Fitbit and Pacemaker effect

[Buzzweizer]

Does a pacemaker affect sleep scores and ECG. After the pace maker my REM and deep sleep are almost non-existent. ECG will not complete the 39 second cycle. Resets after 4 to 5 seconds 

[JohnnyRow]

Pacemaker and Sense 2 here.  No problem with ECG.  I expect you meant 30 second cycle, not 39 second,as it measures for 30 seconds.
As for sleep, I'm getting plenty of deep sleep measured, though not much REM, though I do remember dreaming. But got  my pacemaker nearly year ago and don't remember if that used to be the case, and if it changed after pacemaker.  I've been assuming that has nothing to do with pacemaker since I haven't seen it affect anything else except my 'sleeping heart rate' always being right at bottom level set for my pacemaker.

Moderator edit - formatting

[LZeeW · Accepted solution]

Hello @Buzzweizer and welcome to the Community.  A pacemaker will absolutely affect all the things you mention.  I'm not sure why the ECG doesn't complete the cycle.  But that is irrelevant.  Even if it completed the cycle, your results will always be inconclusive.  The ECG is programmed to look for normal sinus rhythm or atrial fibrillation or inconclusive.  The ECG app is explicitly not intended for people with pacemakers.

 With respect to sleep stages, Fitbit has an algorithm that uses breathing rate and HRV (among other things) to estimate sleep stages.  There is a subtle change in your beat-to-beat heart rate when you inhale and exhale.  You need a mostly normal rhythm to get sleep stages.  It will depend on how much of the "work" is done by your pacemaker.

[Buzzweizer]

Thanks. All makes sense