Addendum
You will probably be on Beta Blockers. They are required right now but they will cut your Heart rate a lot. I struggled to get above 130 and at that I was breathing hard and not able to put the effort in. I did come off them after a year but the way I managed to get the HR up at 3 months was to take the BB the night before the ride and take one immediately afterwards. And if you are going to do something stupid like come off the BB's or go for a long ride after only 3 months, do it with the advice of your doctor.
__________________
How long was I in the army? Five foot seven.
Spike Milligan