Infrarenal abdominal aortic aneurysm--indications for surgery and survival

Objective: Elective operation is an established therapy in the management of infrarenal aortic aneurysms. Surgery has an acceptable low risk in the presence of experienced surgeons and anaesthetists. Indication for surgery nevertheless remains a difficult problem, because diagnostic procedures and evaluation of different criteria do not exactly predict the likelihood of rupture. Indication for surgery is moreover dependent on operative mortality and late survival. This study analyses early and late results associated with the repair of abdominal aortic aneurysms in our institution in Hamburg and comments on indication for elective surgery.

Methods: Life-Table analysis was used to determine survival rate. Calculation of expected prevalence of abdominal aortic aneurysms in the Hamburg population was based on demographic statistics and results in the literature.

Results: Between January 1981 and April 1995 1242 patients underwent abdominal aortic aneurysm repair, 1018 electively, 224 for ruptured aneurysm. Operative mortality was 4% and 50% respectively. The survival rate after elective operation was 64% at 5, 43% at 10 and 35.4% at 14 years, while after emergency surgery for ruptured aneurysm it was 40% at 5, 31.9% at 10 and 29.8% at 14 years. The survival rate of survivors after repair for ruptured aneurysms is similar to that after elective surgery. Over a 13 years period the rate of ruptured aneurysms did not decrease. Comparison of surgical data and calculated prevalence data show that a three times higher operative activity is requested to repair all occurring abdominal aortic aneurysms larger than 5 cm in diameter.

Conclusions: In order to reduce the still high mortality associated with aneurysm rupture there is still a need for more prophylactic surgery.