I've had two heart attacks, The first while riding, the second about half hour after a twenty mile ride. I'm still at it. I ride in traffic, occasionally take lanes, but try to be real smart about it.
Everything in life has risks. Some activities, like cycling, increase that risk. These risks are manageable, i.e. don't skip taking meds, (I no longer do) slow down for unfamiliar curves, if there is high density, high speed traffic don't take that lane, etc.
Just some things to consider. It seems like a big decision for you two. Whatever you decide, good luck.