I Just found out. That's why I took the steeps to be cautious and bought the watch: but Apple hasn't fulfilled it's part yet. So we are sitting at our place in Phoenix, for the Winter and hope that the app gets released before we go back on the road: but really not required.
I went to the hospital 5 times in the past 11 years for the same slight chest pains, as a precaution, and they all end up saying they could find nothing wrong; "You are as healthy as a 20 year old". The last time, the hospital was going to release me after 2 days and a $19,000 bill. I was to be released that day and I decided I was not told to or even suggested to do it, to walk around the whole cardiac floor, as many times as my knees and back would allow. After 4 trips around the floor, which amounted to about a mile, I went back and laid down and continued to watch TV, until I would be released. The Doctor came in and said:"You have A-Fib". I found out that I've probably had it for a long time and it manifested itself over the years in headaches, just not feeling good, slight chest pressure. It will not really affect me except it could cause a stroke, which I am on the meds for to prevent strokes. The Cardiologist explained it to me this way: Strokes are the real danger from A-Fib: Not A-Fib in itself. A-Fib is the heart valve fluttering , which allows the blood to pool and form a clot, which in turn could go to the brain and cause a stroke.
So the Apple Watch Series 4 is just another precaution on my part, so I can know when I'm not feeling exactly right, what is causing it and take necessary steps in case I am in a situation them deems it necessary.
There are a lot of people on the road, even driving semis, and people flying airplanes, that have A-Fib and don't even know it, or even hide it to keep with their employment/jobs! Without anti-clotting meds, a stroke can occur and results of the situational conditions can be overwhelming and probably have been in many cases. A lot of Stroke meds are advertised on TV every day, like Lipitor, Crestor, Zocor, warfarin, and the most common; aspirin. Some Pilots even take Aspirin, if they suspect they have A-Fib, because if they go to the Doctor, it has to be reported. Like Pilots that breath Oxygen before they fly, if they have a hangover from heavy drinking. Oxygen helps to burn or displace the alcohol content's effects on the brain. I know for a fact that Military Pilots do this before flying and it commonly known, but not reported.
That is why I believe heart monitoring and breath analyzers, should be required, for ALL Air Plane pilots and or Co-Pilots! They have device that will monitor and report the findings in real time to the proper authority/authorities.
Maybe people should be asking more questions of those that drive the roads, hauling freight, Gasoline transporters, every day, or fly our skies above us! Think about that when you see a Semi Truck, Gasoline transporter, approaching you or an Airplane overhead!
Have a nice day!