Editor's Choice – Mortality is High Following Elective Open Repair of Complex Abdominal Aortic Aneurysms

Objective: To evaluate the 30 day mortality of elective open complex abdominal aortic aneurysm (cAAA) repair and identify factors associated with death. Methods: This was a retrospective cohort study using a Targeted Vascular Module from the American College of Surgeons National Surgical Quality Improvement Program (NSQIP). All patients undergoing elective repair for juxta- and suprarenal abdominal aortic aneurysm (AAA), or type IV thoraco-abdominal aneurysms (TAAA) from 2011 to 2017 were identified. Thirty day mortality and complication rates for open repair were established. A comparison endovascular aneurysm repair (EVAR) group was extracted from the same time period, and inverse probability weighting was applied for comparison. Logistic regression was used to identify factors independently associated with open repair mortality. Results: Of the 957 patients who underwent an elective open cAAA repair over the study period, 65 (6.8%) died. The mean age of the patient was 71.3 ± 8.0 years. The distribution by aneurysm type was 605 juxtarenal AAA (28 deaths, 4.6%); 284 suprarenal AAA (16 deaths, 9.5%), and 68 type IV TAAA (10 deaths, 14.7%). During the same time period, there were 1149 endovascular repairs for cAAA, with 43 deaths (3.7%). After inverse probability weighting and weighted logistic regression, open repair 30 day mortality yielded an OR 1.9, 95% CI 1.2–3.1, p =.01 compared with EVAR. Factors independently associated with death included more proximal extent aneurysm (referent [ref]: juxtarenal: OR 2.0 per extent increase, 95% CI 1.4–3.0, p <.001), BMI < 18.5 (OR 4.0, 95% CI 1.6–10.1, p =.003), history of severe chronic obstructive pulmonary disease (COPD) (OR 2.6, 95% CI 1.5–4.4, p =.001), more severe chronic kidney disease (CKD) (ref: none/mild): OR 1.9, 95% CI 1.2–2.8, p =.004), and age (OR 1.06/year, 95% CI 1.02–1.09, p =.002. Conclusion: The 30 day mortality was 4.6% for juxtarenal AAA, 9.5% for suprarenal AAA, and 14.7% for type IV TAAA. The open repair odds of 30 day mortality was nearly twice that of endovascular repair for cAAA. Independent associations with death included BMI <18.5, more severe CKD level, more proximally extending aneurysm, age, and history of advanced COPD.