EARLY AND LATE OUTCOME OF SURGICAL REPAIR FOR SMALL ABDOMINAL AORTIC-ANEURYSMS - A POPULATION-BASED ANALYSIS

Purpose: Whether small abdominal aortic aneurysms (AAAs) (less-than-or -equal-to 5 cm in diameter) should be repaired early to enhance late s urvival remains controversial. Long-term population-based data on the surgical outcome for small AAAs may help to establish practice guideli nes until randomized clinical trials are completed. Methods: To examin e an entire community experience with small AAAs, we conducted a popul ation-based analysis of the recognition, reasons for operation, periop erative mortality rates, and late survival in Olmsted County, Minnesot a. Results: The incidence of recognized small AAAs increased thirtyfol d during a 30-year period. The propensity to repair small AAAs also in creased during the same period. Eventually one third of small AAAs wer e repaired. The primary reasons for surgical consultation and operatio n were presence of the aneurysm (49%), expansion on serial examination (28%), nonspecific abdominal or back symptoms (18%), and excessive pa tient anxiety about the aneurysm (5%). Community operative mortality r ates for small AAAs were low (2.6%) compared with those for large aneu rysms (5.5%) (p = 0.65). However, the observed 5-year survival rate fo r the group undergoing repair of small aneurysms was 62%, which was si gnificantly less than the 83% expected survival for the general popula tion (p < 0.05). Relative survival for the operated small and large an eurysms was similar. The primary cause of death for both groups was my ocardial infarction. Conclusions: The results of our population-based analysis indicate that early operative results for elective repair of small AAAs are excellent, but late survival remains significantly impa ired by coronary heart disease. Consequently, our data question whethe r early repair of small AAAs will enhance late survival. Until randomi zed clinical trials on management of small AAAs are completed, most sm all AAAs should be monitored for expansion and operated on electively when they approach or enter the range of 5 to 6 cm in good-risk patien ts.