Peaches, I am so sorry about your husband. Did they ever understand why this was happening? Very sorry for your loss.
Hi, I am a respiratory therapy student. I agree with what specialmom was saying here "I am sure they've suggested losing some weight. So hard but maybe worth a try. Also, lack of activity and exercise can be part of it. Which is hard and even scary to do when you have shortness of breath." and there recommendation of getting a stress test done. I Highly recommend losing weight when some one is over wight it usually causes compression of the chest making it difficult to breathe. I would also recommend seeing if he maybe can get an allergy test done he might even perhaps be asthmatic. Allergies can always form no matter what age you are.
Gosh, I'm super sorry to hear this. That's frustrating. You know something is wrong but no one gives usable help, diagnosis, suggestions! I guess on the plus side, his heart and lungs appear fine. When you say he can't breath, what's going on? Is it upon exertion or resting? That also stinks about the Mayo Clinic. Sometimes they have self pay and if you have a large deductible, it can be less than that deductible. So, might be worth checking on. But have you ever heard of the Cleveland Clinic? They are also stellar. https://my.clevelandclinic.org/health/symptoms/16942-shortness-of-breath-dyspnea I am sure they've suggested losing some weight. So hard but maybe worth a try. Also, lack of activity and exercise can be part of it. Which is hard and even scary to do when you have shortness of breath. Does he walk or anything like that? I assume he's had a stress test at a cardiologist?