Never had heart surgery, but I suppose it's similar to any other type of human body mechanical repair. Only you can really answer your own question. When you feel confident that the repair was successful and you no longer feel a dependency upon your neighborhood "mechanic" in the event of power failure, then you will be free to travel again.
I had total knee replacement surgery about 2 years ago. Everyone told me to "take it easy". The doctor told me to do anything I felt like I could do. My body would tell me what I could not do. And he was right.
6 days after surgery we were camping again. OK, my wife drove the truck, but we went. It didn't matter where recovery took place, at a campground or at home.
May I suggest you consider going camping for just a week-end within an hour of your home. If, indeed, you happen to NEED that human repair mechanic, you can easily reach him/her. If the first week-end campout is successful, next week end do it again, extend it to 3 nights instead of 2.
As you gain confidence, and as you begin to feel better, you can extend the RV journeys a little longer and longer and farther and farther.
Here again, if you are up-to-it, just do it. Just don't "over do it." Restart slow, restart close to home. Let your own body be your guide. But if it were me, I'd be somewhere, not sitting at home the day the stitches came out!