Mickey,
Thanks for the post.
Unfortunately, I'm not familiar with the condition so I can't specifically advise you on what particular diagnostic course you should take.
Current cardiac CT is able to coronary vessels in adults. I'm not sure of the resolution in children. Given your history, I would make sure I was seen by a pediatric cardiologist or genetic counselor in a tertiary referral center in order to define your children's risk more thoroughly.
good luck