The thoracic aorta is the largest artery in your body. It carries the blood directly from your heart and is divided into the ascending thoracic aorta, the aortic arch and the descending thoracic aorta. When a portion of your aorta bulges or enlarges, it is called an aneurysm.
There are several risk factors that may cause an aneurysm, including atherosclerosis (hardening of the arteries), high blood pressure, cigarette smoking, connective tissue disorders (Marfan Syndrome), inflammatory disorders and family history.
As aneurysms are typically asymptomatic, they are often diagnosed incidentally on imaging such as a CT scan of the chest or echocardiography looking for some other disease process. If they are symptomatic, it is often the result of an aortic dissection, where blood separates the layers of the aorta presenting as a tearing, sharp type of chest pain often going into the back. This scenario is a surgical emergency with a high risk of major complication and death.
As previously stated, if a dissection of the ascending aorta is diagnosed, that is a surgical emergency requiring open heart surgery and replacement of the involved aorta with a Dacron tube graft. If it extends into the aortic root, the aortic valve may need to be replaced as well. If the descending thoracic aorta is aneurysmal, it may be repaired in an endovascular fashion by utilizing a stent graft, not requiring open heart surgery.
If it is not a dissection, treatment depends on the aneurysm location and size. If it is not large enough to warrant surgical repair, treatment is aimed at risk factor modification.