Long-Term Outcomes Following Elective Repair of Intact Abdominal Aortic Aneurysms A Comparison Between Open Surgical and Endovascular Repair Using Linked Administrative and Clinical Registry Data

Objective:Compare long-term mortality, secondary intervention and secondary rupture following elective endovascular aneurysm repair (EVAR) and open surgical repair (OSR). Background:EVAR has surpassed OSR as the most common procedure used to repair abdominal aortic aneurysm (AAA), but evidence regarding long-term outcomes is inconclusive. Methods:We included patients in linked clinical registry and administrative data undergoing EVAR or OSR for intact AAA between January 2010 and June 2019. We used an inverse probability of treatment-weighted survival analysis to compare all-cause mortality, cause-specific mortality, secondary interventions and secondary rupture, and evaluate the impact of secondary interventions and secondary rupture on all-cause mortality. Results:The study included 3460 EVAR and 427 OSR patients. Compared to OSR, the EVAR all-cause mortality rate was lower in the first 30 days [adjusted hazard ratio (HR) = 0.22, 95% confidence interval (CI) 0.140.33], but higher between 1 and 4 years (HR = 1.29, 95% CI 1.12-1.48) and after 4years (HR = 1.41, 95% CI 1.23-1.63). Secondary intervention rates were higher over the first 30 days (HR = 2.26, 95% CI 1.11-4.59), but lower between 1 and 4years (HR = 0.59, 95% CI 0.48-0.74). Secondary aortic intervention rates were higher across the entire follow-up period (HR = 2.52, 95% CI 2.06-3.07). Secondary rupture rates did not differ significantly (HR = 1.06, 95% CI 0.73-1.55). All-cause mortality beyond 1 year remained significantly higher for EVAR after adjusting for any secondary interventions, or secendary rupture Conclusions:EVAR has an early survival benefit compared to OSR. However, elevated long-term mortality and higher rates of secondary aortic interventions and subsequent aneurysm repair suggest that EVAR may be a less durable method of aortic aneurysm exclusion.