Understanding who benefits from endovascular aortic repair in those deemed unfit for open repair.

Introduction: Patients with abdominal aortic aneurysms (AAAs) who are deemed unacceptable candidates for open repair (UNFIT) pose a clinical challenge. The EVAR2 Trial randomized UNFIT patients to endovascular aortic repair (EVAR) vs no intervention from 1999 to 2003, concluding that survival was not improved by EVAR. However, outcomes after EVAR over the last 2 decades have dramatically changed. Thus, the purpose of this study was to evaluate outcomes after EVAR in UNFIT patients using more contemporary data and to determine which subsets of UNFIT patients may potentially benefit from EVAR.

Methods: The Vascular Quality Initiative database (2003-2020) was used to identify elective EVARs for AAAs. Patients were categorized as UNFIT or suitable (SUITABLE) for open repair by the operative surgeon. Predicted 1-year mortality of untreated AAAs was calculated via a modified Gagne Index adjusted for AAA size. The primary outcome for the study was 30-day mortality. Secondary outcomes included perioperative major adverse cardiac events (a composite of clinically significant arrhythmia, congestive heart failure, and myocardial infarction), length of stay, and 1-year mortality.

Results: A total of 31,471 patients met study criteria with 27,036 (85.9%) deemed SUITABLE and 4435 (14.1%) UNFIT. UNFIT patients were more likely to experience a perioperative major adverse cardiac event (5.1% vs 2.2%, P < .001) and had longer lengths of stay (1 day [interquartile range, 1-3 days] vs 1 day [interquartile range, 1-2 days], P < .001). The 30-day mortality was significantly higher for UNFIT patients (0.8% vs 0.4%, P < .001). UNFIT patients had worse 1-year survival compared with SUITABLE patients. However, UNFIT and SUITABLE patients had significantly improved actual 1-year mortality with EVAR compared with predicted 1-year mortality without EVAR: 9.5% vs 15.6% (P < .001) and 4.0% vs 11.7% (P < .001), respectively. The mortality benefit after EVAR in UNFIT patients was primarily restricted to those with smaller Gagne Indices and larger aneurysm diameters. Patients deemed unsuitable for open repair due to frailty or multiple reasons had significantly higher 30-day mortality rates after EVAR when compared with SUITABLE patients (1.3% vs 1.6% vs 0.4%, P < .001). Those deemed unsuitable for open repair due to frailty or multiple reasons had worse 1-year cumulative survival compared with all other UNFIT patients.

Conclusions: Despite being high risk with higher perioperative morbidity and mortality, UNFIT patients have lower actual 1-year mortality with EVAR than predicted 1-year mortality without EVAR. However, this potential benefit is reserved to those with small Gagne Indices, larger AAA diameters, and lack of frailty.