Hello I am Dr. Joey. Thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 16 years of experience. I look forward to working with you.
This is a tough question. Certainly sleeping more (or even sleeping heavier) can be normal as dogs are not as bothered by noises since the hearing does diminish as the dog ages AND acting confused can be a normal age related changes. However, marked appetite changes can sometimes indicate a problem, especially if she was always a dog who loved her food. Whether or not these changes are related to the heart disease is unclear, but possible.
The best step would be a general screening (blood) if not done in the past 2 months which would include a complete blood count, chemistry profile (with electrolytes), urine check, thyroid screening AND I would highly advocate do the cardioBNP test which screens for heart disease as a blood test. If the BNP is abnormal, then she really does need a full cardiac evaluation with blood pressure check (although this is recommended to do twice yearly in dogs over 10 anyway), chest X-rays and echocardiogram.
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