A significant proportion of current endovascular aortic aneurysm repair practice fails to meet Society for Vascular Surgery clinical practice guideline recommended abdominal aortic aneurysm diameter treatment thresholds in the Vascular Quality Initiative

Abstract

Background: There is mounting controversy surrounding the appropriate use of endovascular aortic aneurysm repair (EVAR) in contemporary practice. Persistent debate hinges on durability, cost, and survival. Accordingly, guidelines have attempted to clarify appropriate EVAR indications. The purpose of this analysis was to examine trends in EVAR practice throughout the United States and measure compliance with Society for Vascular Surgery (SVS) clinical practice diameter guidelines (CPGs).

Methods: We analyzed all elective repairs in the SVS Vascular Quality Initiative (VQI) EVAR registry from 2015 to 2019 (n = 25,112) and included patients with aneurysms confined to the infrarenal abdominal aorta. Center and surgeon variation with CPG diameter compliance was examined. Using a previously validated logistic regression model for risk adjustment, patients were stratified into predicted 1-year mortality risk tertiles and comparisons were made between patients meeting diameter guidelines (men ≥5.5;women ≥5.0 cm) and those who did not.

Results: Non-diameter-compliant EVAR occurred in 38.5% (n = 9675; diameter compliant, 61.5% [n = 15,437]). There was significant variation in CPG diameter compliance when stratified by VQI participating centers (range, 21%-95%; median, 61%; P < .001). This observation was amplified when categorized at the surgeon level (range, 0-100%; median, 63%; P < .0001). Notably, 82% of VQI surgeons (n = 852 of 1048) were non-diameter-compliant in more than 20% of their repairs. Moreover, among the 38.5% of patients failing to meet CPG diameter thresholds, 22.4% (n = 2171) were at high physiologic risk as determined by the validated SVS-VQI 1-year mortality calculator. Notably, the 1-year survival for the high-physiologic risk patients receiving non-guideline-compliant EVAR was worse compared with low- to intermediate-risk patients who were treated within recommended CPGs (92 ± 2% vs 97 ± 1%; log-rank P < .0001).

Conclusions: A significant percentage of current US EVAR practice fails to adhere to the SVS diameter guidelines, as highlighted by the tremendous variation among VQI centers and surgeons. Furthermore, as noted by the 22% of patients undergoing noncompliant repair deemed to be at high physiologic risk, patient selection for EVAR seems to be suboptimal. Surprisingly, these findings are observed among the majority of VQI surgeons performing EVAR. In light of issues surrounding durability and cost, efforts to constrain observed deviation from recommended therapeutic size threshold guidelines would likely serve to improve abdominal aortic aneurysm care throughout the United States.

Keywords: AAA; Aneurysm; Diameter; Outcomes; Practice guidelines.