Abdominal Aortic Aneurysm Disease: The Silent Killer

Posted By SHL Librarian

Presented by: Ronald L. Dalman, M.D.
Professor of Surgery
Stanford University Medical Center
September 26, 2007

Lecture Overview:
There has been considerable interest recently in public education and screening for Abdominal Aortic Aneurysm (AAA) after a front page Wall Street Journal article about it received the Pulitzer Prize for Health Reporting a few years ago. There are 30,000 deaths in the US each year related to AAA, a condition that years ago claimed the life of Albert Einstein and George C. Scott. AAA occurs when a portion of the aorta becomes worn out due to the loss of elastin, a protein that promotes tension in the skin and blood vessels. The cause of an aneurysm can be genetic but smoking is the single highest risk factor in causing AAA. Dr. Dalman provided a thorough overview of the definition and clinical management for small and large AAA. While there is no clear and well-proven treatment for small AAAs (between 3 and 5.5 cm), there are surgical options for the larger, more worrisome kind of aneurysm (5.5 cm or larger).

Who?

  • AAA is among the top 15 leading causes of death in mature adults
  • 6% of men
  • 1.5 % of women

What and Where?

  • An Abdominal Aortic Aneurysm (AAA) is an enlargement of the aorta. The aorta, which starts in the heart and moves through the left side of the chest, through the diaphragm and into the abdomen, is the largest artery in the body and supplies blood to the entire body.
  • An AAA occurs in the space between the lowest part of the sternum (the blood supply to the kidneys and other organs) and the part of the aorta where it splits into the iliac arteries (supplying blood to the legs).
  • According to Dr. Dalman, there are usually six years between the identification of a 3 cm AAA and the recommendation for surgery.
  • The most common symptom is pain, often confused with back pain.
  • The growth rate is about .4 cm annually, which translates to about two and a half years for an AAA to grow a centimeter.

There are two types of surgeries to treat AAA:

  1. Abdominal aortic aneurysm open repair
    A large incision is made in the abdomen to directly visualize the abdominal aorta and repair the aneurysm. A cylinder-like tube called a graft may be used to repair the aneurysm. Grafts are made of various materials such as Dacron (textile polyester synthetic graft) or polytetrafluoroethylene (PTFE, non-textile synthetic graft). This graft is sewn to the aorta, connecting one end of the aorta at the site of the aneurysm to the other end. The open repair is considered the surgical standard for an abdominal aortic aneurysm repair.
  2. Endovascular aneurysm repair (EVAR)
    EVAR is a procedure that requires only small incisions in the groin along with the use of x-ray guidance and specially-designed instruments to repair the aneurysm. With the use of special endovascular instruments and x-ray images for guidance, a stent-graft is inserted via the femoral artery and advanced up into the aorta to the site of the aneurysm. A stent-graft is a long cylinder-like tube made of thin metal mesh framework (stent), while the graft is made of various materials such as Dacron or polytetrafluoroethylene (PTFE). The graft material may cover the stent. The stent helps to hold the graft open and in place.
    For patient education information and additional information on surgical repair, please visit:
    http://www.vascularweb.org/

When?
AAAs that require treatment are most likely to occur in people over 55. Often an AAA is identified when a patient is screened with ultrasound or CT scan for another condition. People with a family history and with symptoms may be screened at any time depending on a doctor’s recommendation.

Why?
The highest risk factor for AAA is smoking (a risk of 5 on a scale of 1-5) and genetics (a risk of 1.5)

For More Information:

Stanford Health Library can do the searching for you. Send us your medical questions.

Division of Vascular Surgery at Stanford University
http://vascular.stanford.edu/
The Division of Vascular Surgery at Stanford aims to provide a model of clinical and scientific excellence in the diagnosis and treatment of vascular diseases, to deliver the highest quality of care to our patients by a team of dedicated surgeons and nurses, and to achieve these goals within an environment that fosters compassion and respects the humanity of the individual person.

Link to Clinical Trial information at Stanford Medical Center:
Abdominal Aortic Aneurysms: Simple Treatment or Prevention (AAA: STOP)
http://aaastop.stanford.edu/
If you are a patient with a small abdominal aortic aneurysm (<5.5 cm in size) and over the age of 50, you may qualify for participation in the AAA: STOP study. The goal of AAA: STOP is to gather information on AAA risk factors and determine whether an exercise program modifies the progression of AAA disease. Please contact Julie White at Stanford University for more information on this research program by phone at (650) 498-6039 or by email at jljwhite@stanford.edu.

Medicare AAA Screening Benefit
http://www.vascularweb.org/patients/medicarescreening/index.html
The Screening Abdominal Aortic Aneurysms Very Efficiently (SAAAVE) Act provides for a free, one-time AAA screening as part of the “Welcome to Medicare” physical exam.
Men and women with a family history of AAA and men who have smoked at least 100 cigarettes during their life qualify for the Medicare screening.

Dr. Dalman’s Stanford Profile:
http://med.stanford.edu/profiles/Ronald_Dalman/