What are normal Heart rate fluctuations with Pacemaker?

I've been a cyclist for years. 6 weeks ago I had an ablation done and a Biotronik pacemaker implanted. My condition before this was described as 2nd degree AV block, bradycardia, chronotropic incompetence, SVT and atrial flutter.  Symptoms were increasingly difficult getting my HR up when exercising making me feel short of breath, problems also when sleeping, feeling fluttering in chest and shortness of breath (sensation is kind of like something suddenly obstructing my breathing, and can disappear as suddenly as it appears).

My previous max HR was ~160, doctor initially set my PM as 60bpm lower and 140bpm upper limits. But the PM was frequently bringing my HR up to 140 with very little activity, so he decreased the sensitivity and also lowered the upper pacing to 120.  It seems a little better, but still seems like my HR moves unpredictably and in steps.  Say I go for a steady paced walk, it often stays at 85-90bpm for a half hour, then it will suddenly step up to 120bpm and stay there for an extended period, then it might drop down to 100 and stay there for a while, and sometimes it will drop down to 60bpm and stay there for a while.  Is this normal HR behavior with a Pacemaker?  Usually when my HR is moving around like that I wouldn't even know it except I'm watching my HRM data.

The 2nd concern I have is riding the bike I feel fairly comfortable with my zHR in the 120's, but seems as soon as it hits 130 I get that fluttering sensation and sudden shortness of breath sensation like something obstructing my breathing. Sometimes that feeling just last a second or 2.  I've been testing it to see how I feel, so I can talk to the EP doc again shortly, but when I've felt those sensations, I back off.  These sensations are similar to what I felt before I had the ablation and PM implant only now seem to be occurring at a much lower HR.  So I don't know if this sensation is related to the PM or if there is still something else going on.  Anyone familiar with this sort of sensation?

I should also mention there haven't been any events or arrhythmia's reported by the Biotronik monitor. 



This isn't right.

by crustyg - 2021-11-24 17:55:46

Just because nothing's being recorded in your PM's event/rhythm log doesn't mean that you aren't having episodes of some form of arrhythmia.  Sadly, there's not an absolute guarantee that you won't have a recurrence of AFlut or some SVT, and it would probably feel exactly like this.

PM's won't record anything that they've not been programmed for: you'd be better off with a Holter or implanted reveal device for a few weeks.

I'm also a keen road cyclist: two ablations (nine months apart) and even though I've been in sinus rhythm since the second one, if I push too hard going up the mountains (and let myself get really dehydrated) then I can precipitate some disordered rhythm - my chest strap suddenly shows a massive drop in HR, I feel terrible and I stop.  Never yet been able to capture this with a portable single-lead ECG, and it's not easy to feel my carotid pulse under these conditions.  I stop, wait 1min and then feel better and carry on, with a little less effort.  My EP-doc also set my maxHR low for the first 6weeks after implantation, but let me have 160BPM after that.  Which is much more realistic for my age and heart-muscle health.

There are a few contributors here who've had something like a Linq reveal device implanted post PM and it's been very helpful to prove what's been going on that the PM is missing.

Hope that helps.

Best wishes.


by dlbdata - 2021-11-25 13:18:16

Thanks Crustyg, appreciate you sharing your experiences.  Yes I think I'm going to contact the EP doc next week and see what he thinks about the halter.  I did a couple rides this week, and as soon as I hit 130bpm it starts feeling fluttery and shirtness of breath.  I felt pretty tired yesterday afterwards. This seems worse than before I had the ablation and PM!

HR Dropping

by lrmcnulty - 2021-11-30 04:20:07

I am a cyclist & 4 months post PM for Bradycardia, Chronotropic Incompetence & heart stopping episodes while asleep.  I experience the same symptoms as you while riding - that dreadful fluttering feeling in my chest, confusion & lack of oxygen - I know what you are going through.  I had the holter monitor (post-PM) while riding to try & get it sorted & the holter did capture these episodes.  It has now come down to getting those PM settings correct for my active physiology.  Some days are better than others on the bike & as soon as I start to feel a flutter I start tapping the PM to elevate my HR - works most of the time though, not ideal.  It will be a process getting the PM customised for my active lifestyle though, I am patient & at least I am 'back out there'.  Hope you get it sorted.  Take care.

You know you're wired when...

You prefer rechargeable batteries.

Member Quotes

Good luck with your surgery. It will improve life amazingly.