Wow! You have lost an incredible amount of weight. Congratulations!
I do think you should follow up with a cardiologist regarding your slow heart rate. It might be nothing at all to worry about but it's better to have it checked out. In my opinion, it's always a good idea to listen to your doctor : )
Wow, that's a pretty good blood pressure for that low of a heart rate! Sounds like your heart is structurally normal and efficient.
I would still get worked up by a cardiologist, not just a PCP. better safe than sorry.
I think the reason your PCP was OK with things is because your BP was good, if not a bit high even with the low heart rate. It becomes concerning when when you have the brady and your blood pressure is dropping. That would cause tiredness and other symptoms, none of which you mention, which is good.
It could be that your heart remodeled itself to pump for that extra 180 pounds you used to carry around. Now that it doesn't need to supply as much blood as it used to, it can beat slower to meet your needs. I would guess that over time it will remodel itself for your new weight. This is a similar process to when athletes train for endurance. over time the heart increases its capacity and efficiency. Because your BP is not low I doubt the brady is causing the fatigue. Over the years I've had bouts with fatigue that came and went and never could pin down the reason. Sometimes it's the seasons changing, sometimes I think it's viruses the kids are brining home from day care.