Monitoring Afib

My initial Forum post! Also relatively new to Afib (Cariologist diagnosed, but asymptomatic and did not even know the term ~ 3yrs back).

It has rather startled me reading this forum's posts: Most of you "know" your Afib episodes so well (number, duration, history.... apparently
mainly from symptoms)! OTOH I never have had obvious symptoms. I have been a "push the limit" endurance athelete (mountaineering, cycling),
so I know what max HR feels like, but always consistent with the effort and rapid settle down. My Afib was detected only by chance routine doctor office visit, then followed thru with stress tests, ECGs, Holter, etc. However, even now: I never know: in/out of Afib? Even to the extent that I often wonder whether the entire diagnose is an "illusion".

But, evidently not an illusion. I have come to start monitoring my HR, 24/7. I have excellent quiescent HR (<100, and quite low, resting <50-60, with no episodes of spontaneous high excursions). However when I exercise (daily run, swim, cycle) I have found (now-a-days, at least. In my pre-Afib days I never monitored), only moderately high exertion will push HR>200. It comes immediately down, but NOT GOOD. Addressing this, my cardiologist has me on Metoprolol, which indeed does keep a lid on exertion HR (< 140).

So, not wanting to live in this limbo and being otherwise healthy (CHADS-VASc score 1), I'm actively looking to ablate. My question to y'all is how to best casually monitor continuously to accurately identify when one is in Afib? HR tracking itself just doesn't seem to do that. I know that many of you [highly] recommend the Kardia. But, since I am asymptomatic that only allows me to randomly check, few times a day. Also with Kardia I cant see how it's inherently low Res. (2 lead) ECG can truely identify Afib. I it just presumed from heart beat irregularity?

I find it very interesting how others feel their afib (or not). When I had an episode, feeling my pulse was like a car driving rapidly down a rocky bumpy road - very fast and erratic - 180 bpm (down to 80-90 when on meds). Normal in the 50's. How can one not tell the difference? I have always been quite fit, with no noticeable issues when in afib, other than having to breath more rapidly if going up stairs quickly or exercising. I didn't try to exercise when in afib because I couldn't accomplish much with 02 debt coming on so quickly. Ablated 12 years ago successfully.

Get the Kardia. It will correctly diagnose AF (it calls it "possible AF", but that means AF). Skip the subscription service and the paid analysis stuff. In that case it won't store old rhythm strips but if you want to keep one just email it to yourself right away or print it. If you have specific questions about one you can then get it to your cardiologist or, if it's not urgent and you want our opinion(s), you can post it here if you feel comfortable doing so. There are several regular posters here who can offer insight (caveat being we're not doctors and we don't play them on the internet so take any advice you get as that of a layperson).

The good folks at Kardia aren't going to tell us exactly how their device works. That's their "bread and butter" so to speak. But if I had to guess I'd say it does some math on the R-R interval (time between the big "spikes" on the EKG). Whether that's an FFT or autocorrelation or something else, I really don't know. But it works and the FDA agrees.

Quote
IDbill
Also with Kardia I cant see how it's inherently low Res. (2 lead) ECG can truely identify Afib. I it just presumed from heart beat irregularity?

I'm not sure what the Kardia algorithm is, but I can say it does work for me.

One hallmark of afib is a highly variable R to R distance on an ECG. This stands out easily on an r to r recording heart rate monitor. When I first started monitoring 14 years ago, I used a Polar S810 (and S810i) monitor. Very few monitors will actually record each beat length in ms (milliseconds). This does not display beat to beat in real time. You need to record and then download to a computer to view. Today, to accomplish the same thing (which I don't do regularly as my remission program works such that I'm rarely out of rhythm) I use an app - Heart Rate Variability Logger. It will record using a Polar H10 strap. I can look at the data on my computer as the app will download via a Dropbox Account on the phone & computer. It exports a number of files. I use the RR_Kubios.txt file which outputs the data in ms:

992
970
881
839
799
786
795
792
876
927
880
852
877
823
830

You could suck into Excel and convert each value to BPM - 60,000/rrtime = BPM and plot.

I use the ancient Polar Precision Performance Software v4 to view the data. An updated version is here <[support.polar.com] but I've not used the newer version.

I create an .HRM file by appending data from the Kubios file after the [HRData] to this and save as a .HRM

[Params]
Version=106
Monitor=37
SMode=000000000
Date=20131023
StartTime=17:00:56.0
Length=01:05:20.9
Interval=238
Upper1=0
Lower1=0
Upper2=0
Lower2=0
Upper3=0
Lower3=0
Timer1=00:00:00.0
Timer2=00:00:00.0
Timer3=00:00:00.0
ActiveLimit=0
MaxHR=160
RestHR=40
StartDelay=279
VO2max=50
Weight=64

[Note]


[Summary-123]
3920 0 3920 0 0 0
160 0 0 40
0 0 0 0 0 0
160 0 0 40
0 0 0 0 0 0
160 0 0 40
0 6101

[Summary-TH]
3920 0 3920 0 0 0
160 0 0 40
0 6101

[HRZones]
160
145
130
115
95
80
0
0
0
0
0

[SwapTimes]

[HRData]


I then use the File;Open HR file to open the HR file.

I use 20-30 minute windows to look at the data. Afib stands out like a sore thumb. You can see examples for interpretation in the two documents linked here <[www.afibbers.org]

You can monitor for many hours if you like.

I can also use a phone app that uses the light & camera as a plesmograph. You can visually see the peaks in the heart beat wave form. If they are not regular, you are in afib. You can do the same thing with your finger on your radial pulse (I can name that rhythm in 4 beats or less...).

One app that will do this is CameraHRV. This is not for long term monitoring.

In addition to the rr distance being irregular, my waveform has a highly variable amplitude and character (can feel this in the radial pulse, too).

On any app, I turn off any smoothing or error correction. You are looking for the anomalies.

My path to afib, 14 years ago was also chronic fitness with low resting HR. One of the parts of my afib remission program is detraining from endurance fitness, though I remain fit. In my case, the product of intensity times duration is the trigger. High intensity, short duration is OK, long duration low intensity is OK, long duration high intensity is not OK, a trigger. <[www.afibbers.org]

George

Isn't another critical factor to see if a P wave is before every QRS (assuming no ablations happened)?

Few months ago i had a virus and my HR was irregular. GP thought i was in AF. To confirm she took a 10 lead EKG and she did say that i was in AF (irregular R -R) bu i saw a P wave before every QRS.
Turned out that the cardiologist looking at it agreed with me. The GP called me that afternoon telling me that i don't need to take an anticoagulant (I did anyway for a few days)

Quote
Joe
Isn't another critical factor to see if a P wave is before every QRS (assuming no ablations happened)?

When I sample with my Kardia, I hold one lead with my right hand and put the other on my lower left side - lower abdomen, hip or knee as this has a presentation with a more pronounced P wave.

I find a tachogram (heart rate vs. time graph) which is what I get from the r to r recordings on a heart rate monitor (and some Holter's will do this, too) as a very useful presentation. Most doc's aren't used to looking at it, though it is done in research settings. I recall trying to show one to my mother's doc and he was having a hard time understanding what he was looking at. Afib on a tachogram looks like a seismogram in an earthquake.

For the OP, there are also Holters made in China available on eBay. Years ago I borrowed one from a doc friend. For my purposes, I found I got the info I needed from a tachogram with a lot less hassle than the Holter. There have been some members over the years here who've gotten their own Holters.

George

Another option if you like the tech and you are an iPhone person is an Apple Watch. Yes, the newest ones run a similar ECG to the Kardia, but even at least back to the series 2 models will constantly monitor HRV. I found that when I am out of rhythm, my recorded heart rate variability spikes above 150.

I’m not really sure how the watch interacts with Android phones if at all. For the iPhone, all the data including ECG’s are stored in the Apple health app.

Try the simple way first, feel your Pulse. NSR is regular, and AFIB is Irregular. Sometimes you have to feel for over 10 seconds though if your AFIB Heart Beats are relatively even. If you can get a device like the Kardia, then you can feel your Pulse when the Kardia indicates AFIB. That way you will learn how to feel it on your own.

Yes, I have much attempted to discern the "regularity" of my felt pulse. Trouble is, its too subjective (to me): I had never ventured to feel my pulse before sometime last year, so I have no relative sense of NSR. My cardiologists always suggests "just feel your pulse!", but his judgement is based on decades of experience. So, coaching from a Kardia seems a great route. However, even with the Kardia I'd feel (as a beginner) much more confident in judging my being in Afib if there were available some typical Kardia Afib examples. That is, as a template to know that any irregularity I see in my own traces (there is always some, right?) measures up to what is considered bone fide Afib.

Anyway, what I think I'm finding in my quiescent felt pulse (e.g. sitting still as I'm typing now) is a sensibly regular rate, 50-60/Min. with NO faster bursts, but several times/Min. of gaps (where the next anticipated beat just doesnt occur, or is so much weaker that I cant be sure one occured). So, yes, its "irregular" but not in the way I see most posts describing (at least momentary, much faster rate episodes).

Given that consensus measure of Afib seems to be beat irregularity (R-R), will some of the other available "2 lead" ECG monitors (Emay, FL10, Comtec, Pulsebit Mate, snapEKG, etc) do adequately? Only reason for not immediately going with Kardia is that I dont happen to have a compatable portable device, and would prefer to connect just to a computer.

Hmm, i've got the same, normal HR but quite a few seemingly missing beats in between. I think it's PACs? I stopped being overly concerned about them since i've got a mild virus and i think that's a problem for heart rhythm?
I take 5mg Eliquis and 50mg Flec2x/day and hope things will settle again.
Monitoring would not help me unless i get a proper graph. Anyway, as far as i'm concerned, a normal HR/min is helpful?

IDbill:

That certainly sounds like PAC's (Premature Atrial Contractions). That is not AFIB. If your ever getting an EKG done, that would also be a good time to feel your Pulse, as the EKG would be certain correct feedback or your status.

GeorgeN, thanks for the details & scripts. If I have the time I would love to write my own algorithms for analyzing R-R data (that was my field !). However was hoping to just run with existing, turnkey stuff. I'm a bit hesitant to firmly conclude my condition from a Kardia proprietary "Afib oracle". Would rather see my actual ECG peak pattern and be able to verify its likeness to know, typical Afib traces. Are there such? For the purpose of simple basic ECG peak plotting there seem to be a growing competition to Kardia: FL10, Emay, snapEKG, Contec, Pulsebit Mate..... any opinions on those (attractive to me for their alternate computer connects?

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GeorgeN

I find a tachogram (heart rate vs. time graph) which is what I get from the r to r recordings on a heart rate monitor (and some Holter's will do this, too) as a very useful presentation.

Would you describe exactly what a tachogram is? For instance I have used Polar sensors which provide (e.g. plot) HR at each of a precise sequence of time intervals (e.g. 2 Sec.), thus generating your "tachogram" (heart rate vs time graph). Seems the generic term for this is "HR tracking", but I have always wondered how this is generated from the raw data (the sequence of time intervals between pulses).

Lots of interesting informations about one lead ECG devices on
this website.

In the same vein as Pompon's link: <[a-fib.com]

Anyone have opinion on the new one coming out? $149.00 6 wire lead. Does anyone know if VA uses or supplies these?