Comparison of Outcomes in Elective Endovascular Aortic Repair vs Open Surgical Repair of Abdominal Aortic Aneurysms

Importance: Knowledge regarding the long-term outcomes of elective treatment of abdominal aortic aneurysm (AAA) using endovascular aortic repair (EVAR) is increasing. However, data with greater than 10 years' follow-up remain sparse and are lacking from population-based studies. Objective: To determine the long-term outcomes of EVAR compared with open surgical repair (OSR) for elective treatment of AAA. Design, Setting, and Participants: This retrospective, population-based cohort study used linked administrative health data from Ontario, Canada, to identify all patients 40 years and older who underwent elective EVAR or OSR for AAA repair from April 1, 2003, to March 31, 2016, with follow-up terminating on March 31, 2017. A total of 17683 patients were identified using validated procedure and billing codes and were propensity score matched. Analysis was conducted from June 26, 2018, to January 16, 2019. Exposures: Elective EVAR or OSR for AAA. Main Outcomes and Measures: The primary outcome was overall survival. Secondary outcomes were major adverse cardiovascular event-free survival, defined as being free of death, myocardial infarction, or stroke; reintervention; and secondary rupture. Results: Among 17683 patients who received elective AAA repairs (mean [SD] age, 72.6 [7.8] years; 14286 [80.8%] men), 6100 (34.5%) underwent EVAR and 11583 (65.5%) underwent OSR. From these patients, 4010 well-balanced propensity score-matched pairs of patients were defined, with a mean (SD) age of 73.0 (7.6) years and 6583 (82.1%) men. In the matched cohort, the mean (SD) follow-up was 4.4 (2.7) years, and maximum follow-up was 13.8 years. The overall median survival was 8.9 years. Compared with OSR, EVAR was associated with a higher survival rate up to 1 year after repair (91.0% [95% CI, 90.1%-91.9%] vs 94.0% [95% CI, 93.3%-94.7%]) and a higher major adverse cardiovascular event-free survival rate up to 4 years after repair (69.9% [95% CI, 68.3%-71.3%] vs 72.9% [95% CI, 71.4%-74.4%]). Cumulative incidence of reintervention was higher among patients who underwent EVAR compared with those who underwent OSR at the 7-year follow-up (45.9% [95% CI, 44.1%-47.8%] vs 42.2% [95% CI, 40.4%-44.0%]). Survival analyses demonstrated no statistically significant differences in long-term survival, reintervention, and secondary rupture for patients who underwent EVAR compared with those who underwent OSR. Kaplan-Meier analysis suggested superior long-term major adverse cardiovascular event-free survival among patients who underwent EVAR compared with those who underwent OSR (32.6% [95% CI, 26.9%-38.4%] vs 14.1% [95% CI, 4.0%-30.4%]; stratified log-rank P <.001) during a maximum follow-up of 13.8 years. Conclusions and Relevance: Endovascular aortic repair was not associated with a difference in long-term survival during more than 13 years' maximum follow-up. The reasons for these findings will require studies to consider specific graft makes and models, adherence to instructions for use, and types and reasons for reintervention.