Fletcher sounds like Max, he has had bouts of excessive panting for about three years, but only in the summer when it gets hot until this last year. My vet has checked all the usual stuff, thinks if it is LP it is in the very early stages. She suggested my next step was a specialist, since it really isn't clear what is going on. So, I guess that's next for him. If I had a definite diagnosis and an otherwise healthy 13 yr old, I think I would do the surgery, I have heard nothing but good results from others, even with older dogs.