Apple Watch Chief Jeff Williams Says ECG App is 'Huge Opportunity' to Empower People About Their Health

Apple today announced that its ECG app will be available on the Apple Watch Series 4 today as part of watchOS 5.1.2. Alongside that news, TIME has published a new interview with Apple's CEO Tim Cook and COO Jeff Williams.

ecg watch person
The article begins with a story about 46-year-old Texas resident Kevin Foley, who was having trouble breathing normally during a movie. Fortunately, since he was wearing an Apple Watch and participating in the recent Apple Heart Study, he was alerted to signs of an irregular heartbeat and went to the emergency room.

At the hospital, doctors hooked Foley up to an ECG machine and found signs of atrial fibrillation, an irregular heartbeat that can lead to stroke and other potentially fatal complications. Foley spent the next few days in the hospital while doctors worked to return him to a normal sinus heart rhythm and is doing fine now.

"Apple's largest contribution to mankind will be in improving people's health and well-being," Cook boldly proclaimed.

"We have tens of millions of watches on people's wrists, and we have hundreds of millions of phones in people's pockets," said Williams. "There's a huge opportunity to empower people with more information about their health. So this is something we view as not only an opportunity, but a responsibility of ours."

Williams also appeared on CBS This Morning today to talk about the ECG app. The YouTube video can only be streamed in the United States.


The report says a traditional hospital ECG is often referred to as a "12-lead" machine, as its 10 different electrodes provide information on 12 different areas of the heart. The new Apple Watch is the equivalent of only a single-lead device, but research suggests the ECG app is still very accurate.

In a press release, Apple said the accuracy of its ECG app was validated in a clinical trial with around 600 participants. The study found the ECG app on Apple Watch demonstrated 98.3 percent sensitivity in classifying atrial fibrillation:

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.

"The FDA has been very rigorous, and they should be," said Williams, referring to the Apple Watch's heart health features.

The article goes on to claim that some cardiologists and other experts have raised concerns that the Apple Watch's ECG feature is "unnecessary for the general population" and "could cause problems," including false positives.

"If everybody with an Apple Watch and an alert from an Apple Watch went to a heart-rhythm doctor that was super comfortable with this, then I think it would be O.K.," said Dr. John Mandrola, a cardiac electrophysiologist. "But there are going to be millions of people going to the doctor that in many cases will be just fine."

Apple responded that no medical test is 100 percent accurate, so some false positives are inevitable, according to the report. Moreover, the Apple Watch will only alert users to a potential heart-related problem if it detects five instances of what it considers a cardiovascular episode, including arrhythmia.

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.

Irregular heart rhythm notifications will also be available on Apple Watch Series 1 through Series 4 models in watchOS 5.1.2.

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.

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. At launch, the ECG app will be limited to the U.S., but Apple is likely working to get regulatory clearance elsewhere.

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

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Top Rated Comments

groadyho Avatar
86 months ago
Tbh, this is just the beginning. Pretty cool stuff. Hypochondriacs unite
Score: 11 Votes (Like | Disagree)
yaxomoxay Avatar
86 months ago
Sadly, this is a gimmick feature.
As someone that had open heart surgery, I strongly resent this statement. Is the AW going to be THE main check-up tool? No. But it provides a level of flexibility and continuous availability that was not possible before - at least not without some "unnatural" intrusion such as a band. This is just a watch with an important functionality added.
And heck, I'd rather bother my doctor with a few false positives than risk missing an important true positive. You know, I pay him and he accepts the payment, which will include this type of services.
Score: 9 Votes (Like | Disagree)
AngerDanger Avatar
86 months ago
Well, he was hardly going to say, "The ECG barely works, and even if it did, I'm still not sure why anybody would actually use it. What are they even for? Getting hearts or something? The thing is, most people already have hearts."



Attachment Image
Score: 8 Votes (Like | Disagree)
Mtmspa Avatar
86 months ago
Sadly, this is a gimmick feature. The only thing it will do is freak people out and send them to cardiologists. I think cardiologists will get the most gain from this feature, as the number of people trying to see a cardiologist will increase exponentially. The EKG with two leads is useless. It tells you nothing. It's not bad for you; it just gives you no reliable information (good or bad). People who would take their EKG with an Apple Watch and pay attention to the results are already concerned about heir heart heath. Those who are not concerned, will not even waste time on this feature. Those who are concerned need to see a cardiologist and not rely on this gimmick.

Even when you see a cardiologist, the real 12-lead EKG tells you very little. I am in the process of being seen by a cardiologist the first time in my life. I had the real 12-lead EKG done, and it came back absolutely normal. Because of the symptoms that I have, the doctor ordered an Echo Cardiogram, which came back normal as well. Then, he ordered a stress test, and saw something that could point to a Coronary Arterial Disease, it is inconclusive, so more testing is needed. The next step is a non-invasive CTA (CT Angiogram), which has a 91-95% accuracy rate. After that, the most conclusive test is the the intrusive angiogram with a scope inserted through the arteries into the heart. That's how much testing is required to conclusively diagnose a heart condition.

An Apple Watch with two leads for EKG is a toy. I hope Apple will sell more Apple Watch Series 4 because of this gimmick, but personally, I chose to keep my Apple Watch Series 3. Frankly, I would prefer Apple improving the heart-rate monitor reliability in the Apple Watch, as the existing one has very low accuracy.
What are your qualifications for this rant?
Score: 7 Votes (Like | Disagree)
citysnaps Avatar
86 months ago
I bought a SEIKO watch in 1994 that had a built-in blood pressure monitor. It was a disaster.

No, but I have half a brain.
[doublepost=1544111585][/doublepost]
Never mind. I like it. I want Apple to sell more Apple watches. Really. I do. I'm a shareholder, and anything helps right now.
Thanks for the heads-up. Your views can then be safely ignored on this matter.
Score: 6 Votes (Like | Disagree)
citysnaps Avatar
86 months ago
Sadly, this is a gimmick feature. The only thing it will do is freak people out and send them to cardiologists. I think cardiologists will get the most gain from this feature, as the number of people trying to see a cardiologist will increase exponentially. The EKG with two leads is useless. It tells you nothing. It's not bad for you; it just gives you no reliable information (good or bad). People who would take their EKG with an Apple Watch and pay attention to the results are already concerned about heir heart heath. Those who are not concerned, will not even waste time on this feature. Those who are concerned need to see a cardiologist and not rely on this gimmick.

Even when you see a cardiologist, the real 12-lead EKG tells you very little. I am in the process of being seen by a cardiologist the first time in my life. I had the real 12-lead EKG done, and it came back absolutely normal. Because of the symptoms that I have, the doctor ordered an Echo Cardiogram, which came back normal as well. Then, he ordered a stress test, and saw something that could point to a Coronary Arterial Disease, it is inconclusive, so more testing is needed. The next step is a non-invasive CTA (CT Angiogram), which has a 91-95% accuracy rate. After that, the most conclusive test is the the intrusive angiogram with a scope inserted through the arteries into the heart. That's how much testing is required to conclusively diagnose a heart condition.

An Apple Watch with two leads for EKG is a toy. I hope Apple will sell more Apple Watch Series 4 because of this gimmick, but personally, I chose to keep my Apple Watch Series 3. Frankly, I would prefer Apple improving the heart-rate monitor reliability in the Apple Watch, as the existing one has very low accuracy.
Just curious...are you a medical doctor or medical research scientist?
Score: 5 Votes (Like | Disagree)