The association of ruptured abdominal aortic aneurysm diameter with mortality in the International Consortium of Vascular Registries

Abstract

Background: The mortality after ruptured abdominal aortic aneurysm (rAAA) repair is high, despite improvements in perioperative care, centralization of emergency vascular surgical services, and the introduction of endovascular aneurysm repair (EVAR). The diameter of intact AAA has been shown to be a predictor of short- and long-term survival. The aim of this study was to analyze the impact of AAA diameter on mortality for rAAA repair using contemporary data collected from the International Consortium of Vascular Registries and compare outcomes by sex and the type of repair patients received.

Methods: Prospective registry data on repair of rAAA from seven countries were collected from 2010 to 2016. The primary outcome was perioperative mortality after EVAR and open surgical repair (OSR). Data were stratified by type of repair and sex. Logistic regression models were used to estimate odds ratio (OR) for the association between AAA diameter and perioperative mortality and the association between type of repair and mortality. Multivariable logistic regression models were used to adjust for differences in patient characteristics.

Results: The study population consisted of 6428 patients with a mean age ranging from 70.2 to 75.4 years; the mean AAA diameter was 7.7 ± 1.8 cm. Females had a significantly smaller AAA diameter at presentation compared with males (6.9 ± 1.6 cm vs 7.9 ± 1.8 cm; P < .001). who underwent OSR had larger AAA diameters compared with those who underwent EVAR (P < .001). Females who underwent repair were significantly older (P < .001). Males were more likely to have cardiac disease, diabetes mellitus, and renal impairment. Overall, AAA diameter was a predictor of mortality in univariate and multivariate analysis. When analyzing EVAR and OSR separately, the impact of AAA diameter per cm increase on mortality was apparent in both males and females undergoing EVAR, but not OSR (EVAR: male OR, 1.09 [95% confidence interval, 1.03-1.16] and EVAR: female OR, 1.17 [95% confidence interval, 1.02-1.35]). The early mortality rate for males and females who underwent EVAR was 18.9% and 25.9% (P < .001), respectively. The corresponding mortality for males and females who underwent OSR was 30.2% and 38.6% (P < .001), respectively.

Conclusions: In these real-world international data, there is a significant association between rAAA diameters and early mortality in males and females. This association was more evident in patients undergoing EVAR, but not shown in OSR. Despite improvements in overall AAA repair outcomes, the risk of mortality after rAAA repair is consistently higher for females.

Keywords: Abdominal aortic aneurysm; EVAR; Mortality; Registry; Surgery.