It is hard to wath them age.
It sounds like your pup is in need if a vet check.
HeRt murmurs are not uncommon in older yorkies.
Kidney problems do come up sometimes, but there are things that can be done to make it a bit better. A pup with kidney problems not being treated is going to feel terrible. ..if that is even the problem.. Bloodwork and a urinalysis is needed. What if it is as simple as a UTI... Whether or not anesthesia is safe would be the vet's call, but bad teeth can cause major problems.