Huge study confirms Apple Watch ECG accurately detects AFib

Huge study confirms Apple Watch ECG accurately detects AFib


Apple Watch Meidcare
Doctors found that if your Apple Watch ECG indicates you have a heart problem, you almost certainly do.
Photo: Apple

The electrocardiogram built into recent Apple Watch models isn’t likely to give wearers false notifications that they have atrial fibrillation, a potentially dangerous heart condition. A clean bill of health for this wearable’s ECG is the conclusion of a study involving over 400,000 participants that was published in the New England Journal of Medicine.

Looking for false positives in the Apple Watch ECG

Last year, when the Apple Watch Series 4 became this company’s first wearable with an ECG, some in the medical community expressed concern that many, many wearers would be incorrectly told they had atrial fibrillation, both frightening them and crowding doctors offices with patients who didn’t need to be there.

The point of the Apple Heart Study was to see whether these concerns are justified.

Apple Heart Study methods

Of 419,297 people in the eight-month study, 2161 were notified that they had AFib by their Apple Watch ECG. That’s about half a percent of the participants.

This sub-group was sent ECG patches to get a second opinion. These confirmed that 84% of these people had symptoms concordant with atrial fibrillation, and 34% had the heart condition.

From this data, the doctors who conducted this study determined that “The probability of receiving an irregular pulse notification was low.” Even so, they say the Apple Heart Study is merely a foundation for follow-up studies to get additional data.

Most notably, the study wasn’t looking to see how many people wearing Apple’s wrist computer have AFib without the wearable detecting it.

In the mean time, they’re found that if your Apple Watch ECG says you have AFib, go to a doctor. There’s almost certainly something wrong with your heart.

Source: New England Journal of Medicine


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