Are you on public land? If people have an opportunity to break into your stuff, they will eventually do it. No matter how good you have it chained up, it's just a deterrent. Concealment is probably more important -- if it's well hid, they won't think about breaking in in the first place. I've left tree stands and hunting carts chained out on public land for years without incident.
(I don't know about congestive heart failure, but I'm 6 years off a heart attack & open heart surgery, so good luck with all that).