Abreviatiins can be confusing. Ascending aortic aneurysms are a type of thoracic aortic aneurysm along with aortic root, aortic arch, descending aorta and collectively called taa to minimize confusion with abdominal aortic aneurysm i.e. aaa. That said , EVAR isn't really an option with the ascending aorta. 5.0 is definitely time to meet with a good cardiovascular surgeon that specializes in these things at a high volume center. This isn't something to deal with at an average emergency room. Survival is very high at a specialty center, but not good at an average ER. I know this from experience.