Apple watch may detect AFib: StudyMay 8, 2019
An Apple Watch may be able to detect heart rhythm changes that subsequent medical tests confirm to be atrial fibrillation, says a new study.
AFib is often undiagnosed since it might not cause noticeable symptoms, but it contributes to 1,30,000 deaths and 7,50,000 hospitalizations in the US each year.
Results from the Apple-funded study presented recently, at the American College of Cardiology Scientific Session in New Orleans, indicate that the wearable technology can safely identify heart rate irregularities.
The virtual study with over 4,00,000 enrolled participants to determine whether a mobile app that uses data from a heart-rate pulse sensor on the Apple Watch can identify atrial fibrillation. The condition often remains undetected.
Participants had both an iPhone and an Apple Watch. A special app checked each participant’s heart-rate pulse sensor for an irregular pulse, intermittently. The participant would receive a notification and was asked to schedule a telemedicine consultation with a study doctor. Then the participant would be sent ambulatory ECG patches to record the rhythm of their heart for up to a week.
Overall, only 0.5 percent of participants received irregular pulse notifications, an important finding given concerns about potential over-notification. Comparisons between irregular pulse-detection on Apple Watch and simultaneous electrocardiography patch recordings showed the pulse detection algorithm has a 71 percent positive predictive value.
Eighty-four percent of the time, participants who received irregular pulse notifications were found to be in atrial fibrillation at the time of the notification. 34 percent of the participants who received irregular pulse notifications and followed up by using an ECG patch over a week later were found to have atrial fibrillation. Since atrial fibrillation is an intermittent condition, it’s not surprising for it to go undetected in subsequent ECG patch monitoring.
Fifty-seven percent of those who received irregular pulse notifications sought medical attention.