Survival and Term-Outcomes of Open and Endovascular Surgical Repair of Unruptured Infrarenal Abdominal Aortic Aneurysms

W. S. C. Llalle, L, Cáceres-Farfán, M. Rojas-Huillca, M. Moreno-Loiza

Purpose: Endovascular aortic repair (EVAR) has become the standard management of unruptured infrarenal abdominal aortic aneurysm (UIAAA); however, current evidence is limited and uncertain when compared with open repair. Our study aimed to determine the survival and short- and long-term outcomes of EVAR versus an openprocedure in a Peruvian cohort of UIAAA.

Materials and Methods: This is a single-center observational, analytical, longitudinal study using a retrospective registry of 251 patients treated (205 EVAR vs 46 open procedures) for UIAAA from 2000 to 2017. Variables considered were baseline, comorbidities, clinical-surgical, type of treatment, short- (<30 days) and long-term (<5 years) outcomes, postoperative mortality according to the Vascular Quality Initiative (VQI) Risk Score, and survival curves, including reoperation-free rate and according to size (<65 mm vs >65 mm) of long-term UIAAA. All variables were grouped according to the treatment performed (EVAR vs open) and compared with descriptive, multivariate, Cox regression and Kaplan-Meier survival statistical analyses.

Results: The mean age was 74.5 years, and more than 50% of patients with UIAAA had diameters greater than 65 mm (P=.021). The calculated mortality rates (VQI) were 2.21% fpr versus 1.65% for EVAR. In short-term outcomes, mortality rates were 2.92% for open versus 0% for EVAR (P=.039), blood transfusion rates were 72.68% for open versus 17.39% for EVAR (P=.021), and overall hospital stays were 14 days for open versus 5 days for EVAR (P=.049). A 24% reduction in mortality (hazard ratio [HR], 0.76, 95% confidence interval [CI], 0.62–0.96; P=.045) and 19% reduction in readmission for aneurysmal rupture were identified for EVAR (HR, 0.81; 95% CI, 0.79–0.85; P=.031). In long-term outcomes, mortality rates were 3.41% for open versus 19.56% for EVAR (P=.047), aneurysmal rupture rates were 0% for open versus 13.04% for EVAR (P=.032), and reintervention rates were 2.43% for open versus 10.86% for EVAR (P=.002). An 86% risk of mortality (HR, 1.86, 95% CI, 1.32–2.38; P=.039) and 121% risk of readmission for aneurysmal rupture were identified for EVAR (HR, 2.21, 95% CI, 1.98–2.45; P=.028). At 5 years, survival rates were 93.67% for open versus 80.44% for EVAR (P=.043), and reintervention-free rates were 89.26% for open versus 47.82% for EVAR (P=.021). Also at 5 years, survival rates for treated IUAAAs smaller than 65 mm were 95.77% for open versus 63.63% for EVAR (P=.019) and for IUAAs larger than 65 mm were 92.53% for open versus 85.71% for EVAR (P=.059).

Conclusions: EVAR has shown better short-term benefit and survival rates than open management; however, the latter still prevails in the long-term in our Peruvian UIAAA cohort. Further follow-up studies are required to demonstrate the long-term benefit of EVAR in our population.