Thank you for your thoughts. 18 months seemed a bit long between scans to me, but I am not an expert. Sounds like my cardiologist is also not the most qualified one to make the call. Sounds like I need to get a referral to a thoracic surgeon. Finally, how do you know about my "father in law" and his experience with this, or where you just using that term metaphorically? Kind of did a double take there. Lol.