Cardiovascular Journal of Africa: Vol 25 No 5 (September/October 2014)

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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 25, No 5, September/October 2014 AFRICA 239
Troubleshooting techniques for the Endurant™ device in
endovascular aortic aneurysm repair
George S Georgiadis, George A Antoniou, George Trellopoulos, Efstratios I Georgakarakos,
Christos Argyriou, Miltos K Lazarides
Abstract
Endovascular aortic aneurysm repair with the Endurant TM
stent-graft system has been shown to be safe and effective
in high-risk surgical patients with complex suprarenal and/
or infrarenal abdominal aortic aneurysm anatomy. The wire-
formed M-shaped stent architecture and proximal springs
with anchoring pins theoretically permit optimal sealing
in shorter and more angulated proximal aneurysm necks
even under off-label conditions. Nonetheless, extremely diffi-
cult anatomical situations and inherent graft system-related
limitations must be anticipated. Herein, we describe our
techniques to overcome the capture of the tip sleeve within
the suprarenal bare-stent anchoring pins, other endograft
segments, and native vessels.
Keywords: abdominal aortic aneurysm, endovascular aortic
aneurysm repair, stent-graft, Endurant device, techniques
Submitted 25/11/13, accepted 18/8/14
Cardiovasc J Afr 2013; 24: 239–243
DOI: 10.5830/CVJA-2014-049
Previous randomised trials have confirmed the short and
mid-term benefits of endovascular abdominal aortic aneurysm
repair versus open repair.1,2 However, its success is dependent
on specific anatomical parameters that include the abdominal
aortic aneurysm (AAA) morphology and dimensions. Adverse
anatomical characteristics such as very short and severely
angulated proximal aortic necks or small and tortuous iliac
arteries can occasionally preclude its use. Advances in AAA
endograft device technology have significantly contributed to
improved patient outcomes, and durability of the procedure
allows for a wider therapeutic spectrum of patients to receive
endovascular repair (EVAR).
The success of these new stent-graft devices results from
better adaptation and improved performances in challenging
anatomies and better trackability of delivery systems.3-8 Specific
advancements include improved tip design and greater flexibility,
controlled proximal stent-graft release mechanism with
re-positional proximal stent-graft capabilities, and improved
deliverability and placement accuracy.3-9 These technological
advances, combined with cumulative physician clinical experience
and enhanced skill sets, have resulted in the consideration of
endoluminal grafting in off-label conditions.
A recent report highlighted the application of troubleshooting
techniques to overcome ‘pitfalls’ in some of the steps of EVAR
with the Endurant™ (Medtronic Cardiovascular, Santa Rosa,
CA) stent-graft device.10 Herein, we specifically describe simple
techniques to overcome capture of the EndurantTM tip sleeve
within the suprarenal bare-stent anchoring pins or within
other endograft and native vessel segments, in order to avoid
emergency conversion to open repair and the potential for
adverse outcomes.
The Endurant TM stent-graft system
This stent-graft is a new fourth-generation device comprising
a high-density multifilament polyester graft material of low
porosity, externally supported by an electropolished nitinol stent
structure and loaded in a low-profile hydrophilic coating delivery
system. The seals of the European Union (EU) as well as Food
and Drug Administration (FDA) approval for this device were
received in July 2008 and December 2010, respectively.
The EndurantTM stent-graft is designed to enhance
performance in AAA patients with straightforward (friendly)
or challenging (hostile) anatomies. Its high flexibility and
conformability enables the device to adapt to straight as well
as severely tortuous proximal aortic necks and challenging iliac
artery anatomies. These stent-grafts have a sinusoidal M-shaped
architecture with a small amplitude providing optimal sealing
in short and angulated proximal aneurysm necks. Furthermore,
the M-shaped proximal stent at the upper pole of the endograft
body facilitates enhanced wall apposition, minimising the risk of
in-folding and providing another 5 mm of sealing zone.
The EndurantTM stent-graft relies on proximal active fixation,
incorporating a suprarenal bare stent ring with anchoring pins
of increased flexibility, compared to earlier generation stent-
grafts. Initially covered by the tip sleeve, the suprarenal stent with
anchoring pins provides controlled release and secure fixation. The
radiopaque markers at the proximal and distal edges of the stent-
graft as well as the flow divider and contralateral gate markers
ensure accurate positioning of the device. Apart from a more
flexible main body, the limb stent and optimal stent spacing offer
Department of Vascular Surgery, Demokritus University
of Thace, University General Hospital of Alexandroupolis,
Greece
George S Georgiadis, MD, PhD,
Efstratios I Georgakarakos, MD, PhD
Christos Argyriou, MD
Miltos K Lazarides, MD, PhD, EBQSvasc
Department of Vascular Surgery, Red Cross Hospital of
Athens, Greece
George A Antoniou, MD, PhD
Surgical Sector, Vascular Surgery Unit, Georgios
Papanikolaou Hospital, Thessaloniki, Greece
George Trellopoulos, MD