Florbetaben for Imaging of Vascular Amyloid

Inclusion Criteria: 1. suffered a recent cardiovascular event (30-120 days post ACS (i.e. STEMI or NSTEMI) or TIA/stroke with ipsilateral large vessel atherosclerotic disease confirmed on US, CT or MRI; 2. stable symptoms and hemodynamics; 3. age \>/= 18 years; 4. given informed consent. Exclusion Criteria: 1. a recent CV event likely to have been embolic in the opinion of the neurologist or cardiologist; 2. severe LV dysfunction (EF\<30%); 3. severe valve disease requiring intervention; 4. decompensated heart failure; 5. pregnancy (all women of child bearing potential will have a negative BHCG test; 6. breastfeeding; 7. women of childbearing potential who refuse to use two forms of contraception (this includes at least one form of highly effective and one effective method of contraception) throughout the study OR men capable of fathering a child who refuse to use contraception;. 8. unable to give informed consent;. 9. Florbetaben allergy; 10. glomerular filtration rate (GFR) \<50 ml/min/1.72m2 Exclusion for CTA portion of the protocol: Patients with dye allergy, or those with GFR \<60, will not undergo CTA but will have PET/CT.