Thoriac aneurysm symptoms ? can teens have them, teens who exercise regurarly

Often none: Thoracic aortic aneurysm often have no associated symptoms. Sometimes there will be chest and/or back pain. Most are found incidentally. Aneurysms increase in frequency as patients age. They're very uncommon in teens. For it to occur in a teenager i would bet there was an associated problem with tissue strength (collagen-vascular disease) like marfan's syndrome. Exercise doesn't increase risk.

Yes: Rare in teens many are not symptomatic early. When symptoms occur it is usually chest pain of substantial degree with expansion or leakage.