ABSTRACT
INCIDENCE Aortic aneurysms are a pathological condition characterized by dilatation of the aorta and involve the expansion and thinning of all layers o f the arterial wall (1,2; see Figure 1). Aortic aneurysms are the thirteenth leading cause o f death in the United States (3), which means that about 13,000 individuals die every year from the rupture o f an aortic aneurysm. In the United States in 1984, 1.2% o f all deaths in men and 0.6% of all deaths in women over the age o f 65 were due to aortic aneurysms (4). Abdominal aortic aneurysms (AAAs) are responsible for about 1.3% o f the deaths among men aged over 50 years in both the United Kingdom and Sweden, and the proportion has been increasing (5,6). A study o f 22,765 autopsies in Finland during the years 1959 to 1979 revealed an abdominal aortic aneurysm in 193 individuals, correspond ing to a prevalence o f 0.85% (7). Most AAAs do not produce symptoms until they suddenly rupture. Aortic aneurysms most commonly occur in the infrarenal segment o f the abdominal aorta, and most patients with an AAA do not have aneurysms in the other parts o f aorta (8).
