Electrocardiogram Functionality in New Apple Watch Series 4 Models Limited to US, Coming Later This Year

Apple Watch Series 4 models include an electrical heart rate sensor that's designed to take an electrocardiogram (ECG) using an ECG app, the built-in sensor, and the electrodes included in the Digital Crown, but the ECG functionality won't be coming until later this year.

According to Apple's Apple Watch Series 4 website, the ECG app that will enable the electrocardiogram feature will be available later in 2018. That means at launch, the ECG feature won't be functional.

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As several MacRumors readers have pointed out, it appears ECG readings are going to be limited to Apple Watch models sold in the United States. Apple Watch Series 4 pages for countries like the UK and Canada contain no mention of the feature, and Apple's press release for Series 4 models says ECG functionality is U.S. only.

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 just 30 seconds, allowing users to determine whether their hearts are beating in a regular pattern or if there are signs of atrial fibrillation, which can be an indicator of serious health problems.

Atrial fibrillation is a health condition that often goes undiagnosed, so the ECG feature in the Apple Watch will be highly useful for detecting early signs of disease. ECG readings also normally require a full ECG machine and a visit to the doctor, which is far less convenient than a reading taken with the Apple Watch.

Apple says that the ECG feature in the Apple Watch has been granted a De Novo classification by the FDA as outlined on the FDA's website [PDF], and the need for regulatory approval is likely why the ECG feature is not available in other countries.

De Novo FDA approval is a preliminary approval process granted to new devices that are not likely to cause harm. According to the FDA, the Apple Watch's ECG feature should be used only for informational purposes, should only be used by those over 22 years of age, and is not recommended for people with known arrhythmias.

The ECG app is a software-only mobile medical application intended for use with the Apple Watch to create, record, store, transfer, and display a single channel electrocardiogram (ECG) similar to a Lead I ECG. The ECG app determines the presence of atrial fibrillation (AFib) or sinus rhythm on a classifiable waveform. The ECG app is not recommended for users with other known arrhythmias.

The ECG app is intended for over-the-counter (OTC) use. The ECG data displayed by the ECG app is intended for informational use only. The user is not intended to interpret or take clinical action based on the device output without consultation of a qualified healthcare professional. The ECG waveform is meant to supplement rhythm classification for the purposes of discriminating AFib from normal sinus rhythm and not intended to replace traditional methods of diagnosis or treatment.

The ECG app is not intended for use by people under 22 years old.

Apple has also obtained FDA approval for the feature in the Apple Watch Series 4 models that sends notifications when an irregular heart rhythm is detected through the ECG feature or through standard Apple Watch heart rate monitoring.

All ECG data gathered by Apple Watch Series 4 models is stored in the Health app in a PDF format that can easily be shared with physicians.

Related Roundup: Apple Watch 10
Buyer's Guide: Apple Watch (Caution)

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Top Rated Comments

brian3uk Avatar
89 months ago
Is anything available at launch anymore? Dual-sim nope, AirPlay 2 nope, AirPower what’s that, ECG naw, Apple Pay cash no sir, portrait mode beta. Apple has developed a bad habit it seems.
Score: 57 Votes (Like | Disagree)
OldSchoolMacGuy Avatar
89 months ago
Needs more approvals in the EU and elsewhere.
Score: 14 Votes (Like | Disagree)
baculum Avatar
89 months ago
I hope everyone knows this is pretty much worthless for 99% of users. Why don't we ALL get EKGs every day or every time we go to the doctor? because there's no reason to and it would lead to false positive diagnoses with harm caused to patients. "Should not be used for patients with known arrythmias." So this is basically for an extremely small subset of buyers who have some kind of coronary artery disease or heart pathology that makes them susceptible to possibly developing A-fib.
I understand your point, but there are myriad uses for the EKG that have great value in medical research. For example, I do research studying the EKG as a biomarker for the development of Parkinson's disease. We are working on algorithms to identify Parkinson's many years before the motor symptoms present--which would allow the intervention with disease modifying therapies at a time when they're most likely to be effective. There are numerous other examples of this, and having this type of data to mine will create amazing opportunities to identify associations with other diseases as well.
Score: 10 Votes (Like | Disagree)
rugmankc Avatar
89 months ago
What some folks are missing here is that--

1. A lot more than 1% of the US population have heart issues

2. It is a tool at the moment, not a substitute for a doctor

3. It is the future, in its early stages


Even the health features on my S0 have been useful to me.
Score: 10 Votes (Like | Disagree)
341328 Avatar
89 months ago
Crap. That sucks. Needs to come to Australia also.
Score: 10 Votes (Like | Disagree)
frankly Avatar
89 months ago
Limited to US??? Why??? This is an ESSENTIAL and sensible feature!! As someone who suffers from SVT arrhythmia this is the reason that tipped me over to buying another Apple Watch. This is utter bullsh*t. :mad:
Be patient. My guess is that there were several factors that led to this decision.

[LIST=1]
* They need to go through the regulatory agencies for each country.
* They wanted to keep this secret before announcing it and once you start going through the regulatory process, you are no longer in control of privacy.
* They need to test this close to home before opening it to a wider audience. They have to be more careful with health-related features than others.
Score: 7 Votes (Like | Disagree)