Symptomatic when paced

I can empathise

by crustyg - 2024-08-30 10:11:48

5years in, SS+CI, but over the last nine months I have increasing episodes of AV-block.  My EP-doc and I are still discussing the cause (very high vagal tone may be one factor), so we've enabled my RV (apical) lead.  My PM has a useful mode where I'm paced AAIR, but if AV block develops it starts pacing RV as well (DDIR), and after a configurable time, if AV conduction has become normal again it switches back to AAIR. I could really feel the onset of RV-pacing - felt like a small kick in the chest, and if I'm out on my bike, it's my *impression* that my cardiac output is lower than RA-only pacing for any given HR.  IIRC, RV-apical pacing can produce functional mitral regurgitation (as the activation impulse would normally reach the papillary muscles which close the mitral valve before the bulk of LV contraction starts).

We reduced the activation output for my RV lead (was much higher voltage than RA) by doubling the pulse width, and it's definitely made RV pacing less uncomfortable.

Your device *may* have a similar mode that spares RV pacing as much as possible.  If your device can't handle this, then either you need a different EP-doc (I'm on my fifth) or a different PM - or both.

I feel your discomfort too

by Gemita - 2024-08-30 14:37:25

Xtrabeat, I wonder if there would be any benefit in asking to see another technician/EP in the same hospital for a second opinion?  I did this in my London Hospital and never regretted doing so.  Just to have someone prepared to really listen and to go the extra mile to help us to understand what might be happening, is so important to our healing and acceptance of our heart condition. 

As you may know, I too have numerous documented arrhythmias with some right bundle branch block, aberrant and retrograde conduction sometimes seen.  What I always ask myself is, is it my own heart dropping the beats causing my symptoms as my heart rate decreases/increases, or is it my pacemaker not filling in the beats in a timely manner?   I suggest it might be a bit of both.  

From my symptoms it feels as though PACs and PVCs are a strong trigger for many of my rhythm disturbances.  PACs and PVCs also appear to cause timing issues for my pacemaker, often delaying both atrial and ventricular pacing.  To make matters worse, the pacemaker apparently correctly senses these ineffective ectopic beats and withholds pacing when I am at my most symptomatic.  During frequent ectopics this can leave me feeling extremely weak and at times unstable.   Clearly the effective output from frequent ectopic beats or during an irregular rhythm disturbance like Atrial Fibrillation will be significantly less than from a normal heart beat.  Like you, I can become extremely symptomatic especially if I try to exert myself during any high heart rates.  

I am really only comfortable when AAI paced and when in normal sinus rhythm.  The moment I switch to DDI mode and the pacemaker controls pacing, my symptoms can worsen quickly.  During an arrhythmia either pacing induced or caused by our heart’s own electrical disturbances, getting our settings adjusted to meet our individual needs requires real patience and determination.  It will not be an easy fix. 

Like Crustyg I am very sensitive to RV pacing and know instantly when this happens and yes I feel too that my cardiac output is lower when pacing in the RV, no doubt due mainly to my rhythm disturbances during RV pacing.  For example, I know that I lose good atrial support (known as the atrial kick) during Atrial Fibrillation episodes which may contribute up to 35% of my cardiac output.  This loss is not insignificant, so perhaps this is one of the reasons too why I am so symptomatic during these periods.  

Why blame the pacemaker?

by Selwyn - 2024-08-30 16:03:39

Hi,

I see you are a 1948 vintage. You certainly should be able to tolerate heart rates above 120 beats per minute without feeling faint. The fact that you feel faint at higher heart rates suggests that your cardiac output is reduced at a faster rate.

The next question is to ask why? I think this should be answered by your cardiologist. Not everything in life relates to being paced.

What would happen, if for the sake of arguement, you had coronary artery disease that could not supply your heart muscle with the required oxygen level. Yes, some people get angina pain, others don't. Coronary artery disease may be silent ( Mine was with a 90% narrowing of the main coronary artery).

I suggest you ask your doctor for an answer about your symptoms and don't be put off by blinkered thinking.   Personally, I would want some further investigation.  Indeed, for me it was live saving to have a coronary artery stent.

Exertional V pacing

by Rch - 2024-08-30 22:28:19

Hi

I experience very similar episodes on exertion as you do except that my symptoms are not that severe. I have a Boston Scientific accolade in DDD mode implanted in 2022 for exercise induced Mobitz type 2 ( 2:1). As of late however, while on treadmill or walking up couple of flights of stairs, when my HR picks up and exceeds 110-120 or so ( my MTR 130), I begin to feel the V pacing without any signifiant symptoms other than thuds in my chest. So I do stop and then check the rhythm on Kardia and my BP which would be about 150/85 ( baseline 120s/70s). The V pacing will continue for a few minutes even as my heart rate falls below 100, and then eventually gets reset to my baseline ApVs after a few minutes. While I do believe it might be some sort of a progression of my AV block, my Cardiologist feels there might be some element of CI that might be triggering the V pacing. So, I will be seeing him in a few days to program to DDDR! 

 I have had a negative myocardial perfusion scan 2 years ago and an essentially normal echo and EF. As Selwyn suggested if you have not had any w/u to exclude myocardial ischemia while the pm was implanted, you might want to discuss your symptoms with your Cardiologist. Myocardial ischemia has to be ruled out in any new onset heart blocks. One of the other causes of exertional dyspnea and fatigue in people aged 70-80s like us, is heart failure with preserved EF, which in fact is more common than ischemic heart disease. I’m not implying that you have it but I think it wouldn’t be a bad idea to discuss your symptoms with your Cardiologist to consider alternate causes of your symptoms other than just the the pacemaker. I wish you well, and keep posting on your progress.

(P.S. I personally have other issues with my pacemaker but it would be a different discussion for another day!)

To Crustyg

by Rch - 2024-08-30 23:02:07

Crustyg

Hi

I see in your bio that you have B S Accolade. I’m just wondering if your present settings are AAIR with VVI back up which is RYTHMIQ with AV search + in the Boston Scientific Accolade.  I have read this mode is generally used to minimize V pacing in people with reasonably good AV conduction! 

Difficult to know how best to advise

by Gemita - 2024-08-31 01:11:40

Xtrabeat, after reading Selwyn and Rch's additional helpful comments it is indeed difficult to know what to advise.  I just found a comment from you in one of your earlier threads to say: "I had normal coronary angiogram in 2017 but a recent CT coronary angiogram has shown some narrowing in the distal circumflex with a dominant right artery and normal left. I am now taking a statin. I don't think any further action about this is proposed".  Perhaps with respect you should ask whether there has been any further progression since your CT coronary angiogram causing your current symptoms?  I would specifically want to know the degree of narrowing and whether this needs treating now or in the near future or whether they intend to manage with medication alone? 

However, in the absence of any significant blockage or other structural cause for your symptoms, like a leaky valve, my feeling is that your own heart rhythm disturbances are likely progressing or changing which is what electrical disturbances tend to do, making pacing adjustments particularly difficult to manage during volatile periods.  Additionally your doctors don't seem to be particularly concerned if I am reading the room correctly, which doesn't seem to point to a serious condition at this time?   I hope therefore that you will find the best pacing and rhythm/rate control solution quickly to ease your symptoms whatever the cause.

My personal advice is not to go rushing in with a sledgehammer to fix a relatively benign condition, if indeed it is largely benign, and to work tirelessly and patiently with a team that you can have complete confidence in.  You have still some way to go perhaps in this respect.

Thanks everyone

by Xtrabeat - 2024-08-31 07:49:52

Thank you very much for your helpful comments. I think my best plan of action is to get a further assessment by a different EP. 

Gemita the CT angio was in May this year and was said to be soft stenosis of the fairly distal part of the circumflex. There is good run off and the expectation is that it will improve with statins - although I am not that happy about taking them as my LDL was nevr that high and now on a small dose of Atorvastatin is down to 1.3 mmol/L after only 6 weeks (previosly 2.1 last year and 2.7 this). Cholesterol isn't all bad is it so what is happening to hormone production etc? I have also been pretty aggressively managing diet and have joined Zoe - but that is another story.

I also had a treadmill test which was negative except it showed my rate did not rise as expected - got stuck at less than 120 bpm - previously I had been quite comfortable at 160 so this is a major change for me - and the limit to my activity.

My current programming is quite complicated because i am prone to PMT - was woken up last night with a pulse of 120 and PM firing - I am not sure what triggered this. I am not having so many ectopics now,. The cardiologists haven't been over-concerned about this and one emphasised that I should resist any attempt to intervene with the narrowing of the circumflex saying it wasn't worth the risk and that at worst it might lead to a "minor!!" infarct!  The bottom line is that this may be the best I can get - but it is a major disappointment .........

I really value your input - I had better do some reading as I don't really understand all the possible pacemaker funtions and what my PM can do!