Large Diameter (≥29 mm) Proximal Aortic Necks Are Associated with Increased Complication Rates after Endovascular...

The aim of this study is to investigate the impact of proximal aortic diameter on outcome after endovascular aneurysm repair (EVAR) of infrarenal abdominal aortic aneurysms (AAAs).

This is a case-control (1:1) retrospective analysis of prospectively collected data on 732 AAA patients treated with EVAR in 2 university centers. Patients with an infrarenal neck diameter of 29-32 mm (wide neck, WN group) were compared with patients with a neck diameter of 26-28.9 mm (control group) matched for age, gender, and maximum aneurysmal sac diameter. Any patients treated outside the instructions for use of each endograft or with no adequate follow-up were excluded. The primary end point was any neck-related adverse event (a composite of type Ia endoleak, neck-related secondary intervention, and endograft migration) during follow-up.

Sixty-four patients with a proximal neck diameter of 29-32 mm (WN group) were compared with a matched control group of 64 patients with a neck diameter of 26-28.9 mm (control group). Oversizing was significantly higher in the study group (17.9% vs. 15.5%, P = 0.001). Overall median available follow-up was 24 months (range 12-84) (WN group 24 months vs. control group 18.5 months, P = 0.943). Primary end point was recorded in 8 patients (12.5%) of the WN group and in 1 patient (1.6%) of the control group. Freedom from the primary end point at 36 months (standard error <10%) was 87.3% for the study versus 98.4% for the control group (log rank = 4.66, P = 0.03). On multiple regression analysis, the presence of a proximal aortic neck >29 mm was the only independent risk factor for neck-related adverse events (odds ratio 7.4, 95% confidence interval 1.2-47.1).

EVAR in the presence of a wide proximal aortic neck is likely to be associated with higher adverse neck-related event rates and thus, in such cases closer follow-up may be required.