The Correlation of Aortic Neck Length and Angle to Early and Late Outcomes in Endovascular Aneurysm Repair (EVAR) Patients

OBJECTIVES:
More liberal utilization of EVAR has been advocated. This study analyzes the correlation of aortic neck length and angle to early and late outcomes.

METHODS:
238 patients who underwent EVAR were followed clinically and had duplex ultrasounds and/or CTA every six months. Aortic neck length and angle were classified into ≥15 mm (L1, No.=195), ≥10-<15 mm (L2, No.=24), and <10 mm (L3, No.=17) and <45° angle (A1, No.=129), ≥45-<60° (A2, No.=43), and ≥60° (A3, No.=42). Univariate, multivariate analyses, and Kaplan-Meier methods were used to estimate freedom from late endoleak, early and late reintervention, and survival.
RESULTS:
The mean follow-up was 25 months (range: 1-87). The perioperative complication rates for Groups L1, L2, and L3 were similar, however they were 13%, 5% and 29% for Groups A1, A2, and A3, respectively (p=0.006). Proximal Type I early endoleaks occurred in 12%, 42%, and 53% in Group L1, L2, and L3; and 8%, 33%, and 38% in Group A1, A2, and A3, respectively (p<0.0001). Intraoperative proximal aortic cuffs were used in 10%, 38%, and 47% in L1, L2, and L3 groups; and in 7%, 28%, and 33% in A1, A2, and A3 groups, respectively (p<0.0001). Postoperatively, the size of the AAA decreased or remained unchanged in 95%, 94%, and 88% in L1, L2, and L3; and 96%, 94%, and 84% in A1, A2, and A3, respectively (p=0.0147). Freedom from late Type I endoleak rates at 1, 2, and 3 years were 84%, 82%, and 80% for L1, 68%, 54%, and 54% for L2, and 71%, 71%, and 53% for L3 (p=0.0263); 90%, 85%, and 85% for A1, 74%, 74%, and 68% for A2, and 64% 64%, and 53% for A3 (p=0.0013). Freedom from late intervention rates was similar for all groups.
CONCLUSIONS:
A short and angulated aortic neck was associated with a higher rate of early Type I endoleak, resulting in an increased use of proximal aortic cuffs.