APOE and Aortic dissection: AngII-induced aortic disease in Apoe–/– mice was first interpreted as abdominal aortic aneurysm based on external expansion of the lesion (9), noting that the term aneurysm derives from the Greek ανευρυσμα, meaning “a widening.” This observed aortic pathology was subsequently interpreted as an initial aortic dissection preceding aneurysm formation (10), although without blood within the media.