alerts about atrial fibrillation

[Chimel]

I have a question about the notifications I receive from my Fitbit. I get alerts about atrial fibrillation with a heart rate that varies from 48 to 178 BPM over a period of 5 hours. These notifications are listed under "Irregular Heart Rhythm Notifications." However, when I check the heart rate data for the entire day, I don't see any abnormalities in the heart rate measurements; the graph appears normal.

I am not experiencing any symptoms of atrial fibrillation and am starting to suspect that my Fitbit is issuing these notifications incorrectly.

Is this phenomenon explainable? Has anyone had similar experiences or tips for improving the accuracy of heart rate measurements? According to Fitbit's information, false notifications can be caused by factors such as sensor placement or motion artifacts. Additionally, it's possible that the device's algorithms may sometimes yield false-positive results.

I appreciate any insights and experiences you can share!

[LZeeW]

Hello @Chimel and welcome to the Community.  The daily heart rate graph show a number that is averaged over five minutes.  The irregular rhythm notification algorithm looks at your heart rate on a beat-to-beat basis.  Beat-to-beat measurements are measured in milliseconds.

If you have received several notifications, you should see your health care provider as soon as possible.

[Chimel]

@LZeeW,

Thank you for your response. I understand your point. However, I would expect to see heart fibrillations occurring over a period of 5 hours reflected somewhere in the daily heart chart. I would expect there to be at least a 5-minute interval with a value that significantly deviates from the normal range.

There is currently a medical investigation ongoing, but it has not yet led to a cause. The doctor is questioning the accuracy of the Fitbit readings, which is why I raised the question.

[LZeeW]

@Chimel   I participated in the Fitbit Heart Study that developed this feature.  Fitbit reported its findings in a major medical journal.  If a participant received a notification, they were offered a home ECG monitoring patch.  The data from both was compared and the Fitbit notification was correct 98.2% of the time.

My background is physiology and biomedical engineering.  I jumped at the chance to participate in the Heart Study.  This feature is FDA approved and I don't think your doctor should question the accuracy of this feature.