Are there warning signs for an aortic aneurysm? any ways to prevent one? is there an exam that shows if you are susceptible to one?

Sometimes: Sometimes there are no symptoms and it is picked up by ultrasound or a good physician exam. Get checked out by your doctor to see if you need an ultrasound.

Perhaps: Positive family history, marfans or connective tissue disease, hypertension, smoking, no absolute predictors, but good accurate exams and imaging are available. Aneurysm can affect any part of the aorta - chest, abdomen pelvis and any named vessel! so full history and exams are relevant.