New Apple Watch ECG Algorithm Version Included in iOS 14.3 and watchOS 7.2

Apple has designed a new algorithm that Apple Watch uses to measure electrocardiogram (ECG) waves, according to developer documentation for the iOS 14.3 and watchOS 7.2 betas.

apple watch ecg
In the official documentation, a new "version 2 algorithm" declaration has been added. No other information is included.

The ECG feature includes irregular heart rhythm detection, which intermittently measures the user's heart rate in the background and sends a notification if it detects an anomaly it categorizes as atrial fibrillation, which can be a serious heart arrhythmia condition.

Based on beta code uncovered by MacRumors, it's likely that the new algorithm will allow the ECG app to check for atrial fibrillation (AFib) at higher heart rates - during exercise, for example.

ecg algorithm version 2
iOS 14.3 will introduce support for Apple Fitness+, Apple's upcoming fitness service that will work with the Apple Watch, plus it brings a new Cardio Fitness feature that lets you know if your VO2Max levels are low. VO2Max is a useful measurement of overall fitness and heart health.

iOS 14.3 is set to be released on Monday, December 14, which is also the day that Apple Fitness+ is coming out.

(Thanks, Simon!)

Related Forum: Apple Watch

Top Rated Comments

jambon Avatar
12 months ago
In the Health app on the phone, it now states that ECG is available/better at higher/lower HRs
Score: 8 Votes (Like | Disagree)
hellosil Avatar
12 months ago
I love how tech like this can make our health better.
Score: 7 Votes (Like | Disagree)
tx368 Avatar
12 months ago
And ECG is finally rolling out to Taiwan in this update!
Score: 5 Votes (Like | Disagree)
neuropsychguy Avatar
12 months ago

Wait what? The ECG only works when your finger is on the Digital Crown. It can’t work in the background.
The background irregular heart rhythm detection does not use the ECG but it is grouped with the ECG features (which is technically inaccurate but they are related features, just different technologies). It's been around as long as the ECG: "Using the optical heart sensor in Apple Watch Series 1 or later, the irregular rhythm notification feature will occasionally check the user’s heart rhythm in the background for signs of an irregular heart rhythm that appears to be AFib and alerts the user with a notification if an irregular rhythm is detected on five rhythm checks over a minimum of 65 minutes." (https://www.apple.com/newsroom/2018/12/ecg-app-and-irregular-heart-rhythm-notification-available-today-on-apple-watch/)
Score: 3 Votes (Like | Disagree)
tx368 Avatar
12 months ago

Still waiting for ECG in Japan!
Any news about it?
Since ECG received final medical approval in Japan this September, I guess maybe iOS 14.3 will cover ECG functionality also Japan as well? *finger-crossed*
Score: 2 Votes (Like | Disagree)
smbutton Avatar
8 months ago
Well it appears the TGA has approved this for Australia. Can't wait for the update to include this function.
Score: 2 Votes (Like | Disagree)

Related Stories

heart analyzer watch

Heart Analyzer App Gains Blood Oxygen Complication for Apple Watch Series 6

Tuesday November 10, 2020 3:27 am PST by
Heart Analyzer today reached version 8.3, bringing some notable improvements to the popular heart health app including new complications and customizations. Top of the list for Apple Watch Series 6 owners will be the new Blood Oxygen Saturation complication, which lets you track the SPO2 metric over the past week with a glance of your watch face. There's also a new complication that shows ...
watchos 7 cardio fitness 1

watchOS 7.2 and iOS 14.3 Add Cardio Fitness Notifications

Monday December 14, 2020 10:46 am PST by
Today's watchOS 7.2 and iOS 14.3 updates introduce a new cardio fitness feature that's designed to let users determine their cardio fitness level and receive notifications on the Apple Watch if it falls into a low range. Apple says that "breakthrough technology" in watchOS 7 lets the Apple Watch determine cardiorespiratory fitness as measured by VO2 max. VO2 max is the maximum amount of...
7

Apple Releases watchOS 7.4 With iPhone Unlocking, Apple Fitness+ AirPlay 2 Support

Monday April 26, 2021 9:57 am PDT by
Apple today released watchOS 7.4, the fourth major update to the watchOS 7 operating system that was released in September 2020. watchOS 7.4 comes three months after watchOS 7.3, an update that introduced a new watch face, a Time to Walk feature, and expanded ECG availability. ‌‌The watchOS 7.4 update‌‌ can be downloaded for free through the dedicated Apple Watch app on the iPhone by ...
apple heart health month lori and bob 02032021 big

Apple Watch Alerts Man to Heart Condition in Yet Another Potentially Life-Saving Story

Thursday February 4, 2021 8:08 am PST by
February is American Heart Month, and Apple marked the occasion today with a Newsroom feature highlighting how the Apple Watch potentially saved the life of 59-year-old Bob March. In short, the Apple Watch alerted March to irregular heart rate readings that ultimately led to doctors discovering that he had arrhythmia. Bob and Lori March Bob was gifted the Apple Watch by his wife Lori for...
7

Apple Releases watchOS 7.5 With Apple Card Family and Subscription Podcast Support

Monday May 24, 2021 10:07 am PDT by
Apple today released watchOS 7.5, the fifth major update to the watchOS 7 operating system that was released in September 2020. watchOS 7.5 comes one month after the release of watchOS 7.4, an update that added Apple Watch iPhone unlocking and other features. ‌‌The watchOS 7.5 update‌‌ can be downloaded for free through the dedicated Apple Watch app on the iPhone by going to General >...
Kardia Band apple watch

AliveCor Files Antitrust Suit Against Apple for Preventing Third-Party Irregular Heart Rhythm Analysis on Apple Watch

Wednesday May 26, 2021 10:34 am PDT by
AliveCor, a company that that has developed an ECG 'KardiaBand' for the Apple Watch, today filed an antitrust lawsuit against Apple that accuses the Cupertino company of "monopolistic conduct." According to AliveCor, Apple's decision to exclude third-party heart rate analysis providers from the Apple Watch has harmed AliveCor and impacted patients and consumers. To go along with the...
apple watch ecg

Apple Touts Next Week's Launch of Apple Watch ECG Feature in Taiwan

Thursday December 10, 2020 2:39 am PST by
Apple is touting next week's launch of its Apple Watch electrocardiogram (ECG) feature in Taiwan, following the upcoming release of watchOS 7.2 and iOS 14.3. In a newsroom update on its regional Taiwanese website, Apple says the ECG app on Apple Watch Series 4 and subsequent models will be launched in Taiwan via iOS 14.3 and watchOS 7.2 from Tuesday, December 15, Taiwan time. The ECG...
applewatchse

Apple Seeds watchOS 7.5 Release Candidate to Developers

Monday May 17, 2021 10:08 am PDT by
Apple today seeded the release candidate version of an upcoming watchOS 7.5 update to developers for testing purposes, with the new beta approximately a week after the release of the third beta. To install the ‌watchOS 7.5 beta, developers need to download the proper configuration profile from the Apple Developer Center. Once the profile is in place, the watchOS 7.5 beta can be downloaded...
apple watch ecg wrist

Apple Watch Irregular Heart Rhythm Notifications Approved in Australia as ECG Approval Edges Closer

Monday February 8, 2021 6:16 am PST by
The Apple Watch's irregular heart rhythm notifications have been approved in Australia, indicating that approval for the ECG feature may be soon to follow after years of waiting, according to EFTM. Documents seen by EFTM from Australia's Therapeutic Goods Administration show that the Apple Watch's irregular rhythm notifications feature has now been approved and added to the Australian...
apple watch ecg wrist

Apple Watch ECG Feature Gets Approved in Australia

Wednesday March 3, 2021 2:07 am PST by
The Australian government has approved ECG functionality on the Apple Watch, giving Apple the all-clear to launch the feature for Apple Watch users in the country, according to a regulatory document first spotted by The 8-Bit. Earlier last month, the Apple Watch's irregular heart rhythm notification received approval in Australia, although ECG did not. Irregular heart rhythm is a feature...