria and 8% RV.

The only issue was a fluctuating voltage on the LV lead. I was told it isn't damaged or in the wrong position but it may have moved. I had two chest X-rays and the consultants will discuss this in their meeting next week. They will also discuss my need for an ablation.

As I have been so unwell, I find all the positive findings a bit confusing. I will get my second blood test results next week and that might highlight something.

Thanks for reading this.



Lots of good information Graham

by Gemita - 2023-12-15 12:27:24

Thank you for the update Graham.  I agree completely with you that your symptoms do not in any way match the glowing results that have come from your data.  We always say here that it is how we feel that counts, not those numbers/data.  I would like to go through your list of answers received and offer perhaps an explanation where one may not have been adequately provided by your doctors?

You say you feel an irregular pulse but that no arrhythmia was seen or recorded and certainly no Atrial Fibrillation when your HR increased 90 to 102 bpm.  This may have been caused by ectopic beats, or by slow AF since AF can occur at a slow, normal or a fast speed.

Your EP will set your detection rate for high rate atrial or ventricular arrhythmias appropriately for you with a defibrillator but it would certainly be higher than 90-102 bpm, otherwise you might get too many inappropriate shocks.  

For atrial tachy arrhythymias, they usually set it in the range >170 bpm and often higher;  for ventricular arrhythmias in the range >150 bpm or higher, so clearly if you do not exceed/reach these rates, no high atrial or high ventricular arrhythmia episode will be recorded which may give a false sense of well being as I have often discovered and so have many other members.   So to sum up if an arrhythmia occurs at a slower rate than the parameter set by your doctors for its storage and reporting, it may well be ignored and certainly would not be stored on your device’s internal electrogram or reported in your arrhythmia logs.

I am very glad you have got your Rate Response adjusted to drop more quickly after any activity and I hope you will feel more comfortable.  That is an achievement to have negotiated this, so well done.

I beg to differ about your lower rate limit of 55 bpm being okay.  If 60 bpm would make very little difference according to your doctors, then why not raise to 60 bpm since anything lower than 60 bpm is regarded as bradycardia.  You sound as though you need all the help you can get and in any event 60 bpm will be better for your ectopic beats which might be triggered by any slowing, pausing beats.  1% of ectopic beats might sound minimal but in practice they may still be bothering you.

I still cannot get my head around why the LV lead is not switched on for optimum pacing.  Why bother to implant a CRT system if it is not fully utilised.  The LV might be working well at the moment, but why wait for dyssynchrony symptoms to occur before resynchronization therapy is utilised?  I note you are mainly pacing in the right atrium (like me) which should feel very natural and that you are pacing only 8% in the RV, so this is perhaps why they say you don’t need the LV lead switched on since 8% RV pacing should not adversely affect your LV.  However, you may not feel that comfortable when being paced in the RV and it may not be helping your ectopic beats either.

It seems they are watching the fluctuating voltage on the LV lead since they say the lead may have moved. I am glad you have had chest X-rays and the consultants will be keeping an eye on this in case you need to utilise the LV lead in the future. 

On the need for an ablation, this rather confirms my point above, why would they consider your need for an ablation if you are having no arrhythmias?  It seems to me that you are having "symptomatic" arrhythmias but perhaps at slow heart rates which is why they are talking about an ablation.  I see your Bio confirms a number of arrhythmias and current Amiodarone therapy.

Of course you find the positive findings confusing when you continue to feel so unwell.  I do hope they can throw some light on what might be causing your symptoms, but don’t rule out slower arrhythmia episodes like Atrial Fibrillation or other slower heart rhythm disturbances that might be present that do not meet the criteria set up for their recording and storage.  You certainly wouldn’t have cancelled your trip to Thailand if you hadn’t been feeling so unwell.  I hope for the very best Graham.


by Penguin - 2023-12-15 15:15:47

Hi Graham, 

I don't have a CRT device, nor do I have any information for the device that you have.  However, I would offer this information which applies to pacemakers: 

  Pacemakers can be programmed with a variety of alerts and episode triggers. These usually trigger ECG storage of the 'episode'.

This means that when your device is interrogated in the pacing clinic any alerts and episode triggers show up on the technician's screen and the technicians can then tap into them to view the ECGs. 

Sometimes no alerts are triggered and if you have been symptomatic this may be because your particular arrhythmia do not meet the alert triggers and episode criteria programmed. 

 Therefore, in your shoes, I would ask about the alerts and episode triggers that are programmed and consider or discuss with your techs / EP whether or not the criteria are appropriate or not. 

Sometimes, as Gemita says above, it simply isn't possible to programme an alert or episode trigger for arrhythmia at lower heart rates because the pacemaker has limitations regarding what it can and can't recognise. Low rate episodes seem to be particularly problematic. 

It may be worth discussing your test results pre-CRT (if you have them) with your EP / Technicians as these should give some idea of the rates at which your arrhythmia occur.  

Also ask whether or not there are any reasons why your CRT cannot record the arrhythmia you feel.  

PVCs can also trigger alerts and these are programmable too.  It depends on your device but there are options for alerts / episode triggers which include consecutive PVCs - which you may feel more than single PVCs.   It's also possible on my device to programme alerts for VT which is due to atrial arrhythmia. 

Again, I repeat that I don't know the programming options on your device - but it may be worth asking some questions if your episodes are unclear and you are frustrated by no evidence or explanation. 

Best Wishes 


by Lavender - 2023-12-15 20:22:21

It's so difficult, and happens a lot it seems, that we feel unwell and are told all is well. 🙄

I would say that the majority of us are set at a low of 60 bpm. If someone turned my rate down, I really think that I would be tired. 

Maybe the bloodwork will turn up some clues like low iron?  I have no idea but I would continue to seek answers until you do feel better. 
God bless you. ❤️💚

My thoughts

by Graham Harry - 2023-12-16 06:21:47

Thanks for your comments. One of the reasons they didn't change the setting to 60 was, after a discussion between the two techs, they thought it best to only make one change this visit and they had already changed rate response. 
As for not picking up any arrhythmias at lower heart rates, I was under the impression that the system records all rhythms from 55 upwards. Maybe it does but they only checked above a set level which is above the rate where my problems occur. 
I will see what the blood tests bring and the cardiologist meeting on Thursday. In the meantime, with the help of your recent very helpful comments, I am writing a letter to all my doctors. Thanks again.


by Penguin - 2023-12-16 07:33:15

Hi again, 

It can make sense to only make one change per visit.  Lots of clinics do this. It's so that they can see the effect of that particular change.  No effect = try something else.  Good effect = likely that this was the problem.  Makes the trouble shooting easier. 

I was under the impression that the system records all rhythms from 55 upwards. Maybe it does but they only checked above a set level which is above the rate where my problems occur. 

Again, I stress that I don't have a CRT, nor am I familiar with your particular model.  Most devices don't have the storage capacity to record and generate a report for all rhythms. They record those that they are programmed to record and these 'alerts' 'events' 'episodes' are the ones that the technicians look into and keep on file when they interrogate your device. 

The alternative ways to trace a problem symptom other than via alerts are

a) keep a note of the date and time at which it occurs so that the clinic can look up the ECG recording for that date / time if it is accessible. 

b) ring the clinic when the symptoms are happening so that they can look at the information generated by a home monitor download.  

In the UK we are not routinely provided with manuals for our pacemakers / devices, but Abbott's website will allow you to obtain one.  Customer services in the US will provide one to you if you email them. A list of the alerts / episode triggers that can be programmed is usually listed in the manual. 

Warning: the manuals can be lengthy and technical.   

It may be best to check the manual first or check with your technicians (who sound helpful) to be sure that you are asking for settings that your device offers. I can only speak for my own Abbott pacemaker and my own understanding of how alerts are programmed. 

Best Wishes


Let us not overlook the bigger picture either

by Gemita - 2023-12-16 10:01:53

Graham, despite everything that has already been said, we mustn't perhaps overlook the bigger picture that you do have a diagnosis of Hypertropic cardiomyopathy with myosin protein C mutation; a history of poorly tolerated AF and other arrhythmias.  In addition, you are also taking a powerful anti arrhythmic medication "Amiodarone" for non sustained VT as well as a number of other meds.   The Amiodarone can adversely affect your thyroid and other organs which is probably why they are checking your bloods.  

I see you have a host of other diagnoses found by the Reveal Linq implant monitor, so clearly you have a history of heart rhythm/rate disturbances and syncope and I therefore do not think it is unreasonable for you to be asking for further clarification about what can and cannot be seen on your CRT-D data downloads?  Just to confirm this point I recently asked my clinic to explain how my % time spent in AF is calculated?  I was told it only includes episodes that meet the detection rate set for an atrial arrhythmia (over 170 bpm), so if I had episodes below this detection rate, say at 150 bpm, these episodes would not be collected or included in the % time in AF figure.  This clearly is misleading and does not represent my true AF burden, does it, since as already mentioned, AF can come in at exceedingly slow rates, 30-40 bpm, normal rates 60-100 bpm and higher rates well above 100 bpm.

I was also told they use holter monitoring to collect more detailed info in patients with devices, so it is clear from my discussion with my clinic and from what I hear from other members, that data collected and/or stored on our device is based on what your doctors have set up and want to see.  It is not based on every single heart rhythm/heart rate disturbance we might be getting.  Of course they may feel that any lower rate arrhythmia episodes, especially atrial ones, are relatively benign, while ventricular ones like non sustained VT need watching.  I hope this helps with any letter you might decide to write.

Take it easy Graham and recover well

Another update

by Graham Harry - 2023-12-21 14:27:00

After contacting the cardiac department, I got two phone calls this morning from two different cardio techs re my ICD. Long story short, there has not been any AF, tachycardia or arrhythmia and the CRT-D does actually record all such activities from the 55bpm setting to max levels not just the high rates so yes it is sensitive enough. This was reassuring. I was told the rate response would not cause the high heart rates whilst at rest. They said that would be ectopic beats and recommended a higher level of beta blockers. I can visit the hospital next week to have the rate response turned off it I want (I said I'm not the expert, I will take your advise). We agreed to see how it goes over Christmas.

The bad news is the RV lead (not LV) seems to have moved and is using too much battery power. This won't affect me in the short term but I will have to have the lead replaced at some stage. This could involve open heart surgery!
The blood tests were okay but I have to have liver tests again in three months time. The amiodarone may be affecting the liver.

No news of an ablation. It seems that due to having had no tachycardia etc that I might not need one but I would like to get off the amiodarone.

I must say the guys at Royal Cornwall Hospital were very informative and said I could pop in next week to make some adjustments if necessary, he would even take the call from home. We were on the phone for over half an hour.

Merry Christmas to all of you, stay well and enjoy yourselves. 

Thank you Graham

by Gemita - 2023-12-21 15:51:31

for the update. That is reassuring that they are recording all your irregular arrhythmias at whatever speed.  Perhaps this is because you have a defibrillator and they need to know this level of detail.  You will have a bigger device than a simple pacemaker, so more storage space.  

I suspected and suggested that the higher heart rates could be due to ectopics coming in fast.  I was told this about mine which surprised me at first, since I always thought ectopics were slow and pausing, so it was interesting to learn that they can come in fast.  Afterall, premature atrial contractions are often triggers for atrial fibrillation and premature ventricular contractions are often triggers for non sustained VT.

I found my Rate Response triggered more in the way of ectopics and bursts of tachycardia, so eventually had it turned off, but test it over Christmas.

What a shame about your lead.  That was very unlucky, although CRT devices can be tricky to implant.  It is usually the left ventricle lead though that causes problems, not the right.

The Amiodarone is clearly holding off your arrhythmias.  I wonder what would happen if you tried to come off it.  I can imagine with a defibrillator you will want to keep an arrhythmia like AF firmly under control, even though the defibrillator shouldn't shock you for AF, but only for a serious sustained ventricular arrhythmia.  

Your cardiac team sound truly caring Graham and I feel you are in good hands.  I wish you and the family a wonderful Christmas too and hope you will make good progress.  I shall be preparing home made Ravioli on Christmas Day (spinach and ricotta filling).  My Italian husband loves his pasta with a home made meat sauce.  

Check up

by Graham Harry - 2023-12-30 07:20:47

I had my CRT-D checked again yesterday. All the readings were good and there was no recordings of AF or arrhythmias. I asked again about the setting of 55bpm and was told that these days 50 to 55 is the accepted setting as modern thinking is that 60 is too high as there is less range when the rate needs to increase.

The rate response was changed back to medium and we will see how this goes. Ironically I have been really well these last three days, typical that I was feeling well on check up day!

I am 55bpm 80% of the time and there were a few high peaks or 120-130 but they weren't concerned as this could have been whilst I was active. The good news is the RV lead was giving a steady reading so they will keep a check on that. In the meantime they recommend that I speak to the consultant who fitted the ICD and discuss ablation, meds and other options. 

Thank you for the update

by Gemita - 2023-12-30 08:45:01

Graham, your updates will not be seen, unless you do a new post.  I am able to see them because I have Admin privileges and see a daily list of all "comments" to posts.

Perhaps you will become a super responder to pacing like me and your arrhythmias might be helped as well.  We are all different and as long as you feel well with 55 bpm lower rate setting, then that is all that matters.  

At 55 bpm my premature beats would be over active and these would frequently lead to AF, so I will most definitely not go there.  Also a normal heart rate is anything from 60 bpm to 100 bpm, so 50-55 bpm would be classified as bradycardia, with anything over 100 bpm classified as tachycardia.  

Of course no one wants to be pacing at close to 100 bpm night and day, but there is plenty of room for rate increases up to a maximum of 100 bpm(!), so 60 bpm is certainly not too high according to my doctors.  But I agree, they prefer our hearts to do the work and not to get lazy, but if we don't feel well on the lower settings, we need to speak up.

I am paced at 70 bpm and at this rate my pacemaker is overdrive pacing many of my slower, pausing beats with great success and preventing AF from being triggered.  I may use up a little more battery but if I feel better, it is certainly worth it.

So pleased you are feeling better Graham and your arrhythmias are well controlled.  Perhaps you don't need anything more done?


by Graham Harry - 2023-12-30 08:52:46

for the reply and the explanation of add comment/new post. I have a message to call my GP next week and I will post again if things change. A happy New Year to you.

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