The electrocardiogram (ECG) app measures heart rhythms and lets users know if their heart is beating too fast, too slow or irregularly. The innovative feature could save the lives of millions.
Apple has been developing the ECG app for several years now and worked closely with the Food and Drug Association (FDA) to get the feature approved in America.
However, for the update to be made available in the UK - Apple would need approval from the Medicines & Healthcare Products Regulatory Agency (MHRA) and would likely have to start their clinical trials over again in order to do so, so UK Apple Watch 4 wearers may have a wait on their hands before the feature is made available to them.
The new ECG feature makes use of the existing hardware in the Apple Watch 4 and is made available through an update to the watchOS.
For the first time ever, it will allow consumers to take independent electrocardiograms straight from their wrist. The ECG feature on Apple Watch Series 4 is the first direct-to-consumer product that monitors the heart.
The app detects when changes occur in a person's heart rate. The Apple Watch 4 alerts the wearer to irregular heartbeats at the precise moment a rapid beat or skipped palpitation is experienced.
Unlike previous health monitoring fitness trackers, Apple's ECG app detects irregular heartbeats that could be connected with atrial fibrillation (AFib), which is thought to be the cause of one in three strokes. Critical information can then be fed back to the wearer's doctor via a PDF.
It is hoped that the Smartwatch app will identify people suffering from AFib in the early stages and help to prevent strokes and heart attacks.
The ECG app works together with electrodes built into the watch's back crystal and digital crown. To get a reading, users simply activate the app and hold their finger on the digital crown.
Electrical signals measure the wearer's heart rate and provide a reading after 30 seconds. The results will show either AFib, sinus rhythm or inconclusive and record the data in the Health app on iPhone.
The Health app will inform users what the symptoms mean in layman's terms. Users that are concerned can share their results with their doctor.
It's more than likely Apple are already seeking approval in countries outside of America for their ECG app update, but they've yet to release any information on when it could be made available.
In the UK for example, it's possible the MHRA would require Apple to carry out clinical trials on the safety and accuracy of its data, and a clinical investigation in order to obtain CE marking could take years.
To have the feature approved in American, Apple has already provided study data to prove the ECG app works. The tests involved 50% of participants that suffered from AFib and 50% of participants that had a normal heart rate.
Apple was able to show the ECG app has a high level of reliability. Tests results showed that 98% of the readings were accurate. In comparison, doctors were only able to identify 90%.
For approval in other countries however, it's likely Apple will have to carry out trials on new participants again.
While Apple confirmed the ECG update was made available in the watchOS 5.1.2 update issued on 6th December, it's not possible for users outside of America to access the update.
However, some Mac sites have already commented that users can't workaround the limitation by switching their region to the United States in order to gain access to the new feature.
For now, despite the Apple Watch 4 costing from £399, significantly more than most other fitness tracking apps, users in the UK will have to wait for regulatory approval before they can access this new feature.
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