I will not be of great help here but as far as I know in many cases barrel chest is initially caused by recurrent respiratory infections and especially asthma. The lungs are basically over-inflated and the chest structure changes with it. Does or did your son have asthma? I understand that not cardiac problems are causing this but that the bone deformities and their underlying pulmonary problems would have some effect on breathing and heart beat. I am not sure if you could get a referral to a pulmonary specialist to check if your son`s breathing is okay to start with. A little boy in my neighborhood is actually wearing a chest brace, some kind of corsette, to correct something that appears like a barrel chest. Sorry if this is too vague but do not panic. A few specialist should be able to shed some light on your options.
Thank you very much for your response. No, my son has never had a respiratory infection nor does he have asthma. Seeing a pulmonary specialist is an excellent idea!
dont worry too much about it as im barrel chested & fine, even Brian Denehy the actor has it & hes fine also.
I was born with a barrel chest and I'm fine.