I brought Cotton to a new vet today for a second opinion. She read through his charts from our usual vet, and then asked me to leave him a few hours so that she could do a complete workup and x-rays.
Conclusion is that he does have an enlarged heart and severe murmur, but it is not bad enough to be causing all the hacking and coughing that he's been doing. The heart is not putting pressure anywhere near his trachea and there is no pulmonary edema, as previously assumed. The x-rays show abnormal whiteness around the oesophagus and at the top of the heart that make her think that he is sick from a bronchial infection. It's hard to tell that from x-rays of soft tissues, though, and she feels that somebody with more training should review them. So, the x-rays have been sent to a radiologist for confirmation. We should hear back next week.
He's still in early stages of heart troubles, and that will need to be treated. However, if the coughing is a bronchial issue, such as allergies, this is something we can manage.
ps - the vet expected our appointment to be a quick consult. I think she booked 15-20 minutes with me. In the end, she spent nearly 4 hours with either me or Cotton. I left home for our appointment at 6, and we didn't leave her clinic until almost 10pm. Pretty amazing, if you ask me, considering that she's never met me before today.
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