Maya started coughing 2 years ago. For quite a while we had no idea what a cough from a cat even sounded like and though it was a hairball issue. Then we noticed that she would only cough when she would hiss at our late cat Orwell. We were so confused by this. We took her to her vet for her annual exam and mentioned this with no clear direction from them. We did know that she had a heart murmur. No connection though between the cough and her heart. We just kept an eye (or ear) open to it. We sill thought it could be hairballs so we were giving her hairball treatment in her food. No help. Back to the vet. Still a murmur and this time they thought she may have polyps in her throat so they wanted to put her under anesthesia to perform the procedure to check. This was risky because of her murmur, but the vet said they wanted to proceed. After dropping her off for a day without her eating for many hours, I get a call from her vet saying her heart rate will not go below 200 bpm and therefore cannot perform the procedure. This was fine by me! I knew it was not polyps. Instead they gave her an antibiotic in case she had an infection of her throat. That didn't help. We let it be for many months, not know where to go from here. Then Orwell developed intestinal lymphoma which was a sad disease to watch happen to our dear friend. After Orwell passed away 4/30/12, Maya's cough got worse. After a few visits to her vet, it was determined she has asthma. She was put on Brethine. After the cough was not improving, they put her on prednisolone. They knew the risks with her heart murmur, but they put her on a low dose. The cough got much worse in which she was heaving all night long. Took her back and they put her on more pred. She then went into heart failure. It was then determined she has heart disease.
This is just a general background of what symptoms we saw with her which determined her heart disease (HCM). Moral of the story, get your cat checked out immediately if they are coughing! If you feel you are not getting answers or being brushed off, get a 2nd opinion and take care of this matter ASAP.
Here is a video I took of Maya coughing when she got upset with Orwell. Notice how her neck is stretched out forward, how there are mucuous sounds with a lot of swallowing.