I have an elevated diaphram also. They don't know why I have it but I have had it for a number of years. I went through a number of tests early on but they were never able to find the cause. I mainly get winded easily with exertion. I am also overweight and have some asthma which dosen't help. My lung capacity tests have decreased over the past couple of years and I am due to see my pulmonologist in about a month. Recent CT scan of lung was negative. I wonder if plication would be helpful to me (I am 55)
I am sorry you have had this complication. I don't think it is uncommon. If the problem is just on one side, then a plication may help. Your pulmonologist should know this, and if they don't, find another pulmo.