ObjectiveEndovascular abdominal aortic aneurysm repair (EVAR) has been preferred to open surgical repair (OSR) for the treatment of abdominal aortic aneurysms (AAAs) in high-risk patients. We compared the perioperative and long-term outcomes of EVAR for patients designated as unfit for OSR using a large national dataset. MethodsThe Vascular Quality Initiative database was queried for patients who had undergone elective EVAR for AAAs >5 cm from 2013 to 2019. The patients were stratified into two cohorts according to their suitability for OSR (fit vs unfit). The primary outcomes included perioperative (in-hospital) major adverse events, perioperative mortality, and mortality at 1 and 5 years. Patient demographics and postoperative outcomes were analyzed to identify the predictors of perioperative and long-term mortality. ResultsOf 16,183 EVARs, 1782 patients had been deemed unfit for OSR. The unfit cohort was more likely to be older and female, with a greater proportion of hypertension, coronary artery disease, congestive heart failure, chronic obstructive pulmonary disease, and larger aneurysm diameters. Postoperatively, the unfit cohort was more likely to have experienced cardiopulmonary complications (6.5% vs 3%; P < .001), with greater perioperative mortality (1.7% vs 0.6%; P < .001) and 1- and 5-year mortality (13% and 29% for the unfit vs 5% and 14% for the fit cohorts, respectively; P < .001). A subgroup analysis of the unfit cohort revealed that those deemed unfit because of a hostile abdomen had significantly lower 1- and 5-year mortality (6% and 20%, respectively) compared with those considered unfit because of cardiopulmonary compromise and frailty (14% and 30%, respectively; P = .451). Reintervention-free survival at 1 and 5 years was significantly greater in the fit cohort (93% and 82%, respectively) compared with that for the unfit cohort (85% and 68%, respectively; P < .001). The designation as unfit for OSR was an independent predictor of both perioperative (odds ratio, 1.59; 95% confidence interval [CI], 1.03-2.46; P = .038) and long-term mortality (hazard ratio [HR], 1.92; 95% CI, 1.69-2.17; P < .001). Advanced age (odds ratio, 2.91; 95% CI, 1.28-6.66; P = .011) was the strongest determinant of perioperative mortality, and end-stage renal disease (HR, 2.51; 95% CI, 1.78-3.55; P < .001) was the strongest predictor of long-term mortality. Statin use (HR, 0.77; 95% CI, 0.69-0.87; P < .001) and angiotensin-converting enzyme inhibitor use (HR, 0.83; 95% CI, 0.75-0.93; P < .001) were protective of long-term mortality. ConclusionsDespite low perioperative mortality, the long-term mortality of those designated by operating surgeons as unfit for OSR was rather high for patients undergoing elective EVAR, likely owing to the competing risk of death from medical frailty. An unfit designation because of a hostile abdomen did not confer any additional risks after EVAR. Judicious estimation of the patient's life expectancy is essential when considering the treatment options for this subset of patients deemed unfit for OSR.