Download Initial Experience with the Cordis Enterprise Stent

Applied Technologies for
Aneurysm Treatment
Rafael Rodriguez-Mercado, M.D.,F.A.C.S.
Acting Chancellor
Associate Professor Neurosurgery
Chief Endovascular Neurosurgery
Stroke Center Director ASEM
University of Puerto Rico
Medical Sciences Campus
Introduction

The endovascular approach has been gaining increasing
acceptance as an alternative treatment for both
ruptured and unruptured intracranial aneurysms (1).

Limitations to what types of aneurysms can be safely
and effectively treated.

Wide-necked (>4 mm or dome:neck ratio < 2) and fusiform
aneurysms without a well defined neck present a therapeutic
challenge because of the inability to ensure that the coils,
once deployed, will remain safely within the aneurysm and
not obstruct blood flow in the parent artery (2) .
1 International subarachnoid aneurysm trial (ISAT). Molyneux, Kerr, Yu,
Clarke, Sneade, Yarnold, and Sandercock. The Lancet, Vol 366. Sept 3, 2005. p
809-816.
2 Initial Clinical Experience with a New Self Expandng Nitinol Stent for the
Treatment of Intracranial Cerebral Aneurysms: The Cordis Enterprise Stent.
R. Higashida, V.Halbach, C. Dowd, L. Juravsky, and S. Meagher. American
Journal Neuroradiology (26): August, 2005. p 1751-1756.
History

Introduction of GDC coils in the early 1990’s :
 360° and 3-D coils, balloon remodeling and stent
assisted techniques, and liquid embolic agents.

2002: Neuroform® Stent (Boston Scientific)
approved in Europe and then FDA/ HDE
 Open cell design

2003: a safety and feasibility study to evaluate the
Enterprise® Stent was started in Europe (Germany and
Luxemburg; 30 pts, 31 aneurysms).
 Highly flexible nitinol stent, with closed cell design
Enterprise® Stent

Dec, 2006: Received CE mark in Europe for use with
occlusive devices in the tx of intracranial aneurysms.

May, 2007: Humanitarian Device Exemption (FDAHDE) granted for clinical use.
Closed Cell
Open Cell
Advantages
Closed
cell
design.
May be
partially
deployed
up to
70%.
Compatible with
standard
microcatheters..
Highly
flexible/
excellent
trackability.
Medications Recommended in Protocol
Pre-Procedure
– elective
• Aspirin: 325 mg qd 72 hours prior to procedure
• Clopidogrel: 75 mg qd 72 hours prior to procedure or a
loading dose of 300 mg given at least 6 hours prior to
procedure.
Pre-Procedure
– emergency
• Aspirin: 325 mg at the time of the catheterization prior
to procedure.
• Clopidogrel: A loading dose of 300 mg Clopidogrel given
at the time of catheterization prior to procedure.
IntraProcedure
• Weight adjusted bolus of IV heparin to maintain ACT
250-300 seconds throughout procedure.
• If GP IIB-IIIa Inhibitor given, maintain ACT < 220
seconds to minimize risk of bleeding.
PostProcedure
• Heparin drip is maintained for 24 after stent placement,
target PTT of 60-70 seconds.
• Aspirin:325 mg qd for at least one year
• Clopidogrel: 75 mg qd for at least 6 weeks
PR Subject Population

27 Subjects Enrolled
 2 Failed attempts due to tortuosity.

25 subjects received CORDIS Enterprise® Vascular
Reconstruction Device
 1 CORDIS Enterprise® Device per subject.

18 Subjects completed embolization
 7 Subjects pending embolization
Patient Demographics
Gender
N
%
Female
20
80
Male
5
20
Age
Years
Range
54
15-81
Mean
Patients and Methods

Aneurysm Location:
Carotid-ophthalmic segment: 15 (60%)
 Basilar tip: 2 (8%)
 Posterior Communicating: 1 (4%)
 Superior Hypophyseal: 1 (4%)
 Cavernous ICA: 1 (4%)
 ICA Posterior Wall: 2 (8%)
 ICA Bifurcation: 3 (12%)

Patients and Methods

Presenting Symptom:
 Incidental Finding: 17 (56%)
3/17 SAH from another aneurysm
 5/17 chronic HAs

Subarachnoid Hemorrhage: 6 (36%)
 Ipsilateral 3rd nerve palsy: 1 (4%)
 Loss of vision in ipsilateral eye: 1 (4%)


Aneurysm Dimensions:




Width: average 7.80mm
range 2.6-19.4mm
Height: average 6.60mm
range 2.1-22.4mm
*In recanalized aneurysms, measurement of filling portion
Parent vessel diameter: average 3.31mm range 1.5-4.8mm
Methods

Stent dimensions:



Enterprise stent 2.5 x 22mm: 23 (92%)
Enterprise stent 2.5 x 28mm: 2 (8%)
Note: indicated for vessels >2.5 mm in diameter.

All cases were performed under general endotracheal
anesthesia and via transfemoral approach.

Coiling was performed,



in same session in 3 cases (difficult anatomy and recent
SAH),
after 6 weeks (after endothelialization) in 15 cases,
and 7 cases are pending coiling.
Stent deployment
A 6 F Envoy® guiding catheter (Cordis
Neurovascular) was guided into either the
cervical internal carotid or vertebral
artery, depending on aneurysm location.
A 0.021” PROWLER® SELECT Plus
Infusion catheter, 5 cm distal length, is
navigated over a microguidewire at least 1
cm distal to aneurysm neck. Guidewire is
then removed.
Stent is introduced into the microcatheter
hub with an introducer sheath. The stent
is then pushed through the microcatheter
and placed across the aneurysm neck.
Stent deployment
If stent positioning is satisfactory, carefully
retract the infusion catheter, while maintaining
the position of the delivery wire.
As stent is deployed, up to 70% of the stent can
be opened up (approx. up to point until
proximal end of stent positioning marker is
aligned with distal marker band of infusion
catheter) , and stent verified by either direct
fluoroscopy or angiography.
If repositioning required, the stent can be
resheathed and the system either advanced
forward or pulled back for more accurate
placement. Coil aneurysm.
Angiographic Occlusion – Based on
the Modified Raymond Classification
Angiographic Outcome
Post-procedure
6-Months
n = 18
n = 10
Complete Obliteration
14(78%)
9 (90%)
Residual Neck
3(17%)
1(10%)
Residual Aneurysm
1 (5%)
0 (0%)
Complete
Residual Neck
Post procedure vs. 6-month result
Improved
Stable
Deteriorated
n = 10
0 (0%)
10 (100%)
0 (0%)
Residual
Aneurysm
Results

Successful stent placement: 25/27 cases (93%)

In 23 cases, stent was placed across aneurysm neck as
intended (92%).

Repositioning was required in one (4%) of the cases.

Length of follow up: Average 5.7 mos. Range 012.5 mos.
Results

No procedural morbidity or mortality.

No evidence of in-stent stenosis in available studies (DSA
and/or MRA).

In patients coiled in initial session (3):
 > 85% coil occlusion in immediate post op DSA

Patients coiled in a another session (15):
 > 80% coil occlusion in immediate post op DSA

No significant groin or retroperitoneal hematoma.
Recanalized Basilar Tip Aneurysm:
Stent Migration Case
Recanalized aneurysm
Delivery microcatheter in place
Stent migration, transverse position,
yet complete neck coverage
Recanalized Carotid Bifurcation
Aneurysm
Stent deployed and preparation for
coiling in another session
Completed Embolization
Posterior Wall ICA Aneurysm:
Jailing Technique Case
Stent Deployment
Coil Embolization
Postembolization runoff and
substracted views
Endovascular Neurosurgery
Research Group (ENRG)
Mocco J, Snyder KV, Albuquerque FC, Bendok
BR, Boulos AS, Carpenter JS, Fiorella DJ, Hoh
BL, Howington JU, Jankowitz BT, Liebman
KM, Rai AT, Rodriguez-Mercado R, Siddiqui
AH, Veznedaroglu E, Hopkins LN, Levy EI:
Treatment of Intracranial Aneurysms with
the Enterprise Stent: A Multicenter Registry.
Accepted for publication in J Neurosurg on July
24, 2008.
Conclusions





The use of the Enterprise® stent for treatment of
wide-necked aneurysms is feasible, safe and
effective.
A high resolution angiographic machine is necessary
for safe visualization of stent under fluoroscopy.
For stent deployment in areas of acute angulation,
longer sizes recommended to avoid migration.
Short term F/U has not shown in-stent stenosis or
thrombosis.
Larger sample size and long term F/U information
about stented aneurysm thrombosis and parent
vessel preservation are still necessary.
Endovascular Neurosurgery Research Group (ENRG) Members and Affiliations
Bernard Bendok, Northwestern University, Chicago, IL
Alan Boulos, State University of New York, Albany, NY
Richard D. Fessler, St. John Medical, Detroit, MI
Ricardo Hanel, Barrow Neurological Institute, Phoenix, AZ
L. Nelson Hopkins, State University of New York, Buffalo, NY
Jay Howington, Savannah Neurosurgery, Savannah, GA
Guiseppe Lanzino, University of Illinois, Peoria, IL
Elad I. Levy, State University of New York, Buffalo, NY
Demetrius K. Lopes, Rush-Presbyterian University, Chicago, IL
Robert Mericle, Vanderbilt University, Nashville, TN
Robert Replogle, Northern Rockies Neurosurgery, Billings, MT
Howard Riina, Cornell University, New York, NY
Andrew J. Ringer, University of Cincinnati, Cincinnati, OH
Rafael Rodriguez, University of Puerto Rico, San Juan, PR
Erol Veznedaroglu, Thomas Jefferson University, Philadelphia, PA
Thanks.
Rincón, PR