In my experience (in my non-US country) doctors don't make much use of heart rate for diagnosis at all. We check things with a pulse oximeter when feeling unwe

In my experience (in my non-US country) doctors don't make much use of heart rate for diagnosis at all. We check things with a pulse oximeter when feeling unwell and quite often we see elevated heart basal rates associated with infections, uncorrelated with body temperature. These tends to correlate quite fell with feelings of tiredness/uncomfort. I found it interesting that doctors most of the times feel entirely uninterested with this.