The Apple Watch Series 4 was unveiled on September 12, 2018 at the Steve Jobs Theater in Apple Park, where the company showed us a complete redesign of the device that included a 30% larger screen and a new processor called the S4 that made us wear a 64-bit processor on our wrist for the first time.
It was a presentation in which the brand’s intelligent watch took on a strong role in the field of health . In the last generations, the Apple Watch has been positioned with an important trend towards sport, with alliances as important as the one we saw since the Series 3 with Nike. However, this new Series 4 came to show that this watch can be much more useful than a mere companion in our training.
The changes in hardware and the complete remodelling of the new integrated cardiac electrodes brought something unprecedented to consumer devices: for the first time, this new device is capable of performing an electrocardiogram on the user, in 30 seconds: without the need for extra accessories, and after certification by the medical authorities of each region ( in our case, at European level ). We only needed that after the pertinent approvals and the update to watchOS 5.2 , Apple would activate this ECG functionality that is available from this very moment.
With the ECG app we will be able to do an electrocardiogram from Series 4, but from Series 1 onwards it will also measure our arrhythmias
There is another feature that will be available from today, and this time from any Apple Watch Series 1: it is the irregular heart rate detection . What the Watch does is analyse the heart rate in the background on an intermittent basis, and it will alert the user if an irregularity in the pattern is detected, as this may be a symptom of atrial fibrillation – or if it is above or below a certain threshold. This does not require an Apple Watch Series 4, which is essential for EKG functionality.
What is an EKG?
It should be made clear that ECG activation is completely optional and is deactivated at the factory. Once Apple enables the possibility, it is the user who confirms that he wants to use it through a simple process that I will explain later. First of all, let’s understand what we are measuring with this new feature.
The electrocardiogram is a painless process that records the electrical activity of the heart
An electrocardiogram is a process that measures the electrical activity of the heart , that is: when the heart beats, an electrical signal circulates through it. The ECG shows whether the heart is beating at a rhythm and was normal because of the measurement of this signal. The traditional way of making these measurements was to go to a doctor’s office, where electrodes are distributed throughout the body. For approximately three minutes ( with these electrodes ), a computer records the electrical activity of the heart.
The recording of this electrical activity of the heart may show an abnormal ECG which may be a sign of heart damage or disease, which should be treated by a doctor as soon as possible. It is advisable to have a medical check-up with ECG in people who have symptoms such as chest pain, frequent tachycardia, arrhythmias, difficulty in breathing, etc… or routinely as a possible control. It is completely painless , and it is important to understand that the process does not circulate electricity from the electrodes, only records it.
Enabling the ECG app on the Apple Watch Series 4
First of all, we have to have the watchOS version 5.2 installed on the clock. From this moment, we open the Watch app on the iPhone and go to the section HeartSet up the ECG app in Health . Immediately we will enter the Health app of our phone, where some introduction screens will explain what the ECG is and what it is for – and what it is not for. There is nothing more to set up than simply entering our date of birth.
After an introduction screen, we simply have to go to the app ECG in the Apple Watch itself . There are no more configuration processes or customizations here, just follow the on-screen instructions: stand in a comfortable place, let your arms rest on a table or your lap and simply keep your finger on the digital crown of the watch.
With this gesture we close the electrical circuit and these variations in it can be measured through the new sensors of the Apple Watch Series 4 . While we are performing the check, we should not move much or talk. Of course we will not notice any pain, not even tickling in the middle of the test: it is totally painless and fast, in only 30 seconds we will have the diagnosis. If for whatever reason we interrupt it, we can start it again by keeping the finger on the digital crown again.
What the Apple Watch Series 4 ECG app records
In the introduction screens, Apple makes it clear that an ECG in the Apple Watch is used to record the physical activity of the heart in search of arrhythmias that could lead to atrial fibrillation , and shows us the result within the classification of the most common ones:
- Sinus rhythm: this is the normal result, where the heart beats in a uniform pattern.
- Atrial fibrillation – the heartbeat is irregular. This is the most common type of serious arrhythmia and we should see a doctor for a complete check-up.
- Low or high heart rate: Occurs when the heart rate is less than 50 beats per minute or more than 120 BPM In these ranges, the app is not able to check for atrial fibrillation.
- Inconclusive: happens when you cannot sort according to the current records and patterns of the app. It can happen for different reasons, for example, because the measurement has been incorrect: bad positioning of the Apple Watch, movement during the test, etc…
Apple also explains that this app can’t detect heart attacks ( even warns us while it’s taking our frequency log ), as well as strokes and blood clots. Nor does it detect other heart disorders than those listed above, such as high blood pressure, heart failure, high cholesterol levels or other types of arrhythmia. In any case, always common sense in all this, and beyond the results it is always convenient to go to a doctor for a more in-depth diagnosis – although this app can help us to discover heart irregularities that we may not have known we had, and prevent further damage.
What are irregularly paced notices
In addition to the ECG app that is only available on the Apple Watch Series 4, the irregular rhythm detection has also been activated today, which is basically a notification if it detects during several measurements irregular rhythm that could be due to atrial fibrillation. Early diagnosis of this problem is important to prevent major problems, e.g. a stroke.
Early detection of heart irregularities can help prevent further health problems
In any case, if we are detected this arrhythmia can be temporary or persistent, but the important thing is that it can be controlled with medical attention and medication. Again, the only configuration for this detection is to enter our date of birth and that’s it: the watch will perform checks with the heart sensors with various readings each day and will evaluate if an irregularity is repeated too much and the time between them, to warn us.
Here as I say we simply have to activate the option in the iPhone app Watch, and without further ado, wear the watch . In case we have any such detection, the clock will alert us with a message and a small explanation of what it seems to have detected.
How to use the results
Knowing what we are measuring, and how to measure it, it is time we used the results. When one of these measurements is finished, the Health app will send a notification to the iPhone , where we can see all the details of the test. We’ll even be able to generate a PDF that can be shared through the usual means ( mail, messages… even AirDrop ) to show the doctor if the app detects any arrhythmia.
Apple’s work has been supported by a medical study conducted by Stanford University
Apple has worked with medical authorities in the US to obtain a useful PDF format and how for professional review, and commissioned a study from Stanford University on the sensor reliability of the Apple Watch Series 4: the results were compelling, with 98.3% sensitivity for detecting atrial fibrillation, and 99.6% when classifying sinus rhythm. We can fully rely on the device for these processes ( and in each region where it is activated it is preceded by competent medical approval ).
It is without doubt an incredible feature (bordering on science fiction ) of what we cannot forget is a watch: it is fascinating how comfortably we can do an ECG without connecting electrodes or any extra accessories, with this degree of reliability. Not to mention that it can, of course, warn us of problems before we are even aware of them – with the possibility of treating them in time and improving our quality of life .