An aneurysm is an abnormal enlargement in a blood vessel, and it can occur anywhere in the body. When an aneurysm occurs in the aorta—the blood vessel that carries blood away from the heart to all parts of your body—it is either a thoracic aneurysm, located near the heart, or an abdominal aneurysm, located in a descending portion of the aorta.
When the aortic wall enlarges, it becomes thin and tense, and like an expanded balloon, it can rupture or tear. This can be a life-threatening emergency. When detected in time, the aneurysm can be repaired with open-chest surgery or a newer, less invasive technique.
Causes and symptoms
Aneurysms are most often caused by atherosclerosis—hardening of the arteries. Other causes are chronic high blood pressure, smoking, high cholesterol and certain diseases that weaken the aortic wall. In some instances, an aneurysm results from a congenital abnormality.
Generally there are no symptoms, but the aneurysm is detected during an examination for a different medical condition. Large aneurysms can be seen on a chest X-ray. They are also detected by a CT scan, MRI or echocardiography.
How is the aneurysm fixed?
Surgical repair is complex and requires an experienced cardiothoracic surgical team to cut through your breastbone and expose the aorta. A heart-lung machine is used to maintain circulation while our surgeon removes the diseased portion of the aorta. Clamps are placed above and below the aneurysm, which is then cut out and removed, and a graft, or fabric tube, is sewn onto both cut ends. The breastbone is permanently wired closed.
A less invasive technique used by our surgeons involves placing a stent graft inside the diseased segment of the aorta to “reline” the aorta like a sleeve. The stent—a tiny, wire mesh tube—is inserted from outside your chest through a catheter that is put through an artery leading to the aorta. The stent graft works as a scaffold or buttress and can relieve most of the pressure of blood flowing through the aneurysm, preventing rupture.
Depending on your particular circumstances—age, size of the aneurysm and its position, your surgeon will make the best judgment about which treatment is appropriate for you.
Some aortic aneurysms are located very close to the aortic valve (the valve that allows blood to leave the heart); this may cause the aortic valve to function improperly and let blood leak backwards with every heartbeat. When this happens, the preferred surgical procedure may be to replace both the diseased portion of the aorta and the valve to which it is attached.