Fast breathing with mouth open after running

Hey, my cat is about 8 months old. I've been noticing for a few days that he opens his mouth for a bit. Today after running, he lay down and started breathing fast with his mouth open - his tongue was inside. And a few days back he wanted to throw out something but but seemed like he was choking. He's eating ok, he's active and playful but these things concern me. He's a Persian. Is it because he's feeling hot?

ANSWER:

The signs you describe can be from feline cardiomyopathy which is a thickening of the heart muscle, is sometimes a genetic disorder of Persians, and is serious. For this reason, you should take your cat to the vet right away. I certainly hope this is not the case, but better safe than sorry because the disease can be controlled for years in many cases with feline medication.

Best,
Dr. Neely