Congestive heart failure.
Can’t be that. That would require a living, pliable heart, not a charcoal black, sin seared (as opposed to sincere) heart.
I had a good friend who had CHF. He had a constant dry cough among other problems with it. One night he passed on in his sleep. Best part: He was trusting Christ as his Savior. I’ll see him again some day, and he’ll be all better.