Standard endovascular aneurysm repair in patients with wide infrarenal aneurysm necks is associated with increased risk of adverse events.

Objective: Endovascular aneurysm repair (EVAR) has progressively expanded to treat more challenging anatomies. Although EVAR in patients with wide infrarenal necks has been reported with acceptable results, there is still controversy regarding the longer-term outcomes. Our aim is to determine the impact of infrarenal neck diameter on midterm outcome following EVAR with a single endograft with suprarenal fixation.

Methods: A retrospective case-control study was designed using data from a prospective multicenter database. Patients who electively underwent standard EVAR with an Endurant stent graft (Medtronic Ave, Santa Rosa, Calif) for a degenerative abdominal aortic aneurysm from January 2008 to December 2012 in three high-volume centers in The Netherlands were included. All measurements were obtained using dedicated reconstruction software and center-lumen line reconstruction. Patients with an infrarenal neck diameter of ≥30 mm were compared with patients with a neck diameter of <30 mm. The primary end point was freedom from neck-related adverse events (a composite of type Ia endoleak, neck-related secondary intervention, and endograft migration). Secondary end points were primary clinical success, type Ia endoleak, neck-related reinterventions, endoleaks, and aneurysm-related secondary interventions.

Results: Four-hundred twenty-seven patients were included. Seventy-four patients (17.3%) with a neck diameter of ≥30 mm were compared with a control group of 353 patients. There were no significant differences at baseline between groups including demographics, comorbidities, baseline aneurysm diameter, infrarenal neck length, suprarenal angulation, or infrarenal neck angulation. Median stent graft oversizing was 12.5% (7.9-16.1) and 16.6% (12.0-23.1) in the ≥30-mm neck-diameter and control groups, respectively (P < .001). Median follow-up was 3.1 years (1.2-4.7) and 4.1 years (2.7-5.6) for the large neck and control groups, respectively (P < .001). Type Ia endoleaks occurred in 17 patients (4.0%) and were significantly more frequent in patients with ≥30-mm neck diameter (9.5% vs 2.8%; P = .005). Neck-related secondary interventions were performed in 20 patients (4.7%) and were also more common among patients with neck diameters of ≥30 mm (9.5% vs 3.7%; P = .04). The 4-year freedom from neck-related adverse events were 75% and 95% for the large neck and control groups, respectively (P < .001). On multivariable regression analysis, infrarenal neck diameter of ≥30 mm was an independent risk factor for neck-related adverse events (odds ratio [OR], 3.8; 95% confidence interval [CI], 1.6-9.1), type Ia endoleak (OR, 2.7; 95% CI, 1.0-8.3), and neck-related secondary interventions (OR, 3.2, 95% CI, 1.1-9.2).

Conclusions: EVAR in patients with large diameter necks is associated with an increased risk of neck-related adverse events in midterm follow-up. This may influence the clinical decision regarding choice of repair and toward a more intensive surveillance following EVAR in these patients in the long term.