To compare the clinical efficacy of endovascular aortic aneurysm repair (EVAR) and open surgery repair (OSR) in the treatment of complex abdominal aortic aneurysm (cAAA).

The clinical data of 144 patients with cAAA were retrospectively analyzed. All patients were diagnosed and treated in Beijing Anzhen Hospital Affiliated to the Capital Medical University, The First Medical Center of Chinese PLA General Hospital, Beijing Hospital, and Xuanwu Hospital of Capital Medical University from June 2016 to December 2021. They were divided into EVAR group (n=114) and OSR group (n=30) according to different treatments. The preoperative clinical characteristics, operation, and follow-up results of the two groups were compared. Subgroup analysis was performed in the EVAR group according to different treatments. Two independent samples t-test was used for inter-group comparison of measurement data follow the normal distribution, rank-sum test was used for non-normal data, and Chi-square test or Fisher's exact probability test was used for count data.

In EVAR group, the diameter of proximal aneurysm neck was wider than in OSR group, and the proportion of trapezoidal neck was higher than in OSR group, and the differences were statistically significant [(22.03±3.59) mm vs (19.40±4.28) mm, P=0.002; 36.0% vs 16.7%, P=0.044). The operation time, intraoperative bleeding volume, and perioperative blood transfusion volume in EVAR group were lower than those in OSR group. There were statistically significant differences [(158.56±93.06) min vs (368.53±95.96) min, t=-10.915, P<0.001;(92.84±168.83)ml vs (1 370.00±1 019.52) ml, t=-12.579, P<0.001; (14.91±133.85) ml vs (1 375.00±1 300.18)ml, t=-11.055, P<0.001). 144 patients were followed up for (25.6± 10.4) months. The total complication rate and perioperative complication rate in EVAR group were lower than in OSR group. The differences had statistical significance(16.7% vs 40.0%, χ²=7.654, P=0.006; 9.6% vs 40.0%, χ²=16.301, P<0.001).There was no statistically significant difference in the quality of life scores between the two groups at 1-year follow-up. Subgroup analysis showed that the endoleak rate in the conventional EVAR group was significantly higher than that in the unconventional EVAR group (11.9% vs 0%, χ²=6.035, P=0.014). When cervical angle ≥52°, the complication rate of conventional EVAR was significantly higher than that of patients with narrower angle (29.6% vs 0%, χ²=6.486, P=0.011). In the treatment of patients with trapezoidal neck, conventional EVAR group had a higher endoleak rate than unconventional EVAR group (19.0% vs 0%, χ²=6.632, P=0.010). The incidence of complications in OSR group was correlated with concomitant diseases, and the proportion of patients with complications complicated with coronary heart disease and cerebrovascular disease was significantly higher than that of patients without complications (75% vs. 27.8%, χ²=6.451, P=0.011; 25% vs. 0%, χ²=5.000, P=0.025).

In the treatment of patients with cAAA, the total complication rate of EVAR, especially the perioperative complication rate, is lower than that of OSR. Choosing appropriate patients and correct treatment may reduce the risk of postoperative complications and endoleak of EVAR.

Abdominal aortic aneurysm; Endovascular aortic aneurysm repair; Open surgery repair; Multicenter study; Chimney technique; Fenestration technique