Optimal selection of patients for elective abdominal aortic aneurysm repair based on life expectancy

Abstract

Elective abdominal aortic aneurysm (AAA) repair is beneficial when rupture is likely during a patient's expected lifetime. The purpose of this study was to identify predictors of long-term mortality after elective AAA repair for moderately sized AAAs (<6.5-cm diameter) to identify patients unlikely to benefit from surgery. We analyzed 2367 elective infrarenal AAA (<6.5 cm) repairs across 21 centers in New England from 2003 to 2011. Our main outcome measure was 5-year life-table survival. Cox proportional hazards analysis was used to describe associations between patient characteristics and 5-year survival. During the study period, 1653 endovascular AAA repairs and 714 open AAA repairs were performed. Overall, 5-year survival rates were similar by procedure type (75% endovascular repair, 80% open repair; P = .14). Advanced age ≥75 years (hazard ratio [HR], 2.0; P < .01) and age >80 years (HR, 2.6; P < .01), coronary artery disease (HR, 1.4; P < .04), unstable angina or recent myocardial infarction (HR, 4.6; P < .01), oxygen-dependent chronic obstructive pulmonary disease (HR, 2.7; P < .01), and estimated glomerular filtration rate <30 mL/min/1.73 m(2) (HR, 2.8; P < .01) were associated with poor survival. Aspirin (HR, 0.8; P < .03) and statin (HR, 0.7; P < .01) use were associated with improved survival. We used these risk factors to develop risk strata for low-risk, medium-risk, and high-risk groups with survival, respectively, of 85%, 69%, and 43% at 5 years (P < .001). More than 75% of patients with moderately sized AAAs who underwent elective repair in our region survived 5 years, but 4% were at high risk for 5-year mortality. Patients with multiple risk factors, especially age >80 years, unstable angina, oxygen-dependent chronic obstructive pulmonary disease, and estimated glomerular filtration rate <30 mL/min/1.73 m(2), are unlikely to achieve sufficient long-term survival to benefit from surgery, unless their AAA rupture risk is very high.