Hello Movieman and welcome to the forum! Superman referred me to your post asking if other seniors had gone through OHS. Oh yes, sometimes with repeat jaunts to the OR over a period of years. I turned 80 last November, and have had two major sternum cracking surgeries -- the first when I was 63 (replacement of aortic root and valve, a Bentall's, sounds similar to what you face), and then a second when I was 78 after a fast-growing aneurysm was detected. Actually, I had a third last June that seemed heart-related -- it was to repair a ventral incisional hernia that appeared a few months after my 2019 OHS -- a not uncommon glitch for seniors who have had multiple surgeries, but perhaps scarier than routine hernia operations because of the closeness to the aortic region. Anyway, all went well, and I have continued an active life. Love to talk long walks and even do some planking in exercise class.
If you are nervous, that only means you are human, I was my most jittery before OHS1, which forced me to come to terms with my mortality. Had to take some sleep medicine to calm my nerves in months before the surgery. In OH2, I went into the OR joking with everyone, lots of laughter, and when I came out the next day my wry-humored surgeon pronounced me the "Poster Boy for Aortic Aneurysm Surgery." Had cute UNC nurses who lined up for turns to walk with me in the hallways. By then I had an advanced sense of humor, I reckon.
Anyway, certainly plan carefully for your surgery, get everything in order, find the best surgeon and hospital you can, and rest assured that many seniors have been through all this and gratefully lived active lives. If you would like to talk further, I would be glad to do so. A long-time Richmonder, I was living in Northern Virginia when I had OHS1 at Inova Fairfax Hospital with Dr. Alan Speir, a truly great surgeon.