# Factors Affecting Post-EVAR Imaging Surveillance: An Opportunity for Improvement

## TL;DR

This study finds that patients living more than 50 miles away from the hospital are less likely to follow up for imaging after EVAR surgery, which is important for detecting complications like endoleaks.

## Contribution

The study identifies geographic distance as a novel risk factor for nonadherence to post-EVAR imaging guidelines.

## Key findings

- Adherence to EVAR imaging guidelines decreases by an average of 9.7% per year.
- Residence more than 50 miles from the institution is an independent risk factor for nonadherence (OR 1.76, p = 0.018).
- Type II endoleaks can be detected years after EVAR, even with declining adherence to imaging guidelines.

## Abstract

Background/Objectives: Appropriate imaging surveillance, established by the Society of Vascular Surgery (SVS), following endovascular aorta repair (EVAR) is critical for patient monitoring. We hypothesized that adherence to follow-up decreases over time, and therefore, the ability to detect endoleaks after EVAR also decreases. Methods: A retrospective cohort study of patients who underwent EVAR from 2014 to 2022 at our institution was completed. Patients were stratified by adherence to SVS guidelines for up to five years postoperatively. Demographics, detection of an endoleak > 30 days postoperatively, distance from our facility, and Area Deprivation Index (ADI) were collected. Comparisons of baseline comorbidities between groups and multivariate logistic regressions were performed using R studio. Results: 395 patients underwent an index EVAR at our institution from 2014–2022. 174 (44%) of patients adhered to all imaging recommendations, with an average loss to follow-up of 9.7% per year. 61 (15.4%) patients had a detected type II endoleak during the study period. Multivariable analysis identified residence > 50 miles from our institution as an independent risk factor for nonadherence (OR 1.76, p = 0.018) when controlling for age, sex, race, and ADI quartile. Conclusions: Adherence to surveillance guidelines gradually decreases after EVAR, but type II endoleak detection continues to occur years following the operation. While residence greater than 50 miles away was associated with nonadherence, patients’ ADI was not. Our results identify an opportunity for providers who may see patients more frequently to assist in reminding and arranging imaging follow-up for patients following their procedure.