Systematic Review and Meta-Analysis of Outcomes of Open and Endovascular Repair of Ruptured Abdominal Aortic Aneurysm in Patients with Hostile vs. Friendly Aortic Anatomy

Abstract

Objective: To investigate the effect of hostile aortic anatomy on the outcomes of endovascular and open repair for ruptured abdominal aortic aneurysm (AAA).

Methods: Electronic bibliographic sources (MEDLINE, EMBASE, CENTRAL) were searched using a combination of thesaurus and free text terms to identify studies comparing treatment outcomes of ruptured AAA in patients with hostile vs. friendly aortic anatomy. A systematic review was conducted that conformed to the PRISMA guidelines using a registered protocol (CRD42019127307). The primary outcomes were peri-operative mortality, freedom from aneurysm related mortality, and overall survival. Pooled estimates of dichotomous outcomes were calculated using odds ratio (OR) and 95% confidence interval (CI). A time to event data meta-analysis was conducted using the inverse variance method and the results were reported as summary hazard ratio (HR) and associated 95% CI. Subgroup analysis for type of treatment (endovascular aneurysm repair [EVAR] or open repair) was undertaken. Random effects models of meta-analysis were developed.

Results: Ten observational studies were included reporting a total of 1284 patients (748 with hostile anatomy and 536 with friendly anatomy). Patients with hostile anatomy had a higher peri-operative mortality than patients with friendly anatomy (OR 1.73, 95% CI 1.13-2.66; p = .01). Subgroup analysis showed a significant difference in peri-operative mortality in favour of friendly anatomy in patients treated by EVAR (OR 1.76, 95% CI 1.01-3.08; p = .05), but not in those treated by open repair (OR 1.37, 95% CI 0.83-2.27; p = .22). Patients with hostile anatomy treated by EVAR had a significantly higher hazard of death in follow up than patients with friendly aortic anatomy (HR 2.01, 95% CI 1.18-3.44, p = .01), whereas for open surgical repair, the survival was similar in patients with hostile and those with friendly aortic anatomy (HR 0.90, 95% CI 0.61-1.32, p = .58).

Conclusion: Hostile aortic anatomy is associated with increased mortality in patients with ruptured AAA treated by EVAR.

Keywords: Aortic aneurysm; Hostile anatomy; Instructions for use; Rupture.