When one’s breathing is comprimised, that means that they are not getting enough oxygen into their body’s tissues. That, in turn, can make the heart try to compensate by working harder to provide more oxygen. So, sometimes this can cause pain for a number of reasons. The alveoli in the lungs of a person with emphysema are not working properly, the heart may be overworking and the nerves may be more hypersensitive to messages of pain.

However, if you are concerned, because he has had unremitting chest/neck/arm pain for 3 years, than I think that it is perfectly reasonable to see a cardiologist for an opinion regarding his heart.

I hope this helps.