Fitbit’s latest AFib algorithm receives FDA clearance, will be available ‘soon’

Fitbit’s new algorithm for identifying signs of atrial fibrillation (AFib) has been cleared by the FDA.

The photoplethysmography (PPG) algorithm was designed to passively evaluate a user’s heart rhythm while they are still or sleeping.

“When your heart beats, tiny blood vessels throughout your body expand and contract based on changes in blood volume,” according to a new announcement from Google. “Fitbit’s PPG optical heart-rate sensor can detect these volume changes right from your wrist. These measurements determine your heart rhythm, which the detection algorithm then analyzes for irregularities and potential signs of AFib.”

The FDA’s decision was based in part on the Fitbit Heart Study, which focused on data from more than 455,000 patients. Lead author Steven A. Lubitz, MD, a cardiologist and cardiac electrophysiologist with Massachusetts General Hospital in Boston, and colleagues found that the Fitbit’s PPG detections were correct 98% of the time.

“These results show that wearables have the ability to identify undiagnosed atrial fibrillation with high reliability,” Lubitz said in November 2021, which he was presenting his team’s findings at the American Heart Association (AHA) Scientific Sessions in 2021. “Since so many consumers use wearables, it is possible that algorithms such as the one we studied could be applied widely to help identify undiagnosed atrial fibrillation, allowing patients to obtain care before devastating complications such as a disabling stroke may occur.”

According to the Google announcement, this newly approved algorithm will soon be available “across a range of heart-rate enabled devices.” This will give Fitbit users two ways to detect AFib — proactive screening using the company’s electrocardiogram application and passive screening thanks to PPG screening.

“We want to make AFib detection as accessible as possible to help reduce the risk of potentially life-threatening events, like stroke, and ultimately improve overall heart health for everyone,” the company said.  

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Michael Walter
Michael Walter, Managing Editor

Michael has more than 18 years of experience as a professional writer and editor. He has written at length about cardiology, radiology, artificial intelligence and other key healthcare topics.

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