A systematic review and meta-analysis of the long-term outcomes of endovascular versus open repair of abdominal aortic aneurysm

Abstract

Objective: This study synthesized the literature comparing the long-term (5-9 years) and very long-term (≥10 years) all-cause mortality, reintervention, and secondary rupture rates between endovascular aneurysm repair (EVAR) and open surgical repair (OSR) of abdominal aortic aneurysm (AAA).

Methods: MEDLINE, Embase, and CENTRAL databases were searched from inception to May 2018 for studies comparing EVAR to OSR with a minimum follow-up period of 5 years. Study selection, data abstraction, and quality assessment were conducted by two independent reviewers, with a third author resolving discrepancies. Study quality was assessed using the Cochrane and Newcastle-Ottawa scales. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using random-effects models. Heterogeneity was quantified using the I² statistic, and publication bias was assessed using funnel plots.

Results: Our search yielded 3431 unique articles. Three randomized controlled trials and 68 observational studies comparing 151,092 EVAR to 148,692 OSR patients were included. Inter-rater agreement was excellent at the screening (κ = 0.78) and full-text review (κ = 0.89) stages. Overall, the risk of bias was low to moderate. For long-term outcomes, 54 studies reported all-cause mortality (n = 203,246), 23 reported reintervention (n = 157,151), and 4 reported secondary rupture (n = 150,135). EVAR was associated with higher long-term all-cause mortality (OR, 1.19; 95% CI, 1.06-1.33; P = .003, I² = 91%), reintervention (OR, 2.12; 95% CI, 1.67-2.69; P < .00001, I² = 96%), and secondary rupture rates (OR, 4.84; 95% CI, 2.63-8.89; P < .00001, I² = 92%). For very long-term outcomes, 15 studies reported all-cause mortality (n = 48,721), 9 reported reintervention (n = 7511), and 1 reported secondary rupture (n = 1116). There was no mortality difference between groups, but EVAR was associated with higher reintervention (OR, 2.47; 95% CI, 1.71-3.57; P < .00001, I² = 84%) and secondary rupture rates (OR, 8.10; 95% CI, 1.01-64.99; P = .05). Subanalysis of more recent studies, with last year of patient recruitment 2010 or after, demonstrated no long-term mortality differences between EVAR and OSR.

Conclusions: EVAR is associated with higher long-term all-cause mortality, reintervention, and secondary rupture rates compared with OSR. In the very long-term, EVAR is also associated with higher reintervention and secondary rupture rates. Notably, EVAR mortality has improved over time. Vigilant long-term surveillance of EVAR patients is recommended.

Keywords: Abdominal aortic aneurysm (AAA); Endovascular aneurysm repair (EVAR); Long-term outcomes; Open surgical repair (OSR); Systematic review.