What is an Aortic Aneurysm?

The aorta is the largest artery in the body. It carries oxygen-rich blood from the heart throughout the body. It passes through the chest and abdomen giving off branches to the head, arms, abdominal organs and legs.

An aortic aneurysm is a dilation or ballooning of the aorta. The most common location for an aortic aneurysm is the abdominal aorta below the level of the kidneys. An aneurysm in this location is referred to as an AAA, “Triple A” or Abdominal Aortic Aneurysm. The normal diameter of the aorta in this location is 2.5 centimeters. We call the aorta aneurysmal when it is 3 centimeters or greater in diameter.

Aneurysms occur in 5-10% of men over the age of 60 and in 30% of men over the age of 80. Risk factors include family history, high blood pressure, hypercholesterolemia, and smoking. Aneurysms generally grow about 10% of their diameter (or approximately .5 centimeters) a year. Uncontrolled high blood pressure and smoking are correlated with faster rate of growth and increased risk of rupture. Like a balloon filled with air, the larger an aneurysm gets, the more likely it is to rupture:

Most people (60-90%) with ruptured aneurysms die.  Most people with aneurysms have no symptoms and their aneurysms are discovered incidentally when of being tested for another problem. First degree relatives of patients with aneurysms should undergo a routine AAA screening ultrasound at age 50.

The symptoms of a ruptured aneurysm are 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. If you know that you have an aneurysm and start to experience these symptoms, go to the emergency room immediately.

How is it Treated?

Aneurysms less than 5 centimeters in diameter are monitored regularly with yearly or bi-yearly ultrasounds or CT scans. Blood pressure control and tobacco cessation are imperative. Your doctor may also recommend that you avoid heavy lifting or straining. Surgery is considered for aneurysms 5 centimeters or greater in diameter. Surgical options include an open surgical technique (replacing the aneurysm with a synthetic tube graft) or a less invasive procedure called endovascular stent grafting.

Aortic Aneurysm Repair

Open surgery for aortic aneurysm repair has been performed for over 40 years with a low risk of complications and excellent success rate in well-selected patients. Its aim is to replace the aneurysmal segment of the aorta.

General anesthesia is required for the procedure. An incision is made in the abdomen, and the aorta is clamped to temporarily stop blood flow. The aneurysm is opened, and then a woven tube graft made of synthetic (man-made) material, such as Dacron, is sewn to the ends of the normal aorta above and below the aneurysm. This graft will replace the aortic aneurysm, allowing normal blood flow to the legs and other organs after surgery. The procedure is done under a general anesthetic and takes approximately 2 to 4 hours. In-hospital recovery from the surgery takes from 4 to 7 days.

Risks of surgery include heart attack, abnormal heart rhythm, blood loss requiring transfusion, bowel ischemia, renal failure and emboli to the feet. In some cases, endovascular aortic aneurysm repair (EVAR), a less invasive procedure, is possible as an alternative to open surgery.

Endovascular Aortic Aneurysm Repair (EVAR)



Endovascular stent grafting is a less invasive procedure originally introduced about 10 years ago to treat aneurysms in patients who were not candidates for open surgery because of the severity of their other medical problems. Studies suggest that EVAR carries a low risk of perioperative complications and has a good procedural success rate in selected patients.

Endovascular stent graft repair is performed in the operating room under a light general or epidural anesthetic. Catheters and wires are inserted into the femoral (leg) arteries through small incisions in the groins. A stent graft is a synthetic tube graft supported by metal stents. It is deployed inside the aorta from sheaths inserted through the femoral arteries. This placement is guided by continuous x-ray (fluoroscopy). The stent graft is secured to the normal aorta above the aneurysm and to the normal iliac (pelvic) arteries below the aneurysm. This fixation creates an “internal bypass,” preventing blood flow into the aneurysm by shunting the blood through the stent graft and into the legs. With the aneurysm excluded from circulation, it does not grow and does not rupture.

EVAR is associated with decreased requirement for blood transfusions and shorter in-hospital recovery time when compared with conventional open surgical repair. Patients generally leave the hospital 1 to 2 days after surgery. EVAR may also have a lower risk of heart and lung complications. It does, however, require fluoroscopy, which exposes the patient to radiation and x-ray dye (contrast). Postoperatively, patients are followed with serial imaging studies (ultrasound or CT scan).

Not all aneurysms can be fixed by the endovascular approach. The anatomy (shape) of the aneurysm determines whether a stent graft is possible.