An aortic aneurysm is an abnormal enlargement or bulging of the wall of the aorta. An aneurysm can occur anywhere in the vascular tree. Once and aneurysm is diagnosed, treatment may be needed, depending on the size of the aneurysm. Ruptured aneurysms require emergency surgery to stop the bleeding.
The aorta has many layers. Aortic dissection is a tear that develops in the inner layer of the aorta, causing blood to flow between the layers. The layers then separate, interrupting the blood flow and possibly causing the arterial wall to burst. Aortic dissection can be a life-threatening emergency, in some situations requiring emergency surgery to repair or replace the damaged segment of the aorta.