Dear Bigmak,
As you said, these defects are rare and pediatric cardiac surgeons do try to not intervene on these, especially if they're small. The surgery performed is a Dor procedure, in which the aneurysm is opened and patch is sewn inside to protect the site of the aneurysm. Then, the aneurysm is closed back up. It's a procedure that has been performed much more in adults than in kids, though, in hearts that have different problems, so you cannot extrapolate adult data and adult heart problems to that of kids.
Unfortunately, there is essentially no research that reviews this data in children, from what I can find. I would recommend that you discuss this further with the surgeon and ensure that this procedure truly needs to be performed. As well, I would make sure that you get several opinions from different institutions regarding this intervention.
Thank you very much for your help!! I will definatly consider getting a second opinion, especially at CHOP. I have heard they also have an excellent reputation!!