Outcomes of the Repair of 1000 Abdominal Aortic Aneurysms in the Endovascular Era.

Background: To analyze the outcome of abdominal aortic aneurysm (AAA) repair with elective open surgery (OS) versus endovascular aneurysm repair (EVAR) and assess the predictors of survival.

Methods: A retrospective cohort study was made of 1000 AAA treated between January 1998 and November 2014 (68.1% OS and 31.9% EVAR), with the comparison of comorbidity and complications, and survival analysis (Kaplan-Meier and Breslow). Multivariate logistic regression and Cox regression analyses were performed.

Results: The EVAR group had a higher prevalence of smokers (33.2% vs. 21%; P < 0.001), hypercholesterolemia (56.4% vs. 41.1%; P < 0.001), type 1 diabetes (11.3% vs. 2.8%; P < 0.001), ischemic heart disease (36.4% vs. 25.0%; P = 0.013), chronic renal failure (25.4% vs. 16.2%; P < 0.001), and an older age [74.6 ± 7.1 vs. 68.3 ± 7.2 (years); P < 0.001]. The OS group showed a greater prevalence of chronic ischemia of the lower extremities (22.8% vs. 9.4%; P < 0.001), a greater AAA diameter [61.2 ± 13.6 vs. 58.5 ± 13.8 (mm); P < 0.001], a greater aneurysm neck diameter [24.1 ± 3.9 vs. 23.3 ± 3.0 (mm); P = 0.002], and a shorter aneurysm neck length [15.1 ± 11.1 vs. 24.0 ± 11.1 (mm); P < 0.001]. Early mortality was low in both groups but higher with OS (1.9% vs. 0.3%; P = 0.046). OS [OR 16.98 (95% CI: 1.97-146.29) (P < 0.001)] and age [OR 1.22 (95% CI: 1.09-1.36) (P < 0.001)] were independent predictors of higher early mortality. However, there was no increase in mortality in the OS group in patients under 73.5 years (P = 0.996), and the differences increased over 73.5 years of age (P = 0.005). There were also more postoperative complications (23.9% vs. 9.7%; P < 0.001) and early reinterventions in the OS group (4.4% vs. 1.6%; P = 0.026). Only the prevalence of renal function impairment was greater in the EVAR group (6.6% vs. 3.5%; P = 0.034), but this complication resulted not significative in the multivariate analysis [OR 0.84 (95% CI: 0.41-1.69) (P = 0.618)]. The median duration of follow-up was 33 (range 0-175) and 59 months (range 0-190) for the EVAR and OS groups, respectively. The survival rate after 24 and 48 months was 92.9% and 83.9% (EVAR) versus 94.6% and 90.6% (OS) (P < 0.001). This difference was not significative in the multivariable analysis: hazard ratio (HR) 1.46 (95% CI 0.99 to 2.12); P = 0.060. OS also resulted in better freedom from reintervention rates for the same periods: 92.1% and 90.4% versus 92.9% and 88.1%, including multivariate analysis [HR 1.93 (95% CI 1.27 to 2.93) P = 0.002]. The factors independently associated to poorer survival were age [HR 1.09 (1.06-1.11); P < 0.001], chronic obstructive pulmonary disease [HR 1.39 (1.04-1.86); P = 0.026], and chronic renal failure [HR 2.08 (1.51-2.87); P < 0.001].

Conclusions: Elective AAA repair offers excellent middle-term outcomes with both OS and EVAR. EVAR reduces early mortality in the subgroup of patients older than 73.5 years. In patients younger than 73.5 years with a low to moderate surgical risk, EVAR offers no advantage over OS and therefore should not be regarded as the treatment of choice.