The aorta, the largest artery in the body, transports oxygen rich blood from the left ventricle of the heart to the rest of the body. As it emerges from the left ventricle of the heart, the aorta has the shape of a walking cane, with an ascending part, an arch, and a descending part that travels through the chest and continues into the abdomen. From the aorta, branches to the head, arms, chest, abdomen, and legs supply the body with oxygen and nutrients.
What is an aortic aneurysm?
An aortic aneurysm is a dilation, bulging, or ballooning of a weakened part of the aortic artery wall. The normal pressure of blood from the pumping of the heart causes the weakened portion of the aorta to slowly stretch and bulge, leading to the formation of an aneurysm. Aortic aneurysms are named according to their location:
- thoracic aortic aneurysms are those that form in the chest cavity
- thoracoabdominal aneurysms extend from the chest into the abdomen
- abdominal aortic aneurysms occur exclusively in the abdominal portion of the aorta
Regardless of their location, aortic aneurysms are dangerous because of the risk that they will rupture, causing life-threatening hemorrhage.
What are the risk factors for aortic aneurysm?
Disorders such as emphysema, chronic hypertension or atherosclerosis, inherited diseases, such as Marfan's syndrome or Ehlers-Danlos syndrome, and smoking can increase the risk of aortic aneurysm formation. The children of people with aortic aneurysms are also at increased risk for aneurysm formation.
What are the symptoms of aortic aneurysm?
Often, individuals with aortic aneurysms do not have specific symptoms; rather, the main complaint can be vague pain in the chest or abdomen. Thoracic aneurysms can affect nearby structures, like the trachea, causing a persistent cough. Compression of nerves by a thoracic aneurysm can cause hoarseness. In severe cases, abdominal aneurysms can cause gastrointestinal bleeding. In some cases, people might feel a pulsing in the abdominal or thoracic area where the aneurysm is located. The symptoms of a ruptured aneurysm include a sudden intense back or abdominal pain (or chest pain, in the case of a thoracic aortic aneurysm), or signs of shock such as shaking, dizziness, fainting, sweating, rapid heartbeat, and sudden weakness.
How is an aortic aneurysm diagnosed?
Since aortic aneurysm often does not produce symptoms, it is important for people at increased risk for aortic aneurysm formation (for example, those with a family history) to undergo screening for the condition with noninvasive testing. Aneurysms can also be discovered during a routine medical examination, during an abdominal surgery, or during a diagnostic imaging test. The common diagnostic tests for aortic aneurysm are
- computerized tomography (CT) scan
- magnetic resonance imagery (MRI)
What are the treatment options for an aortic aneurysm?
Treatment for an aneurysm varies according to its severity and size. If a rupture is not imminent, the physician may decide to monitor the growth of the aneurysm using ultrasound and CT scans, and attempt to lower the pressure on the aneurysm using medication to lower the blood pressure. Thoracic or thoracoabdominal aneurysms whose diameter is twice the size of the normal aorta – or about 5.5 cm – should be considered for surgical repair. In some cases, a minimally invasive procedure called endovascular stent graft aortic aneurysm repair may be performed.