A future Apple Watch could take heart-rate monitoring to the next level with a built-in electrocardiogram.

Speaking to people familiar with the plans, Bloomberg reported that the incorporation of an EKG is a broader plan from Apple to take its luxury smartwatch and turn it into a serious medical device.

The Apple Watch currently sports a basic heart-rate monitor, which is focused on fitness and collects historical data. A built-in EKG in the Apple Watch, however, would be able to detect any abnormalities such as irregular heart rates, which can increase the risk of strokes and heart failure.

Last month, the tech giant launched the new Apple Health Study app, which will use the Apple Watch’s existing heart-rate monitor. A joint project with Stanford University, the app will passively monitor a user’s heart rhythms and heart rates for signs of atrial fibrillation, or AFib. Millions of people suffer from AFib, according to Apple, but are unaware until it causes a serious condition. The Apple Health Study app will alert users if it detects any irregularities and will also share the information with medical researchers working to further understand the condition.

The Apple Watch is already saving lives after a story emerged last week of Scott Killian, who was alerted to his elevated heart rate by a third-party Apple Watch app while sleeping. A trip to the emergency room, an EKG and several tests later, it turned out Killian had four blocked arteries. If he had continued sleeping, according to the surgeon, Killian would have died in his sleep.  

One way that Apple could incorporate an EKG monitor into the Apple Watch, according to Bloomberg, is by having a user squeeze the frame of the Watch with two fingers. An imperceptible electrical current would travel across the person’s chest to the heart. The EKG would be able to monitor the health of the user’s heart and possibly spot any problems early. The development process, however, is still ongoing, according to the sources, and the EKG feature could work differently or the company could choose not to incorporate it at all in a future Apple Watch.

Last month, AliveCor Inc. received approval from The Food and Drug Administration for its EKG Kardia Band, the first medical-grade accessory for the Apple Watch. While the strap has been on sale in Europe for a few months, but FDA approval now makes it available in the U.S.

Led by increased shipments of the Apple Watch, smartwatch shipments will more than double by 2021, according to International Data Corp. In 2021, the number of smartwatch units shipped will jump to 71.5 million, up from 31.6 million this year.

Image: Apple