Reddit:

Ok holy hell…. strap in.

If you have the Apple Watch 4 please please update to the new firmware released yesterday and take your ECG.

I did last night and tried it out. Weird. Abnormal heat rate notifications. Ran the ECG app and came back afib. Well…glitchy firmware. Let’s try again. Afib. Again and again and again. Piece of crap watch.

My wife wakes up and I put it on her. Normal. Normal. Me afib. Try the other wrist, try the underside of the wrist. Every time afib warning.

As always, take what you read on Reddit with a grain of salt but, if true, this is an incredible story and one I’m sure will be repeated.