Aortic Aneurysm

Aortic Aneurysm

An aneurysm is the bulging of a blood vessel, usually an artery, indicating weakness or thinning of the vessel wall. The most common aneurysm is an aortic aneurysm. The aorta is the main artery in your body. It starts at the heart and transports blood through the chest and belly. At the level of the belly button, the aorta splits into two arteries to deliver blood to each leg.

The most common location for an aortic aneurysm is in the abdomen just below the kidneys, where the aorta normally measures 1.5-2.5 centimeters (about one inch) wide. If the abdominal aorta bulges to 3 centimeters or more, it is considered to be an abdominal aortic aneurysm (AAA, or “triple A).” Like a balloon, the larger an aneurysm gets, the greater the risk of the artery bursting (rupture). Most people with a ruptured AAA do not survive due to massive sudden internal bleeding.

In general, aneurysms do not cause symptoms and are found most often on testing done for other reasons. The US Centers for Medicare and Medicaid Services (CMS) will cover one ultrasound study for male ever smokers aged 65-75 years or anyone (men >55 and women >65) with family history of aneurysm (SAAAVE Act 2007) to screen for AAA. After an aneurysm has been found, if it does not yet need surgery it should continue to be checked every so often with repeat ultrasound to watch for aneurysm growth.

Risk factors for AAA

  • Male gender
  • Age over 65
  • High blood pressure
  • Coronary artery disease
  • Family history of aneurysm
  • Genetics
  • Past or present tobacco use (more than 100 cigarettes)

The accepted guidelines recommend fixing AAAs when they reach 5.5 centimeters or more in size. At five centimeters, the risk of rupture is 1-2 percent yearly; for 6-7 centimeters, the risk is 3-5 percent yearly, and >7 centimeters, the risk is 10-20 percent yearly. There are two ways of fixing aneurysms: open surgery and endovascular stenting. The choice of approach depends on the aneurysm location and anatomy, and the patient’s health and life expectancy.

Open Surgery for AAA

Some aneurysms are best fixed through standard open surgery. This can be done through an incision down the center of the belly, or through an angled incision along the left side of the abdomen. Blood flow through the aneurysm is temporarily stopped with clamps on the aorta above and below the aneurysm. The aneurysm is opened lengthwise, and a replacement aorta (usually a tube made of polyester) is hand sewn to the artery above and below the aneurysm. The aneurysm wall is then closed over the front of the graft to protect it. The graft is permanent, and over time, the body grows the normal inner lining of an artery inside it.

This surgery takes two to four hours and is done with the patient completely asleep on a breathing machine (general anesthetic). Some people may require a blood transfusion. After surgery, patients are usually monitored in Intensive Care for at least a day or two. The average hospital stay is three to five days, depending on pain control, how long it takes for the intestines to resume normal function and any other medical conditions.

Endovascular Aneurysm Repair (EVAR) or EndoGraft

Endovascular Aneurysm Repair (EVAR) is a minimally invasive alternative to open surgery for the repair of abdominal aortic aneurysms. This approach was initially introduced in the 2000s for people who were too sick to have open aneurysm repair, but it now has become the most common operation for the majority of patients with aneurysms that are located below the kidneys. However, treatment must always be individualized, and some people are not good candidates for EVAR for various reasons.

The concept of EVAR involves relining the inside of the artery with stents that are covered by material so that the aneurysm is no longer in contact with pressurized blood. This prevents further aneurysm bulging and reduces the chances of rupture. The covered stents are inserted through the arteries, usually from the groin, using wires and catheters through the arteries and X-ray guidance. Over time, the wall of the aneurysm should stay the same size as it was at the time of surgery, or sometimes it will shrink down around the graft.

On average, EVAR takes about two to three hours. It can be done with a general anesthetic or with a combination of local numbing medicine and sedating medicines given through an IV. Blood transfusion is rarely needed, and most of the time, only an overnight hospital stay is expected.

Risks and Benefits of EVAR vs Open Surgery for AAA

Open surgery is considered a more major operation than EVAR because of the stress on the heart and lungs that occurs with the opening of the abdomen and clamping of the aorta. However, the endovascular option also has risks that are specific to the technology, and that may have long-term impact. When done in the right patients, open and endovascular aneurysm repair are both excellent in preventing aneurysm-related death.

Potential risks for both open and endovascular aneurysm repair include:

  • Wound infection
  • Bleeding
  • Kidney failure

Potential risks primarily with open aneurysm repair include:

  • Respiratory failure
  • Bowel injury or blockage
  • Hernia
  • Heart attack

Potential risks primarily with endovascular aneurysm repair include:

  • Artery dissection or thrombosis (injury in the inner wall of the artery)
  • Stroke
  • Distal embolization (clot or atherosclerotic plaque that travels to the legs or other organs)
  • Endoleak and need for secondary procedures

Post-Operative Expectations

With open aneurysm repair, recovery is expected to take 2-4 weeks, where energy level and appetite may not be normal. Pain along the incision will last at least a couple of weeks, and numbness around the incision can take months to go away. Walking and light exercise is encouraged, but heaving lifting (>10 pounds) is not allowed for the first 4-6 weeks to try and prevent the development of a hernia.

For endovascular aneurysm repair, patients frequently feel under the weather (tired, achy, decreased appetite, possibly low-grade fever) for the first week. Lifting (>10 pounds) or straining is discouraged for a week, and otherwise all normal activities are fine.

After surgery, whether open or endovascular, the repair should be monitored over time. For an open repair, this can be done with an ultrasound every few years. For EVAR, this follow-up imaging is more frequent and involves initially a CT scan, and then usually ultrasound once a year.

Our team brings vast experience performing standard and complex EVAR procedures with a low complication rate.