Abdominal Aortic Aneurysm
Introduction
Abdominal Aortic Aneurysm (or AAA) is a condition where the large blood vessel that runs down the back is enlarged. As this occurs, the wall also gets thinner, placing the aorta at increasing risk for rupture.
Frequently Asked Questions: FAQ's
1. What causes an AAA?
Answer: An AAA is usually the result of atherosclerosis, or hardening of the arteries. In patients who get atherosclerosis, one of the body's first adaptive responses is to enlarge to account for the narrowing that occurs. As further hardening occurs in most blood vessels, the enlargement is minimal and stops, allowing the artery to pregress to occlusion. In patients who develop aneurysms, the aorta does not stop dilating. This is especially so in patients who have the tendancy in their family history.
Cigarette smoking and high blood pressure are essential risk factors in patients who get AAAs.
2. Why should I be concerned?
Answer: As an aneurysm enlarges, it can rupture with increasing frequency. Half of patients who rupture their AAA never reach medical attention. And about half of those do not survive treatment. The risk of rupture dramatically increases once an AAA reaches 5 cm. in diameter. Here it is around 25% at 5 years. At 7 cm. the risk of rupture is over 60% at 5 years.
3. How do I know if I have an AAA?
Answer: Your primary doctor may feel it in your abdomen on a routine screeing physical exam. Other AAAs are found incidentally on Xrays or Ultrasounds for other reasons. It also can also show up on a CT Scan of the abdomen.
4. Is there any warning of a rupture?
Answer: Unfortunately, most AAAs rupture suddenly. A few patients may experience new severe tearing like back pain, but still not yet be ruptured. A patient with a pulsitile abdominal mass, back pain and low blood pressure has a rupturing AAA until proven otherwise.
5. How can an AAA be treated.
Answer: An AAA must be excluded from the blood stream and pressure. The gold standard is a conventional operation to remove the AAA and replace that part of the aorta. (see one of two Animations ,{ #2} of a AAA repair). An exciting new method involves placing a graft right within the aorta with various catheters to exclude the AAA.
6. What are the differences in the AAA procedure?
Answer: A standard operation has proven durability of 20 plus years with very minimal consequences of longterm problems. It does involve an operation with an open repair that typically can require a 6-9 day hospital stay. For most patients, the operative risk is between two and four percent for mortality. The endovascular repair is still investigational, with the endografts still under FDA Review. While an endograft has the potential to shorten hospital stays to 1-2 days, and shorten recovery to only days, there are some issues to consider. Most centers placing Endografts still are reporting 1-2% operative mortalities around the procedure. This is because of patient risk factors, such as coronary artery disease, that cannot be reduced to zero. AAAs repaired by endografting have not been followed by more than 5 years, and this is only the first few placed. Most centers have at best 2 years follow-up. Even then, all endograft patients require expensive testing every three months to confirm the repair is still good. Endografts have developed delayed leaks (called 'endoleak') in up to 15-18% of reported patients. Some endoleaks are treatable, some are not. This has resulted in rupture of the very AAA it was supposed to treat! While this is not common, it remains a long term risk that is poorly defined to those patients with an endograft.
7. Which procedure should I have for my AAA?
Answer: Any patient needs to talk throughly about the options with the surgeon or team who would do either procedure. At the Jacksonville Vascular Institute, we feel our multidisciplinary approach maximizes your options. We have experience in placing custom measured endografts for AAA, allowing some patients to be treated who might not otherwise have anatomy applicable to the endograt technique. Our surgeons and radiologists are highly trained, continuing our education about new therapies on a regular basis so we can offer the latest and best therapies. For conventional repair, our surgeons have an accumulated experience of over 23 years treating AAAs.
In our opinon, a patient who is somewhat younger with a prolonged life expectancy and good perioperative risk is best served by the proven long term solution: Open conventional repair. However, our team is well suited if a patient has particularly high risk for an open repair to instead treat the AAA with an Endovascular repair. One of our physicians would be able to better answer questions with a face to face evaluation and consultation.
We at the PVSS hope this information as answered what may be some of your questions about abdominal aortic aneurysms and their treatment.
Sincerely,
Henry C. Veldenz, M.D., F.A.C.S., for the PVSS