Continuous AFib Monitoring Coming to Fitbit Watches Following FDA Approval

Fitbit owner Google this week came a step closer to rivaling the health features of Apple Watch after the FDA approved its new algorithm for continuously monitoring users' heart rate rhythms.

fitbit irregular heart rate notifications
Like Apple Watch, Fitbit devices with a heart-rate monitoring capability include an ECG app that must be manually run by the user to check for irregular rhythms, which can be a sign of atrial fibrillation (AFib), a potentially serious heart arrhythmia condition. AFib affects nearly 33.5 million people globally, and individuals with AFib have five times higher risk of stroke.

For several years, the Apple Watch has had one up on rival smartwatches by including an irregular rhythm notifications feature, which occasionally checks heart rhythm in the background and sends a notification if an irregular heart rhythm is identified that could potentially be atrial fibrillation (AFib). Upon receiving a notification, users can then launch the ECG app and perform a more comprehensive 30-second test by placing their finger on the Digital Crown to generate an ECG waveform.

Google's new PPG (photoplethysmography) algorithm works similarly by passively monitoring heart rhythm in the background overnight and whenever the user is resting, making for a potentially more capable life saver.

The clinical validation for Fitbit's PPG algorithm is supported by data from the landmark Fitbit Heart Study, which launched in 2020 and enrolled 455,699 participants over five months. The study was conducted entirely virtually during the pandemic, making it one of the largest remote studies of PPG-based software to date. Data presented at the 2021 American Heart Association Scientific Sessions found that the Fitbit PPG detections correctly identified AFib episodes 98% of the time, as confirmed by ECG patch monitors.

Google says the new PPG-based algorithm and Irregular Heart Rhythm Notifications feature will soon be available to consumers in the U.S. across a range of heart-rate enabled Fitbit devices.

Apple plans to further bolster the health smarts offered by Apple Watch this year, with a new body temperature monitoring sensor expected to feature in the Apple Watch Series 8. As part of watchOS 9, Apple is also planning to improve its existing atrial fibrillation detection feature with a new capability to measure how long a person is in a state of atrial fibrillation across a certain period.

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Top Rated Comments

Umacga Avatar
48 months ago

It didn't start out that way.

I've been using Fitbits for years. When google bought Fitbit, I was debating to "throw it away" and get an apple watch. I didn't and know google has my fitness data.
I’m an Apple guy through and through but despite having an Apple Watch 6, I find my older Fitbit far superior and use it most of the time instead. Much better heart monitoring, sleep monitoring, and battery life. Text/phone features are better on the Apple Watch but it’s way behind on everything else. AW was a big disappointment.
Score: 8 Votes (Like | Disagree)
jz0309 Avatar
48 months ago
competition is great, time for Apple to up its game on health sensors
Score: 6 Votes (Like | Disagree)
icanhazmac Avatar
48 months ago

Fitbit owner Google this week
Thanks but that is all I need to know to issue a hard pass.

While "competition" is good, I cannot believe that people let Google anywhere near their health related data.
Score: 5 Votes (Like | Disagree)
therunningman Avatar
48 months ago
I made the jump from FitBit to an Apple Watch over a year ago. The one thing that I REALLY miss is 24-7 heart rate monitoring. Constant heart rate monitoring potentially makes afib detection more accurate simply because there's more data there. I'm just not sure how useful the Apple Watch's alerts might be taking heart rate readings once every five to eight minutes.
Score: 5 Votes (Like | Disagree)
DeepIn2U Avatar
48 months ago

Interesting, I have the same reaction when I watch Battlefield Earth.
Because of Travolta or overall poor acting?
Score: 4 Votes (Like | Disagree)
I7guy Avatar
48 months ago

Thanks but that is all I need to know to issue a hard pass.

While "competition" is good, I cannot believe that people let Google anywhere near their health related data.
It didn't start out that way.

I've been using Fitbits for years. When google bought Fitbit, I was debating to "throw it away" and get an apple watch. I didn't and know google has my fitness data.
Score: 3 Votes (Like | Disagree)