DOCTOR'S VIEW ARCHIVE
Is It Safe to Just Monitor An Abdominal Aortic
Aneurysm?
An aneurysm is a swelling of an artery due to weakness in the vessel
wall. It is a common cause of sudden death and often provides no
warning signs or symptoms.
Currently, the only method to prevent rupture of an aneurysm is
surgical repair of the vessel. But, because of the risks involved in
surgery, the aneurysm is generally allowed to reach a size for which
the risk of rupture outweighs the risk of surgery.
Is it safe to monitor an abdominal aneurysm rather than have
surgery right away? A report in the medical journal The Lancet on
November 21, 1998 bears upon this potentially life-and-death
decision.
The Lancet report comes from the investigators in the UK (United
Kingdom) Small Aneurysms Trial. They studied whether surveillance by
ultrasonography (ultrasound) of small aneurysms before surgery to
monitor their size would affect the long-term survival of patients
who underwent early surgery.
Patients with small abdominal aneurysms were monitored. The aneurysms were from 4.0 to 5.5 cm in diameter. ( For aneurysms greater
than 5.5 cm in diameter, surgeons favor an operation).
The patients were randomly assigned to one of two modes of
management:
- Surgery in which the vessel was repaired with a graft; or
- Monitoring with ultrasonography until the size of the aneurysm
was 5.5 cm or more, grew by at least 1.0 cm per year, or became
tender, after which patients were offered surgery.
The patients were followed up for an average of 4.6 years.
The conclusion of the UK report is that generally the use of
"ultrasonographic surveillance for small abdominal aortic aneurysms
is safe, and early surgery does not provide a long-term survival
advantage".
The UK trial is important because "it has replaced many
assumptions with facts, and the findings will transform the way
patients and clinicians make decisions on the management of (sic)
aortic aneurysms", note Drs. Rene Prêtre and Marko Turina from
Zurich, Switzerland in a Commentary published in the same issue of
The Lancet.
As the poet Robert Frost wrote (in another context, to be sure), "And wait to watch the water clear, I may." It would seem safe,
in regard to small abdominal aortic aneurysms, to "wait to watch the
water clear".
Please visit our Abdominal Aortic
Aneurysm Center for more information.
Source: The Lancet, vol. 352, no. 9141, Nov. 21, 1998.
Last Editorial Review: 4/1/2002