MIT Technology Review:

One day, while I was testing my own Apple Watch, Tom was deconstructing a rack of network equipment. He suddenly noticed his heart was pounding. Then he began feeling dizzy. Next came tunnel vision. He needed to sit down.

First he checked the pulse on his neck, but he realized his watch could provide more data. It said 203 beats per minute, so he fired up an ECG.

And:

Tom was definitely not feeling well, so he had a coworker take him to the hospital, where triage got him to a nurse straight away.

His nurse set up an ECG, the traditional “gold standard” kind, but Tom could feel that his heart rate had dropped closer to normal. He worried that the hospital test wouldn’t find anything, so he unlocked his phone and passed the readings to the nurse, who showed them to the remote teledoctor on call.

“Oh, that’s an SVT,” the doctor said, immediately. A supraventricular tachycardia: an abnormally fast heartbeat caused by irregular electrical activity.

The Apple Watch already has incredible value. Just like the camera, the best ECG is the one you have with you. So many stories about Apple Watch saving people’s lives. And this still feels like early days.