Our dog was diagnosed with CHF and a grade V heart murmur. She is 11, almost 12 years old. She had a couple of fainting episodes within a week that the vet said would happen from time to time. After adjusting her meds she was much better. Now about a month later, she started coughing and had another episode. It wasn't nearly as long, but I can't help but panic. We also noticed that lately she holds her urine until someone comes home. She used to pee on puppy pads during the day and now she absolutely won't. It doesn't look like she's drinking water either. She drinks tons and pees tons in the evening and at night, so this sounds behavioural. But it's a concern nonetheless. We were told she has anywhere from 3 months to 2 years.