Changes in aortic dimensions and pulsatility following endovascular aneurysm repair using the Nellix endoprosthesis.

Abdominal aortic aneurysm (AAA) is a prevalent disorder affecting 4.3 to 8.8%
of men over the age of 60.1 Since the introduction of endovascular aneurysm
repair (EVAR) in the early 1990*s, EVAR is performed in the majority of
patients to prevent rupture. Endovascular Aortic replacement (EVAR) for the
treatment of aortic aneurysms is an established endovascular technique. In
spite of rigorous follow-up and improved stengraft desingn EVAR is still
associated with procedure related complications like type I and II endoleak. To
reduce the incidence of complications endograft development is ongoing. One of
the latest developments is the Nellix endoprosthesis. Unlike current devices
the Nellix endoprosthesis is composed of a stent-frame surrounded by endobags.
During placement these endobags are filled with a polymer. This polymer fills
up the original aneurysm sac, excluding the aneurysm and securing the
stent-frame within the aorta. Although promising the stresses and forces
exerted onto the endograft by aortic pulsatility may have an effect on the
durability and functioning of the endograft. By evaluating endograft movement
during the cardiac cycle (dynamic CTA) it is possible to assess the stress and
force exerted onto the Nellix device. This might help gain insight into
mechanisms underlying potential endograft failure, and aid the development of
future devices with long-term durability.

to quantitatively characterize the stresses and forces on an implanted
endograft during the cardiac cycle in terms of longitudinal movement.

Observational case series (pilot)

Regular preoperative and follow-up imaging for EVAR planning and follow-up
using the Nellix endoprosthesis consists of Computed Tomography Angiography
preoperative and at six weeks, six months and one year after EVAR. In this
study the preoperative and first follow-up CTA (6 weeks after EVAR) will be
replaced by a Dynamic CTA.