Google has announced that the U.S. Food and Drug Administration has given official approval for new atrial fibrillation-detecting technology it will add to Fibit wearables.

The PPG (photoplethysmography) algorithm to identify atrial fibrillation (Afib) will be at the centre of Fitbit’s new Irregular Heart Rhythm Notifications feature.

Google explains: “Our new PPG AFib algorithm can passively assess your heart rhythm in the background while you’re still or asleep. If there’s anything that might be suggestive of AFib, you’ll be notified through our Irregular Heart Rhythm Notifications feature — allowing you to talk with your healthcare provider or seek further assessment to help prevent a significant medical event, such as stroke.

“When your heart beats, tiny blood vessels throughout your body expand and contract based on changes in blood volume. 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 analyses for irregularities and potential signs of atrial fibrillation.”

The feature will “soon be available to consumers in the U.S. across a range of heart-rate enabled devices”, according to Google. No doubt an international rollout will follow.