In addition to calculating the Heart Rate Variability (Apple uses the 1 standard deviation of a series of consecutively measured R-R intervals) , the watch also calculates a weekly AFIB burden (time spent in AFIB over the previous 7 days). Presumably the input for the AFIB burden is some level of heart rate variability, above which the watch considers the wearer to be in AFIB. Does anyone know what that level - or threshold - is? (for example... Is it above 35 ms or above 50 ms or above 75ms? . Apple engineers are unwilling to divulge, citing proprietary algorithm. So the only way to answer is question is with empirical data, that is, by users experience https://www.afibbers.org/forum/read.php?9,197782,197782#msg-197782 Mon, 21 Sep 2026 21:02:42 +0000 Phorum 5.2.23 https://www.afibbers.org/forum/read.php?9,197782,197795#msg-197795 https://www.afibbers.org/forum/read.php?9,197782,197795#msg-197795 The EP was satisfied that we could monitor the burden (on a weekly basis) using the apple watch - however if he were to recommend a procedure that was covered by insurance he would have to have ZIO data to comply with the insurance criterion. OTOH, he was satisfied that he could use the Apple calculated burden to guide him in modifying prescriptions.

Perhaps we were fortunate that the RVR never exceeded ~ 140 BPM or so. I agree with Cary that the reliability of R-R intervals degrades at very high ventricular rates.]]> Searching9 AFIBBERS FORUM Mon, 04 Nov 2024 14:29:52 +0000 https://www.afibbers.org/forum/read.php?9,197782,197793#msg-197793 https://www.afibbers.org/forum/read.php?9,197782,197793#msg-197793 here, the first is NSR with lots of PACs, the second is afib. Both would have had very high HRV. I would also be suspect of the accuracy using plethysmography vs ECG data for this. I believe when you have to touch the watch with your other hand is ECG data, otherwise the watch is using plethysmography (blood flow pulses) for the afib data.]]> GeorgeN AFIBBERS FORUM Mon, 04 Nov 2024 12:19:43 +0000 https://www.afibbers.org/forum/read.php?9,197782,197790#msg-197790 https://www.afibbers.org/forum/read.php?9,197782,197790#msg-197790
If you have a PM, you could get an interrogation upload because it’s more accurate]]> susan.d AFIBBERS FORUM Mon, 04 Nov 2024 10:10:37 +0000 https://www.afibbers.org/forum/read.php?9,197782,197785#msg-197785 https://www.afibbers.org/forum/read.php?9,197782,197785#msg-197785 not referring to the interpretation of AFIB from an ECG on the apple watch. Rather (it would seem) that the AFIB burden is calculated independently of the ECG.
It would appear that the Heart rate variability is the major (and perhaps only) input used to formulate an AFIB history. Hence my question, when is a HRV observation flagged as AFIB (for purposes of aggregating weeks-long data to produce an AFIB burden)]]> Searching9 AFIBBERS FORUM Mon, 04 Nov 2024 04:23:38 +0000 https://www.afibbers.org/forum/read.php?9,197782,197783#msg-197783 https://www.afibbers.org/forum/read.php?9,197782,197783#msg-197783 Carey AFIBBERS FORUM Mon, 04 Nov 2024 04:08:18 +0000 https://www.afibbers.org/forum/read.php?9,197782,197782#msg-197782 https://www.afibbers.org/forum/read.php?9,197782,197782#msg-197782
Presumably the input for the AFIB burden is some level of heart rate variability, above which the watch considers the wearer to be in AFIB.

Does anyone know what that level - or threshold - is?

(for example... Is it above 35 ms or above 50 ms or above 75ms? . Apple engineers are unwilling to divulge, citing proprietary algorithm. So the only way to answer is question is with empirical data, that is, by users experience]]> Searching9 AFIBBERS FORUM Mon, 04 Nov 2024 03:59:26 +0000