Hmmm, pretty offensive title, but whatever floats your boat.
Wow, 2 heart surgeries at such a young age. Any "professional" around here is not going to offer you advice. Just too risky. You are certainly categorized as extremely high risk. I would speak to your doc.
Feel free to read around though, and see what you can pick up. Just understand, most recommendations you see, especially those coming out of my mouth, are assuming good health.