Noncylindrical neck anatomy
An international team of investigators analyzed the incidence and impact of noncylindrical neck anatomy, defined as a 2-mm or greater change in diameter over the first 15 mm of proximal aortic neck length. Of 3,077 GREAT participants treated with the Gore Excluder endograft, 1,312, or 43%, had an hourglass, tapered, or conical neck shape that qualified as noncylindrical. Noncylindrical necks were more common in women. Fifteen percent of patients with a noncylindrical neck received the device outside the Excluder IFU, as did 11% with a cylindrical neck.
After an average follow-up of about 20 months, the noncylindrical neck group had a 3.1% rate of device-related intervention, significantly better than the 4.9% rate in patients with a cylindrical neck. In a multivariate regression analysis, female gender and maximum abdominal aortic aneurysm diameter were significant risk factors for device-related or endoleak-specific reintervention; noncylindrical neck morphology was not. Indeed, women were 2.2-fold more likely to require device-related reintervention than men (J Vasc Surg. 2018; 68[6]:1714-24).
Large proximal aortic neck
Of 3,166 consecutive patients in GREAT, 37.6% had a large aortic neck diameter, defined as 25 mm or wider. The rate of 5-year freedom from type Ia endoleak was 96.8% in the large-neck group, significantly less than the 98.6% rate in patients with a normal aortic neck diameter. Of note, rates didn’t diverge until after 2 years of follow-up, emphasizing the need for careful long-term surveillance despite initial technical success.
The 5-year rate of freedom from the primary composite endpoint of type Ia endoleak, reintervention, aortic rupture, or isolated aortic-related mortality was also significantly worse in the large-neck group: 81.3% versus 87%. Moreover, the 5-year survival rate was only 64.6% in the large–aortic neck group, compared with 76.5% in the comparator arm, even though aortic-related mortality didn’t differ between the two groups. “The findings raise the question of whether young patients, with predicted life expectancies exceeding 10 years, should receive standard endovascular intervention if they have large aortic neck diameters at baseline (Eur J Vasc Endovasc Surg. 2018;56[2]:189-99).