If it was my dog, and I had already spent a lot of money on his healthcare, then I would certainly treat this condition, as long as it is treatable. Early CHF is not an immediate death sentence, and he could go on to live many more reasonably comfortable years. When it gets to the point that the dog no longer has any quality of life, or is in pain, then I would let him go.

I hope poochie comes out on top in this case!