[Unklejoe]

Yeah, I’m currently going through the rounds of testing - just had the echocardiogram a week ago. Fortunately, that turned out normal. They gave me metoprolol, but that doesn’t seem to help. My potassium was kind of low, so they gave me a supplement for that, but it didn’t help either. If these PVCs keep up at the current rate, I suspect they will suggest ablation. Not really looking forward to that...

Anyway, I’m not sure exactly how Apple is analyzing the data. I’ve performed probably 15 EKGs with only one or two PVCs present, and it reported a normal sinus rhythm every time. It only reported afib once, and there were quite a few PVCs in that capture. I can email it to anyone interested.

Apparently, occasional (a few a day) PVCs are very common, so I imagine Apple had to encounter this situation during development.

[pragone]

So it's worthwhile to make sure we all understand that we're talking about two different things: atrial fibrillation and sinus rhythm are two options in the same bucket: rhythm. You can have PVCs with afib, you can have PVCs with sinus rhythm. You can't simultaneously be in afib and sinus rhythm.

I'm guessing Apple is just looking at rhythm - it would be the most reliable datapoint, as opposed to trying to measure QRS duration or analyzing for presence of P-waves, both of which differ depending on which lead you're looking at. The lead being looked at depends on which two points on the body are used to produce the tracing as well, which is not something Apple can guarantee, so perhaps that's where the explanation lies, but I have no evidence or data to back up that conclusion.