Your pet's health is a source of significant worry. Immediate attention is recommended to prevent further complications. Act now to ensure the well-being of your pet. Get expert guidance and timely intervention for their health concerns.

It sounds like your Shih Tzu is having some digestive troubles, especially with the vomiting and lack of appetite you've noticed. The yellow color in her vomit is often a sign of bile, which can happen when her stomach is empty. This might be because she's not eating regularly, leading to a build-up of bile and subsequent vomiting.

Given her history of heart failure or a murmur, it's important to approach this with care. Here are a few steps you can take at home to help her:

Firstly, consider making some dietary adjustments. Offering her small, frequent meals instead of one or two large ones might help. Bland foods, such as boiled chicken and rice, can be gentle on her stomach and might encourage her to eat.

It's also crucial to ensure she stays hydrated, especially if she's been vomiting. Make sure she has access to fresh water regularly, and if she's hesitant to drink, you might try offering her ice cubes.

Keep a close eye on her for any additional symptoms, such as lethargy, changes in behavior, or further vomiting. It's also important to provide her with a quiet, comfortable place to rest and recover.

Since the vomiting isn't ongoing and there are no other symptoms at the moment, monitoring her condition is key. However, if her appetite doesn't improve or if the vomiting starts again, it would be wise to consult with a veterinarian to rule out any underlying issues, particularly given her heart condition.

If you have any further questions or need more guidance, please feel free to reach out. Thank you.