Our 13 yr old sht-tzu has not been eating very much lately. Have tried all kinds of food for him. Is there anything we can do to stimulate his eating? He has been diagnosed with some heart disease by our vet. Thank you ken hobbs

Most cases of not eating are from being sick or overfeeding. Please see the sticky at https://www.askmehelpdesk.com/dogs/information-articles-our-dogs-expert-labman-53153.html#post254171

If you are really concerned and your dog is losing a lot of weight I would check with your vet; however, I know it is not uncommon for older dogs to sometimes loose their appetites for whatever reason. You might try a supplement they carry at Petsmart or other pet supply stores. It is meant to stimulate appetites in older dogs.

There is no indication in the OP that the dog is underweight. As I said, most dogs that won't eat are sick or over fed. An appetite stimulate won't cure a physical problem, and is the last thing an inactive dog needs.