Inclusion Criteria:  For both the Thoracic Aortic Aneurysm (TAA) group and control group, there are no exclusion criteria for gender, ethnicity or socioeconomic status. However, all patients must have a minimum age of 18 years. Patients must have a diagnosis of a Thoracic Aortic Aneurysm or/and Abdominal aortic aneurysm (AAA)  The Thoracic Aortic Aneurysm groups will have:  A medical confirmed TAA defined as an aneurysm measuring >3cm in the thoracic aorta e.g. aortic arch, ascending aorta or descending thoracic aorta. Patients may also have a AAA Patients may have had a TEVAR and will have a residual sac A CT scan of the aorta in the last 3 years  The Abdominal aortic aneurysm A medically diagnosed Abdominal aortic aneurysm with a CT scan showing no TAA in the last three years. Patients who have also had their AAA repaired will also be eligible for this group.  Exclusion Criteria:  • No diagnosed TAA or AAA  No CT scan of aorta in last 3 years Under 18 years old Patient who are unable to consent