It is a concern if it is new.
Or, if he has symptoms.
If he is on a beta blocker or calcium channel blocker , this might be the reason.
I suggest he have an EKG today if this is more than one reading.
Since he just had surgery, is is somewhat more likely to have a heart block condition develop.
This needs to be looked into, we can not examine him, take him to the ER or urgent care.
And if he is normally not this low, then this is even more concerning.
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