The natural history of abdominal aortic aneurysm

The outcome of 65 patients with unoperated abdominal aortic aneurysms (AAA) were reviewed in order to evaluate the natural history and "quality of life". An estimated cumulative life-table was constructed. Of the 65 patients admitted to the department (from 1972 to 1984), 52 were discharged from the hospital and not operated on because of concurrent medical disorders. These patients were divided into two groups: 34 with asymptomatic AAA on admission to the department and 18 with symptoms. During follow-up, 38 patients died, 71% in the asymptomatic and 78% in the symptomatic group. Less than 50% of all the patients died of concurrent disease. Of the patients in the asymptomatic group with a small aneurysm, 38% died of rupture of AAA. As AAA is a disease with a high mortality, the co-existent medical disorders must be very "serious" if the patient is not to be offered an operation. Even small, asymptomatic AAAs may rupture and should be operated on. No factor seemed to predict the natural history for the individual patient. A score system, for example, the "Boston score", is recommended. This would facilitate good objective assessment of the patients entering into future studies and the evaluation of "survival curves" will improve.