An aortic aneurysm is dilation (enlargement) of the aorta, the large blood vessel arising from the heart and coursing down through the chest. This enlargement weakens the wall of the aorta and can result in tearing (dissection) or rupture of that portion of the aorta.
Aortic aneurysms are classified by location in the body. Thoracic (chest) aneurysms can be ascending (just above the heart), arch (involving the blood vessels serving the head and arms) or descending (in the back of the chest, near the spine). Abdominal aneurysms are located in the belly, below the diaphragm. Aneurysms that extend from the chest into the abdomen are termed thoracoabdominal aneurysms.
Treatment of aortic aneurysm requires control of blood pressure and regular imaging to monitor for continued enlargement. When an aneurysm approaches 5 cm in diameter, elective surgery is generally recommended. Patients with connective tissue disorders or a family history of aneurysm rupture or dissection should consider early surgery.
Aortic dissection occurs when the inner lining of the aorta splits and the blood flow separates the layers of the aortic wall. This is a life-threatening problem and often requires emergency surgery to replace the torn portion of the aorta. Aortic dissection can occur in the presence of an aneurysm or in the setting of connective tissue disorders such as Marfan syndrome.
Surgical treatment of aortic aneurysm and dissection depends on the location and severity of the problem. Some patients can be treated with less invasive procedures (endovascular surgery) such as placement of an aortic stent-graft. More extensive aortic disease requires surgery to replace the diseased portion of the aorta, or a combination of open surgery and endovascular procedures.