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Heart rate tracker anomalies

LadyZ13 profile image
32 Replies

Hi everyone,

I'm getting quite anxious due to my Fitbit reporting strange peaks in my heart rate. This was 4:37 this morning, and back to 70bpm 3 mins later. I slept through this so have no idea if it's accurate.

Yesterday it said my heart was 187bpm while I was walking briskly to meet someone for lunch. I'm trialling another AFib detecting monitor that shows HR which said 110bpm at this point, but the two devices rarely seem to agree!

The day before, Fitbit suggested HR of 160bpm while I was chopping vegetables. I checked my pulse and took the thing off, dismissing it.

When you can't calmly verify a reading, it's very unsettling to see these unexpected peaks, especially after open heart surgery, a period of AFL and a (successful🤞) cardioversion.

What would you do in my situation? Thank you in advance.

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LadyZ13 profile image
LadyZ13
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32 Replies
Teresa156 profile image
Teresa156

Hi LadyZ13,

This is a difficult one. I really sympathise and know how much anxiety these watches can bring, when you avidly check your HR on them, which we are very likely to do, with our condition.

I have an Applewatch and I know for a fact, that it gives strange blip peak readings, if for example, I’m in the car ( passenger or driving) and go over a very bumpy road. It also can give a peak reading if I’m doing vigorous housework with my arm, such as wiping, or scrubbing something quickly. It gets confused.

I don’t know if FitBits are the same, is it tight enough on your wrist?

The fact you said that it went to 160 whilst chopping vegetables suggests to me that it might be misreading signals and that your ‘vigourous’ chopping was misread as heart beats, perhaps?

Have you had it a long time?

LadyZ13 profile image
LadyZ13 in reply to Teresa156

Thanks Teresa, I appreciate the reply. I've had this particular device since Dec 2020 but never used to pay much attention to HR other than when being told to get to Peak during HIIT classes! How a heart issue suddenly changes all of that. I've been combing though old charts for odd standalone peaks and there are a few (126 at midnight 18 months ago...) so clearly it can get in a muddle, but it seems to be happening more often now I'm hyper aware.

Ulimately all the home machines say I'm in NSR and I feel OK and my HR is OK apart from (apparently) a couple of minutes a day if there's a weird peak... I think, even if it were actually elevated, this would only be harmful if it was persisting for 30 mins+? So the wisdom would be to put it out of your mind and not fret, right??

Teresa156 profile image
Teresa156 in reply to LadyZ13

Hi LadyZ13,

I would say yes, you are right & I (think) it would be worse if it persisted and perhaps best not to fret( I edited my previous typos, apologies!) however, I probably would still wonder about it, if I’m really honest, ( but I’m a born worrier) and I think you might too, in reality? Especially as you are noticing it more?

The trouble with Afib etc, as we know, is that you need to capture it when it happens, which is tricky. I’m not sure what the lifespan is too for Fitbits? Wonder if it’s worth googling, or seeing if there are any forums where other fitbit users notice spikes?

The only other option I think you have, if it persists, is to mention it to your Dr and ask for a holter monitor, perhaps a 3 day one, or even a week of possible? but I know the waiting list for those can be quite long these days.

LadyZ13 profile image
LadyZ13 in reply to Teresa156

Yes, once you notice something like this, you do go on to notice it more! Sod's law.

Interesting point on Fitbit lifespans. Google says 2 years, so mine coming up 3 might be showing signs of geriatric behaviour! I've seen some reports of spikes on forums,so it can happen. But with a cardiac history you worry more.

I'm seeing my consultant at the end of next month and I will absolutely mention it. I've mentioned it to rehab and my consultant before but it only piques interest if the Fitbit flags an Afib episode and it's corroborated by an ECG. Also, they never tell you the detail of the holter beyond '99% normal beats' or whatever - I'd love for a detailed 'yes, there was this weird 160bpm when you seemed to be otherwise at rest, did you happen to notice anything...' so that you can compare readings. I think my most senisble option is probably not to worry and mention it at my next appointment if it's still happening.

Teresa156 profile image
Teresa156 in reply to LadyZ13

Your plan sounds like a good one to me…yes, try hard to ignore any more random blips if you can - regarding lifespans of fitbits, I wouldn’t be surprised if my Apple watch is on the way out too.

Yes, I go agree with you about the Monitor results. I often wonder who trawls through the results, there must be thousands and thousands of heartbeats to check…I’d like to think they do though, but come to think of it, they don’t go into detail do they? 😳

I hope they stop for you soon though. Take care.

LadyZ13 profile image
LadyZ13 in reply to Teresa156

I would imagine holter tapes are all read by AI these days - it's the sort of thing a machine can examine more efficiently than a human to pull out anomalies. It probably writes a report and flags areas of interest for a Human to look at.

Thanks for engaging with my fretting and for your kindness. I appreciate it.

Teresa156 profile image
Teresa156 in reply to LadyZ13

Yes, of course, AI - I should have thought of that, it’s everywhere.

You are very welcome…please let us know how you get on. We’re all in this together.

Take care.

Jctga profile image
Jctga in reply to LadyZ13

I get the same peaks when walking for exercise and more rarely while sitting. They are followed by a few minutes of heart rate in 120’s and fatigue. No one has been able to explain it for me. Very disconcerting.

LadyZ13 profile image
LadyZ13 in reply to Jctga

That's odd, and strange that it's accompanied by fatigue. Do you take your pulse in wrist or neck to compare?

Jctga profile image
Jctga in reply to LadyZ13

Wrist. With difficulty. Also was able to get an ECG this last time.

Blearyeyed profile image
Blearyeyed

As Teresa156 has said sometimes anomalies on devices can happen because of how tightly they need to be worn , some movement or leaning on them can cause a ' blip' .It's why it's often wise to wear it on your non dominant arm during the day , especially during exercise or housework.

This can even happen at regular times strangely enough because it may just be a time when you are more physically active in your sleep.

The same can happen because of the arm you wear them on .

I know this sounds odd , but one thing they often do in a surgery is check your BP/ HR in both arms to see if there is a difference if they get an unusual reading.

Often they prefer to take your BP/ HR on your dominant side because the muscle strength is better and it gives better results.

So it may be worth testing your two devices by wearing your new device on the arm that is giving you anomaly results and seeing if the same thing happens , and whether the old device gives normal results on the other side.

It could indicate that you're devices are fine but you could still be leaning on that side at night , so see what the results are like by only using one on the other arm.

But , it's always worth noting , especially if you are getting it regularly or having issues during activity in the day . So if it continues , print off the readings and speak to the GP about it.

Sometimes it can show that your circulation is a little slower or faster in the one side but unless that's regular or there is a big difference between cuff BP readings on right and left they aren't usually too concerned.

Despite having a Tachycardia Syndrome, my smart watch did point out that I get a nightly moment of Bradycardia and very low BP, which was around the same time as you and actually waking me up. It was in line with the time the body's clock begins to make normal chemical changes to prepare itself for finally waking you up, which coincidentally happens to be around 4-5am.

LadyZ13 profile image
LadyZ13 in reply to Blearyeyed

That's a really interesting piece of information - thank you! As it happens, I had moved my Fitbit to my dominant arm just before getting the odd reading - though it was on the usual non-dom during the vegetable cutting... And both wrists have red raised lumps due to the straps - the Caridacsense causes them under the wrist but the Fitbit is on top near the sensor so maybe that's also a thing?? More experimentation needed! Though I'm returning the test device next week so then I lose the second reading for comparison... Do I want a new one? Or do I just want a super-basic watch next?! 😆

Blearyeyed profile image
Blearyeyed in reply to LadyZ13

Most watches are just a guideline really , especially when it comes to blood pressure as those reading on based upon an algorithm using your heart rate readings , and the algorithm was created from the average for the generally healthy population rather than for people with certain cardiac conditions.My smart watch often gives me wildly different BP readings to a cuff BP because I have Tachycardia. It also usually tells me I've gone to sleep an hour before I do and I've got up an hour before I'm awake because my heart rate is usually high and therefore outside the usual parameters.

I get skin reactions from having to wear it tightly and need to swap the watch if I swap it or slightly loosen it reading go a bit off. I'd tried my daughter's Applewatch to see if expense would improve the readings but no, the basic health algorithms are the same no matter which watch us being used. I just keep to my basic watch now and swap it to help reduce the effect on my skin.

They are good to wear for a guideline to get you to slow your pace if heart rate goes too high during exercise and helpful if you get repetitive anomalies to print off for the GP , and helpful to track your activity or steps but I wouldn't rely on them medically. And people can get a little bit anxious with them which can defeat the object.

If I do feel concerned I use my cuff monitor for proper readings and I also have a Kardia 6L for checking AF and Arrhythmias.

LadyZ13 profile image
LadyZ13 in reply to Blearyeyed

This sounds like a smart approach! I was particularly interested by the comments about sleep tracking. The 'lower readings' device thinks I've had about 30-60 mins more sleep than I have, whereas the Fitbit thinks I'm awake, tracking 10-30 beats higher. I was offered a HR monitor in my face to face rehab class so I think I'll try that too. I don't think there are disproportionate peaks during exercise, and the couple of stress tests got me up to 160bpm at an extended 10 mets. All the date is useful, but only if it helps you. I'm wondering if perhaps it's not helping me much now, just creating unnecessary worries...

RumblingChest profile image
RumblingChest

Hello LadyZ13,

I recently read an ‘x-let’ (or whatever tweets are called now) by a doctor objecting to all these wearables creating unnecessary anxiety. But on the other hand, the records from mine (ECG) got my GP fired up and got my hole found, without them, who knows? Previous GP dismissed palpitations 10 years ago…

I think you have to remember these devices are not “medical” or perfect. Even those clippy finger things they put on you in hospital are subject to glitches when you move about. So I would not trust the data as gospel, especially if you are feeling ok in general.

I was worrying about AF post-procedurally as well, I kept waking up in the early hours and had strange sensations at times. A few times I did manage to capture a dodgy rhythm or a bit of AF with the ECG on my watch, but since it often seemed to feel weird during exertion, that wasn’t very successful - it’s quite hard to keep your finger on the button whilst running! I even bought a 3 electrode 24 hour ECG monitor from Amazon to wear, but the readings were pretty noisy with any movement, although it was okish overnight. So I’ve done the data chasing thing 😀. My wife told me I was getting obsessed and if I was really worried I should get a monitor from the cardiologist 😀.

In the end I stick to using my watch ECG function if I feel weird and just assume that my heart is more likely to misbehave during the day than when I’m asleep. But most of the time when I thought I had a weird rhythm it either wasn’t or resolved before I could get the ECG reading. Fortunately, the weirdies seem to be less and less as time passes.

So in short, I think the HRM is not really helping you - it’s sort of the wrong way round - calling your attention to the device when you hadn’t noticed anything yourself, but not able to provide conclusive evidence of anything. I’d say you either need to ignore very occasional peaks as mostly likely glitches (put the Fitbit in the drawer for a month 😀) or go down the route of a device with better capability to record rhythm, whether that’s a consumer ECG such as a Kardia for ‘on-demand’ checking or chasing your cardiologist for a Holter. It comes down to which option is most likely to put your mind at rest.

You’ve had one heck of a journey, it’s not something anyone would be able to just put behind them. I wonder if you have access to appropriate counselling that might also help - perhaps the Somerville Foundation?

Take care,

RC.

LadyZ13 profile image
LadyZ13 in reply to RumblingChest

Hey RC, lovely to hear from you - thank you for such a compassionate and considered comment and for sharing your own experience. It's so easy to get hung up on things, even when you feel OK or normal. I think I was thrown by the Fitbit flagging AFib during my recovery - I wouldn't have known there was an arrythmia without it. You then stop trusting your own sense of what's going on with your body.

2023 has indeed been a hell of a year. I'm so new to health anxiety, relatively speaking, that I don't yet have solid coping strategies. My current focus is the review with my consultant at the end of November. I'm hoping she says everything is OK, that I'm recovering well, and I can get all my questions answered. But of course there the fear that something unexpected might occur, the rhythm is out, the valves have a problem, they'll need to do a further surgery at some point. It's all scary, and even as a fairly emotionally robust person with good support, I find I'm feeling sad, worried and lost more than I used to. Cardiac rehab referred me to PWS but that was 4 months ago and I've heard nothing. I do have a few other avenues to try, but the Somerville Foundation is a good shout. Thank you.

Have a lovely Sunday,

Zoë

kkatz profile image
kkatz

I don't know what Fitbit you have but my fitbit charge 4 is absolutely rubbish .On exercise walking or classes it shows high readings that can't possibly be correct.I have dug out my old charge 2 and although the display is not as good it is much more accurate.I also use an Huawei and it gives the odd low or high peak during the night.

LadyZ13 profile image
LadyZ13 in reply to kkatz

Thank you, that's reassuring!

Ppiman profile image
Ppiman

My Apple Watch does the same. I have read that it's to be ignored as it's a "blip" caused by some artefact in the hardware / software that doubles the actual beat. The ECG app on the Apple Watch does not do this. Certainly, mine has proved to be of no consequence as I am thinking yours will, too.

One way to check this is to run an ECG for a few hours. I bought a Wellue 24-hour home ECG monitor direct from the company for just this and it's been a marvellous device that has produced very full AI based reports of my heart's activity. It's worth a look on their website.

I attach a heart rate trace from my Apple Health app.

Steve

Hert rate spike on Apple Watch
Sustainedvtach270 profile image
Sustainedvtach270

Hello Lady Z, I had a similar experience, a few weeks ago I got a new smart watch, a cheap Chinese import on Amazon. I paid attention to the HR for one day, every time I talked the HR would jump to 120s, same thing if I walked, I became all worked up because I have not felt any palpitations lately. So I compared the watch HR with a clippy finger I have been using for a while, the watch HR was about double... So I now only use the watch to keep track of my steps and for the slow breathing app. Is there any reliable watch besides Apple?Thierry

LadyZ13 profile image
LadyZ13 in reply to Sustainedvtach270

I'd assumed Fitbits to be up there for reliability, they were kind of market leaders and their AFib detection is medically certified as being legit. I wondered if it was being messed up by any ectopics or similar (I have very brief sensations of missed beats a few times a day) but I don't see how that would happen within my understanding of the technology! A friend who is a pilot says the cockpit has three instruments reading the same thing so that it one breaks it's obvious which one because the other two mostly agree. Temporarily, I have 2 HR wrist devices and they're crazy! I don't know which one is 'out' during my exercise periods. Very frustrating.

Two fitness trackers, one showing 84 beats a minute, the other showing 146.
frazeej profile image
frazeej

I have a FitBitSense and also get those spurious blip of abnormally high HR. When I put the watch back on after a shower, a 120+ HR blip will occur. It's nonsense. Others will occur during the day or night with no explanation-and they are always just a single peak, not of any duration. When in afib, of course the high HR peaks are of much greater number and duration. I've learned to ignore these single blip anomalies.

I have found that the watch is very sensitive to either the strap being too loose or too tight, and also any abnormal hand movements. I also wonder, if FitBit can't give me this simple piece of data accurately, are any of the other data pieces at all reliable? Thumb on the pulse is still the fail safe method!

JimF

LadyZ13 profile image
LadyZ13 in reply to frazeej

I am so reassured by your assessment that the blips are nonsense! I have lost all confidence in 'listening to my body' after being diagnosed with a serious heart issue that required me to have open heart surgery, while I was completely without symptoms. I keep shifting the Fitbit between wrists (it rubs and irritates my skin sometimes) - and I remember it went loopy when I was shaking a protein shake mixer! Yup, fingertips on pulse is clearly the way to go!

intheweeds profile image
intheweeds

I wore my fitbit inspire 2 for a year before taking it off! It was making me a bit obsessed with every high reading. If my HR is peaking for any reason and I cannot feel it, how bad can it be. When I was wearing it and my HR peaked, there was nothing I could do about it anyway.

Good luck with your device, its probably better than my cheap one and more accurate.

LadyZ13 profile image
LadyZ13 in reply to intheweeds

I am trying to lean towards that 'how bad can it be?' thought. If you feel OK and the pulse in your wrist/neck doesn't feel troubling, then probably the equipment is playing up. Thanks for pitching in with your experience :)

mav7 profile image
mav7

May be best to ask your doctor to wear a holter monitor for an extended period and compare results with the Fitbit. Nothing beats a medical device.

LadyZ13 profile image
LadyZ13 in reply to mav7

I could but 1. I don't think they'd just give me one unless there was suspicion of particular issues like AFib and 2. You don't get to see the result of the holter, they just tell you what they want to do afterwards, and sometimes you might get told that X% of your beats were normal or that they saw ectopics or fib. It'd be great if you could have 3 days of data to hold up against the Fitbit and comb through...

Bunkular profile image
Bunkular

The fact that the watch records the accelerated HR only for a min seems weird. I would have someone else wear the watch for 24 hours to check it out and also see if you can borrow a different smart watch for a short time as well. Ask your doctor for input - you may have to wear a Holter monitor for a few days.

LadyZ13 profile image
LadyZ13 in reply to Bunkular

Yup, using two smart watches now and the second one shows something different! Thinking possibly the almost-3-year-old Fitbit might be on the way out - it also crashed on a walk earlier instead of marking my step goal and lost data, and just now it said 130bpm while my pulse at wrist was 76bpm... See comment above about holter...

frazeej profile image
frazeej

Followup to original reply: This is real time. Note the one spurious peak of HR ~96. That occured when I removed the FitBit from my wrist and placed it on the bureau, prior to shower. See the gap in HR (OMG I must be dead!!!), and then resumption of normal HR after shower. In other words, the one data point out of line means nothing, it's the fault of the watch! JimF

Resting heart rate
LadyZ13 profile image
LadyZ13 in reply to frazeej

That's reassuring! Mine are more like up to 120-180 in their peak points, but I have much more variability at rest, 60-100.

frazeej profile image
frazeej in reply to LadyZ13

Yes, the blip of 96bpm was an unusually low "pre-shower" reading, frequently 130-140. Maybe the top of my bureau where the watch is resting is vibrating??!! LOL!!

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