I use both for checking my heart rate and checking for Afib, and my cardio consultant endorsed the Kardio monitor. He was though rather sceptical about Fitbit watch saying it was very limited.
I wondered what experiences others had about these devices.
I also had a question about heart rate versus pulse. When I am in Afib and experiencing palpitations they do not appear to be the same.
I feel my heart thumping but my heart rate whilst clearly in Afib is much less chaotic. It feels like neither monitor, nor a manual pulse check is reflecting how I feel my heartbeat in my chest.
Hence my question, can my heartbeat be different to my pulse?
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Crimson2020
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Yes all the cardio nurses cardiologists and EP's have told me the Fit bit is not so good as the Kardia. I use the fit bit to see what has happened during the day - I have an old Charge 2 so it won't show when in AF just heart rate and an average resting rate for the time I have it on which is what i am most interested in to see if my resting heart rate is getting high. The good thing about the Kardia is that the graphs can be e mailed to your specialist or Cardio nurse and be read by a professional. Having said that I did notice that a lot of the nurses actually wore a fitbit. I am sure the Apple Watches are really good but know nothing about them and I know I could not use one as I wouldn't be able to see it or use it as my fingers are too big - Have enough problems with an iphone. I can barely see my fibit when wearing it - sometimes can't even see the time . I have to go into the shade to try and read it if outside or near windows and even then often have to get my wife to look.
Kardia counts the electrical impulses, which don’t always translate into a detectable heartbeat/pulse because the ventricles can’t keep up. Fitbit or similar count pulses (blood flow through blood vessels) so unless you have only slightly irregular or slowish AF will show less beats than Kardia. If you have very irregular AF it feels more like ectopics and sometimes ‘AF’ will be diagnosed as frequent ectopics by an expert.
TBH, if I am on the move, away from home doing outside stuff, walking etc. and I want to know my HR I just glance at my watch to get an idea but I have never regarded it as spot on accurate. Just gives me a ball park figure.
I've always understood that HR and Pulse Rate are basically the same animal. I've also been told that HR/Pulse Rate alone is inadequate ..... most desirable to know what blood pressure is doing as well if you can capture that info.
My watch is a Withings which gives a range of data, ECG, Blood Oxygen, Heart Rate etc but I never rely on it. Its just ball park stuff. (The Withings of course does not give blood pressure). If it gives weird readings then when I get home I run a blood pressure check and a Kardia check – the latter will of course give me an ECG and heart rate.
For my blood pressure check only at home I use I my NICE approved Blood Pressure monitor ............ mine will also indicate/warn that my heart is beating in an irregular manner.
I have fit bit sense 2 , I also have Kardia, I recently added a Polar H10 for when I am exercising. The Fitbit was showing a lot of HR spikes say 140 when exercising , I compare the Fitbit to Polar when exercising and the difference can be 20-30 Bpm, thecPolar shows less peaks, in fact hardly any. I am glad I bought the Polar , assuming it is accurate it has given me some re assurance. Conclusion on the Fitbit is that it’s maybe a very rough guide and maybe not so accurate? I havnt tried the Apple Watch , it’s a bit expensive for just a trial and then Fitbit battery is good for 5 days. I don’t so far have AF, looks like tachycardia and PVC.
13 years of intense very clearly defined Afib… Apple Watch gave consistently poor readings- Kardia was consistently accurate and taught me more details of my arrhythmias! Hope you find the best solution for you!
I use Kardia to record episodes for my cardiologists and obviously for my own use. I use Fitbit to record any nighttime episodes - ones I might not be aware of. I have found it pretty good for this. I recognise it may not be 100% but it has been approved in US by FDA and I think at 98% accuracy
I have a Fitbit Charge 6 and I get the irregular rhythm notifications without the paid subscription service.
I have though taken up the paid Kardia Mobile subscription at £9.99 per month. This gives a more detailed analysis and I would be reluctant to go back to the limited analysis version.
To date though I haven't seen any benefit for me to "upgrade" from the 2 lead Kardia to the 6 lead version at £149.00
When I try to set up afib notifications, my Fitbit Charge 6 tells me this: "If you have a prior diagnosis of atrial fibrillation (Afib) or are under 22 years of age, this feature is not available to you."
If I say No (not the truth), then I would be allowed to set up notifications.
But then I'm informed of all the ways that Google will share this information. Well, I suppose that horse has left the barn, but still, it gives me pause. It seems much more certain that my diagnosis will be spread far and wide.
Does anyone know why Fitbit has this policy? Is it some kind of protection against lawsuits or something?
The six-lead Kardia yields six different EKGs.
They are labeled I, II, III, aVR, aVL, and aVF.
You get type I with the fingers-only model. The additional five types come with the fingers-and-knee model.
I don't yet know what the other five are for, but my cardiologist seemed to find them useful.
Also, the six-lead model will inform you of several other problems, such as Wide QRS (or something like that). Seems to me that this is wrong -- to withhold important info for money. (What else is new?)
Heart rate (HR) and pulse have been used interchangeably and is defined as the number of times your heart beats in 60 seconds. There have also been subtle definition differences between heart rate and pulse rate. Heart rate is usually best measured electrically by an ECG. Often times, pulse is measured at the wrist by how many times the arteries expand and contract. This gets into the debatable differences in accuracy between electrical measurements of ECG and optical measurements at the wrist.
I, too, have both a Fitbit (Charge 6) and a KardiaMobile 6L. I find the two devices complement each other. The Fitbit is useful when I am out and about. It gives a somewhat accurate measure of heart rate. It also has a handy 30 second measurement of lead 1 ECG which accurately tells me if I'm in normal sinus rhythm or in irregular heart rhythm. The downside of the Fitbit is that the wrist optical sensors are sometimes inaccurate. It gives a good ballpark estimate of HR but it is not so dependable. Often, there are inaccurate spikes and sometimes it misses rapid changes in heart rate. Instead, I prefer either a Polar H10 chest strap or a Polar Verity Sense arm band to give me more accurate HR when I am exercising and need to accurately track my HR. The Fitbit ECG is pretty accurate when it comes to showing the R waves (spikes on the ECG chart). But the details of the ECG graph is poor and making out the p-waves can be a challenge.
The KardiaMobile 6L is far superior in measuring and displaying ECG results at the expense of portability. I use the Kardia at home and always use the 6 lead measurements (two thumbs and the left leg). I find lead 2 gives the most accurate display of how my heart is behaving, showing clearly the p-wave, QRS complex, and having less artifacts. However, their "determinations" are pretty vague if you have an irregular heart rhythm, too often reporting "possible atrial fibrillation" as a catch-all determination. Learning to interpret your own ECG is the best solution. I draw my conclusions on what my heart is doing from my Kardia. If I need a quick and second opinion, I send a 60 second ECG report to a Kardia doctor (paying a small fee) for his more accurate determination.
In regards to heart rate, the Kardia 6L tends to over-report the heart rate, which is defined as the number of times the heart beats in 60 seconds. If you are in an irregular heart rhythm and you count the number of R waves (upward spike on the ECG graph) over 60 seconds, it is often much lower than what Kardia reports in their summary. The reason is that Kardia does NOT count the R waves over 60 seconds but uses a different method. This is what they emailed me...
"Kardia does not calculate beats per minute based upon simply counting the beats, but takes into account interval variability and uses the median RR interval of the beats with good signal quality. In cases where the heart rate variability is great, such as atrial fibrillation, this number can be quite different from the beats per minute obtained by directly counting the beats."
To conclude, both the Fitbit Charge 6 and KardiaMobile 6L can be useful for tracking my irregular heart rhythm. The Fitbit gives me a rough indication of heart rate and rhythm (via their ECG) when I am out and about. Then I use the Kardia 6L when at home to confirm the numbers as well as to draw a conclusion. Hope this helps.
Thank you very much for the info about how Kardia determines beats per minute.
I checked a few tracings of mine, and I counted 120 when Karia reported 138. A small comfort, I suppose. But my tracing was so chaotic at points that counting an R was a bit iffy.
Speaking of chaotic, I could not get a Kardia reading while a vacuum cleaner was being used nearby. The device said there was interference. Has anyone had this experience?
Would there be a way for a Karida to undercount?
I know that my Fitbit watch is not reliable as a BPM counter when I'm in afib. It will report 59 when the truth is 130. In fact, I can use 59s on the Fitbit as a suggestion that I'm actually in rapid afib. I simply pay attention to my actual physical feelings, and then I know.
Most of the time, though, the Fitbit reports seem reliable, and they are helpful to assure me that my resting BPMs are far lower than the used to be (60s as opposed to 80s).
Hello Corazon17, regarding your vacuum cleaner interfering with the Kardia, I tested this with my Miele vacuum right next to me while I used the Kardia... no interference. Perhaps its time for a new vacuum
As for the Kardia under-reporting heart rate, yes, it does happen when your heart rate is very low (Bradycardia). I've had instances when I counted 56 beats per minute using R waves and Kardia reported a heart rate of 48. For irregular heart rhythms, Kardia's heart rate algorithm tends to under-report heart rate when the heart rate is low and over-report when the heart rate is high. Those of us with irregular heart rhythms tend to land on the high side so Kardia's over-reporting of heart rate is something Kardia's users should be aware of. In cases of irregular heart rhythm, instead of reporting one heart rate that is of questionable value, I would like to see an average heart rate as well as a max heart rate.
The only reliable HR check while in AF is the average electrically via an ECG which the kardia does and gives you an average HR over the period of the ECG which I believe is 30 seconds as on my Apple Watch ECG.
All the devices have pulse detection, usually optically on watches and by pressure detection on BP monitors, all of which are pretty unreliable when in AF as the beat to beat is varying so much from beat to beat. Only the watches with ECG function can do the electrical heart beat check and most brands have at least one of them. Also when feeling your pulse radially in your arm then not all the rogue pulses with AF are detectable so the results again can be unreliable in some patients.
I have been feeling slight flutters in much chest and stomach for about 2 hours which started just after eating lunch. At times though during thess 2 hours the symptoms disappeared.
My Kardia initially registered Sinus rhythm with Premature Ventricular Contractions but then gave me Unclassified, Bradycardia and Normal Sinus Rhythm.
The symptoms have just returned and my Fitbit watch indicated Afib whilst my Kardia is once more indicating SR with PVCs.
I have two questions as follows.
1. Does the Fitbit Charge 5 have an indication of SR with PVCs? and
2. Has anyone else noticed an initial Kardia indication of SR with PVCs in the lead up to a full Afib episode.
Edit: I forgot to mention experiencing symptoms of polyuria for about 24 hours now and a dull ache in the neck and head for about 2 hours.
I, too, have had frequent PVCs and use both the Fitbit Charge 6 and the Kardia 6L to monitor my heart. For your first question, no, the Fitbit Charge 5 and 6 do not know about PVCs. From the 30 second Fitbit ECG report, it will either report "Inconclusive" or "Atrial Fibrillation" if it detects many PVCs. For 24 hour monitoring, the Fitbit can detect Afib but not PVCs. PVCs are pretty easy to recognize on an ECG graph so you can make the determination yourself. You can do a search using "how to recognize PVCs on an ECG".
As to whether SR with PVCs can lead to an Afib episode, it is my understanding that the higher the PVC burden, the higher the risk of Afib. However, just having PVCs (especially those with a low burden) does not necessarily mean that you will end up with Afib. Of course, this is only my non-medical opinion after some research on the matter.
As you have found, the Kardia determinations can be confusing. I have found that they give you a general indication of your heart rhythm but can often be misleading. Sometimes, it can classify PVCs but not at other times. It also gives "Unclassified" and "Atrial Fibrillation" determinations as a general catch-all for many specific heart rhythms. The ECG chart itself is what is useful and I find that the Kardia 6L gives clearest results on Lead 2. Taking the time to read ECG's really pays for determining what your heart is doing. Another option is to pay a small fee to have one of Kardia's cardiologists give a second opinion, sending them a 60 second ECG report. I have read many who recommend sending a 60 second ECG report to your doctor but I have not had much luck with my GP or cardiologist wanting to read my Kardia ECG reports. Perhaps your doctor will be more accommodating.
Having many symptoms can be scary and unsettling. Hope your symptoms improve and your PVCs will not lead to an Afib episode.
I am currently experiencing Afib episodes 3 times a month each recently lasting 18 hours. Fortunately my symptoms of palpitations, fluttering and heart thumping are very mild. Also the 18 hours includes at least 6 to 7 hours of virtually unbroken sleep.
I signed up here a few days back and almost immediately realised that many of those here suffer much more severe symptoms than I do.
I have probably experienced PVCs many times in the past without knowing just thinking it was all part of Afib.
Your comments on interpreting the ECG tracings interests me and I may well pursue this.
This is my first post here so not sure who I should be replying to! Since this thread seems to be partly about Kardia mobile I thought I'd post my own experience.
5 years ago I experienced an episode where my heart seemed to behave strangely and pulse felt very jumpy. After a second episode I went to GP who suggested buying a Kardia device and said I could email results to him. Next time I had an episode, I used the Kardia which showed "possible atrial fibrillation". Having emailed Kardia ECG to GP, he referred me to cardiologist, having passed on my own recorded results.
When I saw the cardiologist, he referred me for the usual tests- "proper" ECG, echocardiogram, 24 BP monitor and prescribed the usual AF meds - Apixiban and a beta blocker. However, I never went to hospital when I had an AF episode, so my diagnosis has only been on the basis of Kardia results and my doctors seem to be happy with that.
A point made by a poster upthread mentioned interference by vacuum cleaner. A couple of months ago, I had some problems getting readings with Kardia - messages suggesting interference. Moved it to different locations, and got a reading, but next time I tried, it wouldn't work properly, wherever I put it. I finally figured out that I needed to replace the battery! Now it works fine again.
@Magpie15, I am new to the site as well (10 days) and am also struggling with the protocols for responding.
I was in the same position as you and after seeing a cardiologist and loads of tests I was never in Afib when tested.
I then moved to a new area and got a Kardio monitor about the same time. My new GP saw the results and referred me to a cardiologist in the new area.
On the day of my appointment I had an Afib episode and was finally diagnosed. My new consultant told me though that he would have been quite happy to go with the Kardio results as it was fully FDA approved.
I have heard it is also NHS approved but that may have been a more recent development.
I have had mine about 4 years and it is still on the original batteries, but am glad you got yours sorted.
I was in Afib from 2:00 pm yesterday used 3 devices to test myself at 8:00 am this morning.
I was clear on my Kardio and Fitbit Charge 6 but my blood pressure cuff device showed an irregular heartbeat. The BP was also very low at 69/50 compared with 110/64 yesterday morning.
Subsequent BP readings did not indicate irregular heartbeat but were still low at 75/50.
I have though noticed that my BP does fall for a day or two after an Afib episode.
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. I have to go into the shade to try and read it if outside or near windows and even then often have to get my wife to look.
Heart rate smart watch
Heart rate monitor watch
Worse, more frequent bouts of Afib and much higher pulse rate while in Afib, advice please.
Decision time!
