MINNEAPOLIS — Abdominal aortic aneurysms (AAA) can be deadly if they rupture, but a study by the Department of Veterans Affairs has found it is better not to correct the problem with surgery unless the aneurysm exceeds a certain size. The common hazards of surgery can be the greater threat unless the aneurysm is larger than 5.5 centimeters in diameter, according to findings published in the May 9 issue of the New England Journal of Medicine.
"Repair of a smaller aneurysm does not benefit the patient and may present greater risks than the aneurysm itself," said lead author Frank Lederle, M.D., of the Minneapolis VA Medical Center. "Because we know that most of these smaller aneurysms will never rupture, our ultimate goal is to repair the AAAs that will burst and no others."
The abdominal aorta is part of the aorta, a major artery that delivers blood from the heart to internal organs in the lower part of the body. Aneurysms are blood-filled dilations that occur when the walls of the aorta weaken and bulge. They are fairly common, particularly among older men who have smoked, but most of them never rupture.
All patients face certain risks in surgery, including potentially deadly complications such as heart failure or infection. This raises the question whether it is a good idea to risk repairing something that may not pose a significant threat.
Dr. Lederle and his colleagues believe that guidelines based on their findings could result in at least 20 percent fewer repairs. This could mean fewer deaths and better treatment options for patients. Researchers also suspect the guidelines could be cost effective as well. The study also demonstrated an extraordinarily high surgery-survival rate at the 16 participating VA hospitals -- nearly 98 percent. Dr. Lederle hopes this will convince doctors to restrict AAA repair.
"The survival rate was one of the highest ever reported, " he said. "We can attribute this to selecting good surgical candidates, and the skill of the VA surgical and post-surgical teams. If smaller AAA surgery isn’t advisable with our excellent surgery-survival rates, it’s hard to imagine it being justifiable anywhere else." The VA Cooperative Studies Program (CSP) funded this study. VA research will continue to investigate new ways of lessening risk among patients who need AAA surgery by studying safer procedures.
An upcoming CSP study will compare it with endovascular repair -- a new method that repairs the AAA from inside the aorta through a small incision in the groin. Researchers hope to determine which repair method has the best long-term results. The study will begin this summer at 40 VA medical centers.
Research is an intrinsic part of the VA mission that benefits veterans and non-veterans.
For Information Contact: Linda Duffy, 612-725-2102, Linda.Duffy@med.va.gov
Journal
New England Journal of Medicine