Odd revelation today

I've been having occaisional, minor, chest pain between the five and fifteen minute mark of my daily walk. I'm fine for the rest of the time.  I've checked my pulse at times and it's varied between 110 and 140bpm, maybe a bit more but never believed it.  My max is 130, it can't be above that.  Right?

Today, I found a chart of rate on my watch (I know, it's unreliable) but exactly when the problem occurs, the chart showed a large bump in the HR, exactly between that 5-15min mark, then goes back down to 110-115 for the other three-ish hours.

I already had an in-office PM check appointment for Wednesday so I'll ask her what's going on.  I suspected that it was related to RR but thought it just the opposite (RR not ramping or sticking properly). It seems that it's overshooting.


Heat, dehydration

by Persephone - 2022-07-24 18:39:34

I'm going to continue my relentless questioning if heat could be related. You can tell me to "go to grass" as my Philly friends would say - but a possibility?


by islandgirl - 2022-07-24 19:28:43

I don't know very much, but have a question regarding your max heart rate--and wondering about it for myself, too.  Isn't 130 the rate the PM will increase to, and if it goes higher, it's your heart bringing increasing on its own?

I've also found my showing a high pulse when I feel a fast rhythm. I will take a photo of my iwatch face and show it to the EP when I see the EP.  

Good luck and stay well!



What she said

by Lavender - 2022-07-24 19:45:18

I too thought that the heart can go above the max rate and the pacemaker just lets it go on its own without interacting. (?)

In any case, AgentX86, ala Maxwell Smart, we are counting on you to get to the bottom of this case and report back here with your findings. We count on you to learn and then teach! 🤜🏻🤛🏻

As for ...I've been having occasional, minor, chest pain between the five and fifteen minute mark of my daily walk...sorry about that, chief! Hope your pacemaker tech can explain. 

Max rate

by AgentX86 - 2022-07-24 22:01:34

In most cases, you all would be on the right track, I think.  However, my max rate is the max rate.  I have had an AV ablation so my atrium aren't connected to the ventricals at all, so the SI node doesn't do anything either.  My heart is completely regulated by the pacemaker and its RR.  BP is still controlled by the sympathetic nervous system but rate is controlled by the PM. I don't quite understand how adrenaline or other fight/flight hormones would figure into it.

Otherwise heat and dehydration could do anything but, also, this is in a temperature controlled gym. It happens outside, too, but I don't do any distance when it's above 80F.

I haven't told this story before but AgentX86 is a play on both Maxwell Smart and Intel processors (Smart = Agent-86 and the Intel 8086 descendents, known in the industry as X86 processors.  About 20-25 years ago, I was invited to an Intel executive meeting during an Intel conference, even though I worked for a competetor (another division was a customer). When I got back from the conference the guys came up with the name "AgentX86". A double meaning of Agent (spy) and X86 and also Maxwel Smart. Since I can never come up with a decent nym myself (no originality), I just use it. 🕵️‍♂️

The story

by Lavender - 2022-07-24 23:02:51

Ahhh thanks for the story of your nym! I like it-it suits your elec-engineer background and tech savvy ways🥸

I'm always learning from you.👀

Spiking heart rates

by Gemita - 2022-07-25 07:38:43

Hello AgentX86,

I am sorry to hear of your occasional, minor chest pain during the early stages of your daily walk, since I know how much you enjoy walking.   The fact that you are having chest pain during brief periods of sudden higher heart rates, tells me that your heart is occasionally being pushed above a safe limit for you and this needs correction once the cause is identified.  But what is the cause?  

Can we really say, I wonder, that your heart rate is completely regulated by your pacemaker and its RR?  I am not always so sure.  I appreciate an AV Node ablation has been performed (which rarely fails) which will not allow any atrial tachy arrhythmias to pass through your AV Node to push your ventricles too fast, but what about the possibility of a run of ventricular ectopics triggering some non sustained VT as you start walking?  Could that be a possibility I wonder?  Perhaps they could increase your base rate to try to overcome any ectopic triggers and see if this might help?  Cannot remember what your base rate is permanently set at?  I think it might already be set fairly high at 80 bpm?

A couple of other thoughts:

Unlikely(!) I appreciate, but it can rarely happen.  Is your AV Node ablation breaking down and allowing any atrial tachycardia signals to get through your AV Node to affect your ventricles?  When you go back on Wednesday for a review, no doubt they will look for any “Events” (like VT) as a cause for your occasional spikes in heart rate and I believe they will be able to differentiate any "Events" from being caused by Rate Response (RR) or initial exertion on walking.

RR problem?   As you know, I have only just had RR turned on so cannot offer personal experience with this setting.  I go back in early October for some checks and adjustments.  My technician did say that if I noticed worsening arrhythmias, to let them know.  My arrhythmias have increased since switching on RR but of course we have just had a rare heatwave in the UK and I really struggled to sleep for days, so I cannot with any confidence blame the increase in arrhythmias solely on RR.  

It sounds to me to be more arrhythmia related, possibly caused by a change in your heart condition, or triggered by a pacemaker setting or another health condition?  I hope you will get some answers on Wednesday AgentX86 and please report back.  

I hesitate to post this...

by crustyg - 2022-07-25 07:43:46

...since it seems too simple/obvious - so it's probably *me* that's missing something. But here goes anyway.

Agent: why can't this be a burst of VT?  Your PM isn't going to be the rate limiting factor if this is what's happening, and it's certainly possible to trigger a tachyarrhythmia under some circumstances.  For me, it's atrial tachy (on the couple of occasions when my PM has logged it), but it could as easily be ventricular.

A large sympathetic drive can make the heart muscle more sensitive, and a low potassium (and/or low magnesium) would make it worse.  But it doesn't have to be near the end of an exercise period - I used to notice tachy-episodes within 500m of setting off for a run on some days, and then my HR would settle down for the remainder.


by Gemita - 2022-07-25 07:47:59

Sorry, I just beat you to it with the same thought on possibility of VT.  Apologies


by Tracey_E - 2022-07-25 09:31:58

Just because it's been ablated doesn't mean paths can't come back. 

If I were you, Agent .........

by IAN MC - 2022-07-25 11:27:04

I would ask for a PM interrogation while you walk on a treadmill . If you can guarantee to produce the symptoms they should be able to come up with a definitive diagnosis,

Best of luck



by Gemita - 2022-07-25 11:51:50

AgentX86, I believe you haven't long recovered from Covid.  I would consider this also to be a potential cause for any worsening symptoms.  I remember when I had Covid, my cardiologist/EP was not at all surprised that I was experiencing additional arrhythmias with chest discomfort

Revelation - followup

by AgentX86 - 2022-07-25 22:35:00

I don't think it's V-tach.  It's rather slow for VT (it appears to be in the 140s) and it's always near the beginning of my walk, never elsewhere, and resolves in the same time each time. Potassium is a real possibility.  I take 400mg of magnesium a day (100% RDA), so I wouldn't expect that. I wouldn't think that it would be regular and resolve the same time each time.

A ten minute V-tach episode would be worrying indeed.

This has been happening for some time but it hasn't really bothered me.  More of a tighness than a real pain.  It doesn't slow me down, either. I can rule out covid because it predates that, though I only recently discovered a correlation with HR.

I had a remote transmission in June and didn't hear anything.  As I said, I'm going in Wednesday morning for an on-site interrogation, an appointment made six months ago at my last on-site. I'm trying to get it to coincide with the time changes but so far haven't put the pressure on to do it.

I've never heard of an AV/His ablation failing but there are other pathways that can form.  Haven't seen it discussed as being after an ablation.  I have seen it as a failure that acts in a similar way as PMT). If it were a failed AV abation, I'd see the permanent flutter come screaming through at some point.

It's interesting and any of the above is possible but the regularity makes me think something amiss with my pacemaker.  Most likely some screwy RR settings allowing it to overshoot before correcting.  There isn't enough information yet but I'll add anything I find Wednesday (if anything).  I see my cardiologist the 10th so I'll bring it up then too (it won't make my wife happy). My EP fired me unless I have further problems.  Not there yet, I don't think.


Hope You Solve the Mystery

by SeenBetterDays - 2022-07-26 09:32:01

Hi AgentX86

Sorry to hear you've been having some issues.  I love my walking too so know that you wouldn't want anything to spoil your enjoyment of that.  It's strange how it happens at the same point each time.  Does it correlate with any part of your walk?  I know my heart can jump up pretty quickly if I ascend a hill (even a short one!).  Is there anything at that point in your walk which might make your heart work harder.  I know that you said that you do your walking in the gym if it's warm so do you walk on an incline at all?  The timing seems significant so you are most likely right that it may well relate to your rate response settings.  Hope you find some helpful information at your appointment.  I always find your contributions on this site really insightful and informative so a big thank you for that.  Let us know how you get on.

Best wishes


I missed the 10min duration

by crustyg - 2022-07-26 11:26:23

Good point Agent.  It's there in the OP but I hadn't worked out a 10min duration.  Yes, 10min of VT at 140 seems extremely unlikely.

New pathways: my first 'Extensive ablation' for classical CTI AFlut lasted about 6months and I was back in it, same classical pattern.  I suppose we should be grateful that our hearts can do more than just form scar tissue.

Is it enough of a concern that you'd push for a Linq Reveal implantation?  In your shoes I'd be concerned about that chest tightness: IMHO that's your myocardium complaining about lack of blood supply until proven otherwise.


by AgentX86 - 2022-07-26 13:33:22

When I walked outside, yes, it happend at the same location, the highest elevation of the course, because that's where I was during that period. I do that same area three more times during the walk and it's only the first time.  It also happens at the same (clock) time on the treadmill so the problem isn't more exertion. Yes, on the treadmill I do an hour at 2.5-degrees, an hour at 2.0, and 1.5 for the final hour.

I had three unsuccessful ablations for atypical flutter in a year.  After the first, my EP wasn't encouraged but kept trying. After the third, he know it was hopeless.  I had my pacemaker implanted a month later so with the added AV ablation the problem finally went away.

I'm not sure where to go from here.  As I said, I see my cardiologist in two weeks (I had to cancel a month ago because I had covid).  I'll get results of the PET scan so if there is a blood supply problem, it should show.

I'm not sure why he hasn't use a Linq recorder in the past.  I've had a dozen Holters for two days to two weeks but a Linq was never discussed.  I'll find out what the PM tech says tomorrow.  Maybe a treadmill test is in order. A lot depends on what, or if, the PM interrogation comes up with.



Chest tightness as a symptom of myocardial ischaemia isn't necessarily coronary narrowing

by crustyg - 2022-07-26 15:21:28

When I was studying (back in the day) there was a vigorous debate - could sympathetic drive cause coronary constriction bad enough to cause heart pain +/- infarct - because there's a local auto-regulation that causes smooth muscle to relax?  Turns out that factors *can* cause acute coronary narrowing enough to cause serious problems (and no, I'm not referring to cocaine).

It was called Prinzmetal's Angina, now Unstable Angina. On a normal angio there's not always anything to see.  Requires a stressor to cause the reduction in blood supply.

But in your case, Agent, I'm suggesting that running your ventricles at 140BPM for 10min is enough to push some heart muscle into ischaemia.  Remember that coronary blood flow is *only* during diastole - so a sharply increased HR means much less oxygenated blood supply AND much more oxygen demand - chest tightness.

What is Prinzmetal angina?

by AgentX86 - 2022-07-26 21:26:13


"It usually happens between midnight and the morning while you’re asleep or resting."

That's a good point about 140bpm and diastole. It sounds like a reasonable guess.  My HR isn't supposed to get there and I hadn't noticed it getting anywhere close before (110-115 max).

I did have the (chemical) stress PET test a couple  of months ago.  As  I said, I had to cancel the appointment to get the results and it's been rescheduled for the 10th. If there were anything abnormal, I'd have expected a call much earlier.

I'll post if I find anything out tomorrow. The device tech obviously can't get this deep but perhaps I can rule out anything odd happening with my PM and make sure the settings are what I think they are.


Verrrry interesting

by Lavender - 2022-07-27 09:29:24

Watching you all brainstorming is fascinating! I'm awed at your knowledge as you discuss possibilities!🤩

AgentX86, will be awaiting your report on the case! Godspeed!


by AgentX86 - 2022-07-27 10:02:07

Nothing.  Appointment was cancelled at the last minute (as I was walking out the door).  The EP had an emergency so wasn't in the office.  Come back next week. Same bat-time, same bat-station. 😑

Odd revelation

by Lavender - 2022-07-27 11:01:18

Well it looks like you got another odd revelation today. 🙃 lol at the bat-ty reference!

As you said, you never received the results of your PET scan. No one called to order you to the ER, so on we go. Sometimes I feel like we're all wandering on our own. As Dylan said,  "To be on your own, with no direction home A complete unknown, like a rolling stone"☮️

Disappointing, but

by Gemita - 2022-07-27 11:02:56

any chance of getting a holter monitor for a few days or for the week and taking more information to them when you attend, to correlate perhaps with your pacemaker checks for the same period?  I would take advantage of the extra time and try to move ahead nonetheless.  Other than that, you will have to make lots of diary notes, with time, date and description of symptoms and take your home monitoring data to them to back up your own written notes and then correlate these with your pacemaker latest downloads.   The more data we can supply, the more likely we are to get results and a likely diagnosis, or plan of action.


by AgentX86 - 2022-07-27 12:22:57

Thanks, Gemita.  I hadn't been taking notes.  I'll start today.  I have notes on my seizure aura going back several years (nothing in the last year). I haven't been taking notes on anything heart related for some time (dummy). The last time (bigeminal PVCs) I was able to capture it on the Merlin box and the device tech was able to identify the problem in seconds.  I should do it with the app, now that I have it.  I'll have the perfect time to discuss it next Wednesday and if there is anything there, the following Wednesday with my cardiologist (sheesh, some people are dense!

Thanks again.

And if nothing else…

by Lavender - 2022-07-27 12:32:39

Good going, Gemita!

AgentX86, if nothing else, you get the award for the most comments on a post in recent memory! Again, I enjoy the camaraderie and concern shown here by everyone to one another! 

Failed ablations

by Lavender - 2022-07-28 08:49:59

Here's an article about pathways growing back:



by AgentX86 - 2022-07-29 20:41:43

An Afib ablations is quite different than an AV ablation.  In the first case, the EP "draws" a line of scars in the way of an errant electrical path. This scar tissue doesn't conduct electricity so the AF, AFL, source is isolated where it can't cause trouble.  Often this scaring isn't complete but is good enough at first but breaks down or heals over later.  As the heart disease progresses, another site starts doing its thing causing the ablation to "fail".

During an AV ablation, the EP actually burns out the AV node completely.  Once these nerve bundles are destroyed, they don't grow back. In my case (I don't know if it's universal), in addition to the AV node being burned out, the Bundle of His was also ablated.

You know you're wired when...

Your pacemaker receives radio frequencies.

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