Objective: This study quantifies the survival and outcomes associated with endovascular aneurysm repair (EVAR) patients treated in two eras. We hypothesized that both end points will improve over time.
Methods: Patients receiving EVAR between January 2003 and May 2017 contained within the Vascular Quality Initiative data set were examined. Those patients treated between January 2003 and December 2007 were included in the early era, and those treated between January 2012 and December 2015 were considered late era. Baseline demographics, technical variables, and outcomes were compared with appropriate statistical tests. Survival was estimated with Kaplan-Meier life-table analysis. Cox proportional hazards modeling analyzed the relationship between repair era and survival; the repair era's significance was further examined in matched cohorts generated by coarsened exact matching and propensity scoring.
Results: Early era (n = 787) patients demonstrate decreased estimated survival in comparison to those treated in the late era (n = 20,066; log-rank, P < .001). Repair in the late era was not an independent predictor of survival in the Cox model (hazard ratio, 1.06; 95% confidence interval, 0.23-4.95; P = .94). Three different matching methods confirmed a nonsignificant contribution of treatment era to survival suggested by the initial Cox model (all P > .05). Total hospital stays were longer in the late era (3.1 vs 4.2 days; P < .001). Postoperative myocardial infarction and surgical site infections decreased in frequency in the late group, although postoperative vasopressor use became more frequent (all P < .05). Operations became 20% faster, required 27% less contrast material and 29% less crystalloid, and lost 30% less blood over time (all P < .05).
Conclusions: Although EVAR volume increased significantly over time, post-EVAR outcomes of patients do not differ between the early era, 2003 to 2007, and the late era, 2012 to 2015. Aspects of surgical performance improved, but this did not translate into a measurable benefit to patients. Length of hospital stay unexpectedly increased over time.
Keywords: Abdominal aortic aneurysm; Health services research.
Copyright © 2018 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.