Fitbit receives FDA clearance for algorithm to detect AF
The FDA has cleared Fitbit’s photoplethysmography-based algorithm to detect atrial fibrillation in wearers of its devices, the company announced.
The clearance was based on the results of the Fitbit Heart Study, the company stated in a press release.
As Healio previously reported, in the Fitbit Heart Study of 455,669 participants who were at least 22 years old, had a compatible Fitbit device (Ionic, Charge 3, Charge 4, Inspire HR or Inspire 2 trackers or Versa, Versa Lite, Versa 2, Versa 3 or Sense smartwatch), had an Android or iOS smartphone with the Fitbit app, and had no prior diagnosis of AF or atrial flutter, use of oral anticoagulation or implantation of a pacemaker or defibrillator, the positive predictive value of the algorithm for concurrent AF on the ECG patch monitor was 98.2%.
According to the release, the photoplethysmography-based algorithm enables long-term assessment that could enable identification of asymptomatic AF, while a spot-check approach with the company’s ECG app allows consumers to screen themselves for AF and share ECG traces with health care providers.
In a presentation at the American Heart Association Scientific Sessions in November, Steven Lubitz, MD, MPH, associate professor of medicine at Harvard Medical School and cardiac electrophysiologist at Massachusetts General Hospital, said the algorithm while the wearer is inactive continuously samples pulse data in 5-minute tachograms overlap by 50%, and flags an irregular heart rhythm if 11 consecutive tachograms are irregular.
In the Fitbit Heart Study, 1% of participants had an irregular heart rhythm detection, and 32.2% of participants with an irregular heart rhythm detection who submitted ECG readings had confirmed AF. Those with confirmed AF had a median AF burden of 7%.