Covered Stents:
Best Patient Candidates…
and Where to Avoid
Barry S. Weinstock, MD
Mid-Florida Cardiology Specialists
Orlando, FL
Director, Mid-Florida Cardiology
Vascular Intervention Center

Covered Stents
“Covered stent” virtually synonymous with “Gore
Viabahn”, particularly for use in SFA but also in iliac
Other covered stents available for use in the U.S.
Atrium iCast – balloon expandable so appropriate
for use in iliac but not in SFA
Bard Fluency self-expanding stent (off-label
vascular use)

What’s so great about the SFA?
SFA disease typically does NOT cause critical limb
ischemia
Even patients with CTO’s  claudication, not CLI
CLI may be due to isolated tibial disease but often is due
to multi-level disease
Key to wound healing / limb salvage is “straight-line” flow
to the foot … not starting at the knee!
Challenging vessel: Frequent severe Ca2+, frequent CTO,
under-appreciated tortuosity / flexion / fore-shortening /
compression

Highly Calcific Distal SFA CTO
90 yr old male
Critical Limb Ischemia:
Non-healing right toe
ulcer
SFA CTO, severe
trifurcation vessel disease
HTN, Dyslipidemia
Hx CABG

SFA hostile for most stents
Knee Extension Knee Flexion

Viabahn Endograft Overview
Approved in June 2005,
the GORE VIABAHN®
Endoprosthesis is the only
stent-graft available in the
US with an SFA
indication.
Indicated for improving
blood flow in patients with
symptomatic peripheral
arterial disease in
superficial femoral artery
lesions with reference
vessel diameters ranging
from 4.0 mm – 7.5 mm.

Viabahn Characteristics
Polished nitinol support
Ultra-thin wall ePTFE
tube
Unique, durable bonding
film
Heparin Bioactive
Surface
Lengths: 2.5, 5, 10, and
15 cm
Diameters: 5 – 8 mm

Compliant with the
Mechanical Forces of the SFA
• Over 70,000 GORE VIABAHN®
Endoprosthesis sold worldwide
• No fractures reported in the SFA
• Capable of longitudinal
compression with little residual
force
• Superb flexibility

Mechanical Forces in the SFA
The GORE VIABAHN® Endoprosthesis is
capable of longitudinal compression with little residual force
• Longitudinal Compression
• “From the supine position to the fetal position, the SFA
shortened 13% ± 11% (P < .001)” 1
1 Cheng CP, Wilson NW, Hallett RL, Herfkens RJ, Taylor CA. In Vivo MR Angiographic Quantification of
axial and twisting deformations of the superficial femoral artery resulting from maximum hip and knee
flexion. Journal of Vascular & Interventional Radiology 2006;17(6):979-987.

Mechanical Forces in the SFA
• Flexion
• “The curvature of the femoral vessels was studied
and quantified in stretched and flexed
positions…Three or more small curves were seen
proximal to the knee joint in all volunteers”1
• Outstanding bending and flexibility
• Durability
• “One premise is that the SFA … undergo[es] unique
and severe conformational changes that can literally
pull apart a metal device (stent).”2
• No fractures reported worldwide in the
SFA
1 Wensing PJ, Scholten FG, Buijs PC, Hartkamp MJ, Mali WP, Hillen B. Arterial tortuosity in the femoropopliteal region during knee
flexion: a magnetic resonance angiographic study. Journal of Anatomy 1995;187(Pt 1):133-139.
2 Smouse HB, Nikanorov A, LaFlash D. Biomechanical forces in the femoropopliteal arterial segment. What happens during extremity
movement and what is the effect on stenting? Endovascular Today 2005;4(6):60-66.

Indications for Viabahn in the SFA
• TASC C or D Lesions, some TASC B Lesions
• Long lesions, esp. CTO’s
• Severe calcific (diffuse) disease… but prefer “vessel
prep” pre-Viabahn
• ev3 “RockHawk” or CSI “DiamondBack” to change
vessel compliance and promote full stent expansion
• Perforations / Aneurysms / Pseudo-aneurysms
• Off-label treatment of nitinol stent restenosis

Keys to Viabahn Stent Success
• Larger vessels > 5 mm diameter have better patency
rates than smaller vessels
• Viabahn stent should be over-sized by 1.0 mm
compared to estimated vessel size
• Avoid placing 5 mm Viabahn stents when possible
• Avoid SFA Viabahn stents in patients without at least
one patent trifurcation vessel that is free of significant
stenosis
• Treat BTK vessel(s) if necessary to ensure adequate distal
run-off

Keys to Viabahn Stent Success
• Avoid Viabahn stents in patients who are unlikely to be
compliant with long-term dual anti-platelet therapy
• Stent from “normal to normal” and stent proximal lesions
back to ostium
• Avoid dilating pre- or post-Viabahn outside borders of
stent to avoid edge dissections  restenosis
• Post-dilate at high pressure with balloon matching stent
diameter

R.M. -- Long SFA Flush Ostial CTO
• 76 yr old male; severe
bilateral claudication
• Inoperable CAD; Severe
COPD; Long-Standing
IDDM; Chronic renal
insufficiency
• Bilateral SFA CTO’s
• Left SFA Flush ostial
occlusion, no visible
stump of SFA

R.M. – LSFA flush ostial CTO
•CTO crossed with QuickCross
and Glide Wire
•Atherectomy with SilverHawk
LX-M
•PTA of entire SFA 6x100 mm
•Viabahn Stents x 3
•7x15 cm, 7x15 cm, 7x5 cm
•Stents post-dilated at high
pressure with 7x10 cm PTA
•F/U Doppler: ABI 1.06 with
widely patent stents

Patency of VIABAHN® in the SFA
(708 Limbs, 14 Independent Studies)

VIABAHN® SFA Primary Patency
(708 Limbs, 14 Independent Studies)

One-Year Primary Patency Based
on Lesion Length
(625 Limbs, 13 Independent Studies)*
*Coats et al. did not report lesion length.

Randomized comparison of percutaneous Viabahn
vs. prosthetic femoral-popliteal bypass in the
treatment of SFA occlusive disease
Kedora J, Hohmann S, Garrett W, Munschaur C, Theune B, Gable D. Randomized comparison of
percutaneous Viabahn Stent-Grafts versus prosthetic femoral-popliteal bypass in the treatment of
superficial femoral arterial occlusive disease. Journal of Vascular Surgery 2007;45(1):10-16.
DACRON® is a trademark of Invista, Inc., and is licensed to Unifi Inc.

Value of the Hemobahn/Viabahn Endoprosthesis in the
treatment of long chronic lesions of the superficial
femoral artery: 6 years of experience
Fischer M, Schwabe C, Schulte K-L. Value of the Hemobahn/Viabahn Endoprosthesis
in the treatment of long chronic lesions of the superficial femoral artery: 6 years of
experience. Journal of Endovascular Therapy 2006;13:281-290.
GORE, VIABAHN®, HEMOBAHN® , and designs are trademarks of W. L. Gore & Associates. © 2007 W. L. Gore & Associates, Inc.

SFA Stent Restenosis: How Common?
• 10 million PAD patients in U.S.
• 5 million with symptomatic lower extremity
occlusive disease
• >150,000 SFA Stent Procedures / Year
• Assuming restenosis rate of ~30%
(generous!), there are ~45,000 cases of
stent restenosis / year!

Treatment of Stent Restenosis with Viabahn
• Only FDA approved treatment for stent restenosis is
Balloon Angioplasty – safe, but poor patency results
• “Endovascular Bypass” may offer long-term patency
results similar to prosthetic fem-pop bypass
• FDA-Approved for use in SFA, though not
specifically for treatment of ISR (“off-label” use)
• SALVAGE Trial: Laser + Viabahn  discontinued

Rationale for use of Viabahn for ISR?
• Stent restenosis is often diffuse over a long-segment;
lesion length well-recognized predictor of restenosis
• Viabahn is only device for which restenosis is
independent of length of stented segment
• Restenosis can only occur at proximal or distal edge and
distance between those edges is irrelevant
• Very flexible stent does not “stiffen” vessel as much
as adding a second nitinol “laser-cut-tube” stent
• Virtually zero risk of subsequent stent fracture

Rationale for Pre-Viabahn Debulking
• Inadequate Viabahn Endograft expansion likely is a
predictor of restenosis and/or endograft thrombosis
• Without debulking, where does the plaque “go”
during PTA/Stenting?
• Nowhere! Mechanism of angioplasty is plaque
“compression” and stretching of vessel wall with stent
added to minimize recoil
• Vessel constrained by prior stent is unlikely to “stretch” very
much thereby limiting achievable lumen

Argument for Pre-Viabahn Debulking
• SALVAGE Trial recognized the synergy
between de-bulking and Viabahn endograft
placement for treatment of ISR
• Viabahn stent has only moderate radial
strength making debulking prior to stent
placement more important

SilverHawk / Viabahn for Stent Restenosis*
SilverHawk Post-Hawk Viabahn
*Off-Label Use

CONCLUSIONS (1): Gore Viabahn Endograft
• Excellent flexibility and fracture resistance
• Robust data confirms high long-term patency
rates
• Thrombosis rates further reduced by heparin
bonding and avoidance of smaller diameter stents
• Lack of restenosis ideal for long diffuse lesions
and long total occlusions since restenosis rate not
proportional to length of stented segment

CONCLUSIONS (2): Gore Viabahn Endograft
• Accurate deployment ideal for ostial lesions
• Moderate radial strength: May require pre-stent
debulking (“vessel prep”) when used in subintimal
space, in presence of highly calcific plaque, or for
tx of in-stent restenosis* (no supporting data)
• Viabahn stent thrombosis occurs infrequently…
but is highly treatable utilizing AngioJet /
PowerPulse Spray technique
* Off-label use

CONCLUSIONS (3): Gore Viabahn Endograft
• Treatment of restenosis of bare metal SFA stents
is a major problem, may represent up to 25% of
all SFA cases!
• Only FDA-approved treatment is balloon
angioplasty – clearly ineffective
• Viabahn stenting, preferably after debulking
strategy, likely is best option for treatment of this
challenging problem

CONCLUSIONS (4): Gore Viabahn Endograft
• Best treatment for bare metal stent restenosis:
PREVENTION!
• Primary use of Viabahn for SFA occlusive
disease, esp for long lesions and CTO’s is
excellent option… but if you didn’t use it then, you
can use it now!!!
• Future promising alternatives to reduce
restenosis:
• Drug-coated angioplasty balloons
• ?Drug-coated stents

Thank you for your
attention!
Barry S. Weinstock, MD, FACC
Orlando Health
Orlando Regional Medical Center
Orlando, Florida