Hello @graeme58604, and welcome to Mayo Clinic Connect.
I'm glad you found this online support group and I hope that someone with your same surgery chimes in to answer your questions.
In the meantime, I can share my open heart surgery story with you in the hopes that there is something in common that will help alleviate some of your concerns.
First of all, thank goodness you are doing as well as you are! It is absolutely a miracle of modern medicine that we can have our chest cut open, operate on our heart, wire us back up and we go home to live another day!
I had open heart surgery at the Mayo Clinic (MN) in 2020. I was told it would take 6 months to a year for my heart to completely heal. I had a septal and papillary myectomy. They took a portion of my left heart wall and part of the top part out. My recovery was pretty normal I think. I had to wait 3 months to start cardiac rehab.
But before that, I was walking every day. I was a hard-core hiker/walker before this happened and so being in good physical shape was very helpful.
We are not as young as we once were, maybe in our minds we are, but reality is different. It takes us longer to bounce back, and sometimes we don't bounce back to where we were before.
I think you sound remarkable! I would advise you to continue pushing yourself a little bit more each day, but listen to your body too. You know you better than anyone else, so if you feel like you can walk further, walk further. If you feel like you can lift more, lift more. But also don't overdo it. Your chest was cut open. It takes time to heal completely. Eat healthy, drink water, be happy you have a brand new valves under the hood!
Were you very active before your surgery? What does your doctor say about your progress?