Understanding the Risks of Abdominal Aortic Endograft Explantation with Early Outcomes from Two Decades of Experience.

Abstract

Objectives: Endovascular aneurysm repair (EVAR) currently comprises more than two thirds of all AAA repairs in the United States. However, data show that patients are at higher risk for late mortality after EVAR compared to open repair. As the number of aging EVARs grow, so, too, does the number requiring explant. The objective of this work is to highlight perioperative details and outcomes of EVAR explantation to allow physicians to better counsel patients regarding the perioperative risks.

Methods: We abstracted all open aortic procedures performed at the University of Michigan from January of 2002 to January of 2024, from which cases of late aortic endograft explants (>30 days) were identified. We then collected and compared data regarding pre-operative demographics & aneurysm related history, peri-operative characteristics, and post-operative course including explant indication and endograft type using t-test, χ2, or their non-parametric counterpart when appropriate. Multivariable logistic regression models were developed to evaluate postoperative complications and 30-day mortality rates. Survival was compared using Kaplan-Meier survival analysis.

Results: 142 EVAR explants were evaluated, 100 for endoleak and 42 for infection from 2002-2024. Patients with infected endografts were more likely than those with endoleaks to have any complications (57.1% vs 32.0%, p=0.006) and serious complications (54.8% vs 30.0%, p=0.005). Real world complications were reflected in NSQIP estimated risks, with infected endograft patients at a higher predicted NSQIP risk than endoleak patients for any complication (44.9% vs 35.6%, p<0.001), serious complication (35.7% vs 29.2%, p <0.001), and 30-day mortality (19.0% vs 7.0%, p=0.03). No differences were seen based on endograft type. Infected endografts were at higher risk for mortality at 30 days (28.6% vs 14.0%, p=0.03). That trend persisted to 2 years (38.1% vs 15.0%, p=0.007). Most mortality occurred by post-op day 45.

Conclusions: EVAR explantation regardless of indication places patients at high risk for mortality, with infection conferring early mortality risk in this cohort. This work underscores the need for a candid discussion regarding operative risk with patients facing explantation.