Monty:
First, congratulations on the minimally invasive procedure. I had the same procedure last year for my AVR and it really helped reduce the overall trauma. However, I guess I really don't have anything to measure it against because up until my surgery, fortunately, I had never had any other type of surgery or medical issue. I can count in one hand how the doctor visits I had during my adult life up until that point.
I was 40 at the time of the surgery and although I chose (arm twisted?!) the St. Jude mechanical valve option, complications were minimal.
Pertaining to your question, I am also an avid weight lifter, biker, runner and overall fitness nut. I love playing adult baseball and softball and tend to spend every spare moment doing something active (including chasing my two young children).
Give yourself time to recover post surgery. Go with the standard 12-week cardiac rehab that focuses on aerobics and light cable/weights. After your rehab, slowly work back into your weight lifting regime.
Personally, I cut back from my pre-operative regime of 4-5 days per week down to 2 days per week and I haven't noticed any significant drop in performance. I don't "max out" any more and I focus more on form and higher repetitions for tone. Ironically, I feel better and more rested between weight lifting workouts as a result. Plus it has freed up my time to pursue more outdoor activities such as biking.
Good luck. Remember not to overdue it the first few weeks as you will not realize how sore you truly are as a result of the pain medication. About 10 days after surgery, I moved some light boxes and my collar bones ached for thee days! Take it slow. Believe me, the last thing you will want to think about after your surgery is a bench press! Good luck!