is my heart involved?

I have had asthma symptoms for the last year. They were pretty well controlled with long-term inhalers and my rescue inhaler. In January, I came in contact with some toxic fumes while they were installing a fireplace insert. Since then we have been trying to reduce the inflammation in my lungs with limited success. I am on two long-term inhalers at high doses and still need my rescue inhaler 2-3 times a day.
They now they it might be a heart issue. I have Afib but that has not been an issue other than the asthma medication tripping it.
Is there any way this could be a heart issue rather than an asthma issue? My doctors are stymied? I am having additional tests but thought maybe someone could suggest something we haven't thought about.
Thanks for any help you can provide.