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Apple Says watchOS 5.1.2 Coming Today With ECG App Enabled on Apple Watch Series 4

Apple has announced that watchOS 5.1.2 will be publicly released today and will enable the long-awaited ECG app on Apple Watch Series 4 models in the United States. The update will also enable irregular heart rhythm notifications on Apple Watch Series 1, Series 2, Series 3, and Series 4 models.


watchOS 5.1.2 should be available through the Apple Watch app on a paired iPhone around 10:00 a.m. Pacific Time as usual.

Apple's COO and Apple Watch team head Jeff Williams:
Apple Watch has helped so many people around the world and we are humbled that it has become such an important part of our customers' lives. With the release of these heart features, Apple Watch takes the next step in empowering people with more information about their health.
Last week, MacRumors was first to report that watchOS 5.1.2 will enable the ECG app on Apple Watch Series 4 models, based on an internal Apple Store training document. ECG data will be available in the Health app and exportable via PDF on an iPhone 5s or newer, after updating to iOS 12.1.1 released yesterday.

watchOS 5.1.2 will feature an Apple-designed ECG app that can indicate whether your heart rhythm shows signs of atrial fibrillation, a serious form of irregular heart rhythm, or a normal sinus rhythm. This is possible thanks to new electrodes built into the back crystal and Digital Crown on Series 4 models.

Apple Watch Series 4 is capable of generating an ECG similar to a single-lead electrocardiogram, according to the FDA. Both the ECG app and irregular heart rhythm notifications are regulated features that have received De Novo classification from the FDA, making them available over the counter.

The ECG app will check heart rhythm every few hours or so, and if there are five consecutive readings that appear to be abnormal, the Apple Watch will alert the user to see a doctor. As for notifications, users will be alerted if an irregular heart rhythm is detected on five checks over a minimum of 65 minutes.

Importantly, in an internal document obtained by MacRumors, Apple cautioned that the ECG app is "not intended to be a diagnostic device or to replace traditional methods of diagnosis," and "should not be used to monitor or track disease state or change medication without first talking to a doctor."

To take an ECG reading from the Apple Watch, users will need to place a finger on the Digital Crown while wearing the watch. The reading is completed in 30 seconds, allowing users to determine whether their hearts are beating in a regular pattern or if there are signs of atrial fibrillation.

Apple says the ECG app's accuracy was validated in a clinical trial of around 600 participants in the United States:
Rhythm classification from a gold standard 12-lead ECG by a cardiologist was compared to the rhythm classification of a simultaneously collected ECG from the ECG app. The study found the ECG app on Apple Watch demonstrated 98.3 percent sensitivity in classifying AFib and 99.6 percent specificity in classifying sinus rhythm in classifiable recordings. In the study, 87.8 percent of recordings could be classified by the ECG app.
Apple is making good on its promise of making the ECG app available by year's end. watchOS 5.1.2 has been in beta testing since November 7, but the ECG app was nowhere to be found during the pre-release period.

Apple says the setup process for these heart health features will include details about who can use the features, what the features can and cannot do, what results users may get and how to interpret them, and instructions for what to do if users are feeling symptoms that require immediate medical attention.

Related Roundups: Apple Watch, watchOS 5
Tag: ECG
Buyer's Guide: Apple Watch (Buy Now)


Top Rated Comments

(View all)

5 days ago at 05:12 am
And 99% of users will try it once, find out their heart is normal and never touch it again, despite vehemently demanding it every day for the past 2 months.
Rating: 15 Votes
5 days ago at 05:07 am

Fingers crossed. :rolleyes:


Not sure it will work correctly if you keep your fingers crossed ;)
Rating: 9 Votes
5 days ago at 05:17 am

And 99% of users will try it once, find out their heart is normal and never touch it again.

True... Statistically, the percentage of people who don't have any heart rhythm issues is more like 95%. However, for that remaining 5%, including my wife who has SVT, it is literally a potential life saver!
Rating: 8 Votes
5 days ago at 05:22 am

so, do i have to permanently (until it comes to UK/EU) move my AppleID to US to make ECG work properly?


It should be approved in the EU/UK by around 2053, just in time for the iPhone 28s & Apple Watch 19.
Rating: 7 Votes
5 days ago at 04:58 am
I’m infinitely curious how well or not well this works, since Apple software quality control (in general not just the watch) has taken a serious nosedive in the past several years

5.1 bricked watches! 5.1.1 fixed it supposedly, and now 5.1.2 will be in control of your ECG monitoring. That’s quite the progression
Rating: 6 Votes
5 days ago at 05:25 am

And 99% of users will try it once, find out their heart is normal and never touch it again, despite vehemently demanding it every day for the past 2 months.


Irregular heart rhythm notifications will also be enabled in watchOS 5.1.2 on Series 1 through Series 4.

Hopefully less than 1% of users need this feature as well, but it will be a passive feature that doesn't require anything besides wearing the watch.
Rating: 6 Votes
5 days ago at 05:17 am
more excited for the essential infograph complications coming in 5.1.2
Rating: 5 Votes
5 days ago at 06:53 am

so, do i have to permanently (until it comes to UK/EU) move my AppleID to US to make ECG work properly?

Because you people drive on the other side of the road Apple need more time to reverse all the waveforms ;-).
Rating: 5 Votes
5 days ago at 05:27 am
I'm actually looking forward to having basic complications available on the series 4 more than the ECG.
Rating: 3 Votes
5 days ago at 07:56 am
Turning the world into hypochondriacs one person at a time.
It's real folly to play your own cardiologist, you're going to drive yourself nuts.
Say goodbye to your peace of mind.
Rating: 2 Votes

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