I didn't begin to feel any "different" or have symptoms until I was around 35. And even then, it was only shortness of breath with exertion.
The surgery was not as bad as I imagined it would be. It took a lot of thought to decide on a valve. Tissue or mechanical. The mechanical valve lasts longer, possibly forever, but you have to take Coumadin (blood thinners) for the rest of your life, also they are quite noisy. Tissue valves wear out in about 10-15 years and need to be replaced, but no blood thinners (less chance of developing clots) and they aren't noisy. I also have Crohn's disease, so blood thinners aren't a good option for me.
I went tissue valve and my surgeon likes the bovine (cow). I was in the ICU after surgery for around 16-20 hours, extubation in 6 hours. Just 20 hours after surgery, I was on my feet and walked to my wheelchair to be taken to the cardiac step down unit. I was home just 4 days after surgery. I went back to work 5 weeks post op and was running at 7 weeks post op.
My chest is still sore, it's bone and nerve pain, but I'm better every day (I think the healing is harder on women because of our breasts). I feel better and have more energy than I did b4 surgery. I'm less scared to exercise now. It is a bit daunting to know that I will have to do it again in 10-15 years, but it is what it is and I'm happy to have had the surgery. Of course in my case I had a life threatening infection and the surgery saved my life! Science is cool.