Will my thoracic aneurysm burst? it is a 4

Depends on the type : Usually 4 cm aneurysms in teh aorta do not rupture. Usually! however a particular type called saccular aneurysms may. Also the location of aneuyrysm is important. 4 cm aneurysm in the iliac artery is very serious. As compared with aortic aneurysm of the same size.

Low risk: But needs careful followup.?Ascending, or descending? Need echo to be aware of aortic valve status and any post stenotic dilation instead of aneurysm no smoking blood pressure control and baseline work up and followup echo and or ct scans.