Predictors of Early Mortality After Open Aorto-Iliac Reconstruction in Patients with Aortoiliac Occlusive Disease: An Observational Cohort Study

Abstract

Background and Objectives: Open aorto-iliac reconstruction (AIR) for aorto-iliac occlusive disease (AIOD) remains a high-risk procedure due to multifocal atherosclerosis affecting coronary, cerebrovascular, and renal arterial beds. This study aimed to identify factors independently associated with 30-day mortality and explore factors associated with late mortality during available follow-up among 30-day survivors following open AIR. Materials and Methods: An observational, non-randomised cohort of 170 consecutive patients undergoing open AIR for AIOD between January 2018 and December 2024 was analysed. Univariate logistic regression was performed for 30-day mortality; given the limited number of events (n = 16), the primary multivariable analysis used penalized likelihood logistic regression (Firth correction). Late survival among 30-day survivors (landmark cohort, n = 154) was analysed using Kaplan–Meier methods and exploratory univariate Cox proportional hazards regression, with surviving patients censored at the last available follow-up; multivariable Cox modelling was not performed due to the limited number of late events (n = 10). Results: Thirty-day mortality was 9.4% (16/170) in the overall cohort. In the primary Firth penalized multivariable logistic regression, factors associated with 30-day mortality were: severe left IIA stenosis ≥ 70% (OR 9.68; 95% CI 3.08–30.43; p = 0.0001), chronic kidney disease (OR 3.62; 95% CI 1.03–12.66; p = 0.044), and increasing aortic cross-clamp duration, analysed continuously (OR 1.022 per minute; 95% CI 1.000–1.045); a conventional ≥60 min categorical threshold showed a consistent secondary association (OR 4.15; 95% CI 1.28–13.46; p = 0.018). Non-inclusion of IIA was associated with increased 30-day mortality on univariate analysis (OR 4.80; 95% CI 1.31–17.62; p = 0.018). Among the 154 patients entering the 30-day landmark cohort, 10 late deaths were observed during available follow-up. In exploratory univariate Cox regression, intraoperative blood loss was the only statistically significant factor associated with late mortality (HR 1.07 per 100 mL; 95% CI 1.03–1.12; p = 0.0006). Conclusions: Severe IIA disease, chronic kidney disease, and increasing aortic cross-clamp duration (analysed continuously) were independently associated with increased 30-day mortality after open AIR. Intraoperative blood loss was associated with late mortality in exploratory univariate survival analysis. These findings require validation in larger prospective cohorts with longer and more uniform follow-up.