I'm an avid golfer and golf was one of the last things my surgeon allowed me to do. I had to wait 12 weeks postop (full sternotomy, AVR and root aneurysm). My first postop round was a joyous occasion for me, even though my score wasn't great. I appreciate golf even more now than I did before I wasn't able to play for 3 months in peak season (May, June, July).
It was a bit uncomfortable at first, but mainly just stiffness. I don't really notice it now, 3 1/2 years later.
Best of luck to you. Hit them long and straight, and drop those 10 footers!