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Closing Rem a rk s
In This
I S S U E
• C A S E S T U D Y
Understanding Atrial Septal Rim
Anatomy Using Echocardiography
Prior to Placement of the
GORE ® HELEX Septal Occluder
• F E A T U R E D T O P I C
Creating Products through
Collaborative Innovation
• I N T H E N E W S
Gore Provides Update on
Gore REDUCE Clinical Study
for Patent Foramen Ovale (PFO)
Closure
• U P C O M I N G E V E N T S
P E R F O R M A N C E b y d e s i g n
C A S E S T U D Y
Understanding Atrial Septal Rim Anatomy
Using Echocardiography Prior to Placement
of the GORE ® HELEX Septal Occluder
James W. Mathewson, MD, FACC, FASE
Eller Congenital Heart Institute, St. Joseph Hospital and Medical Center, Phoenix,
Arizona and the Northern Arizona Congenital Heart Center, Flagstaff, Arizona
The advent of devices for ASD closure without invasive surgery has prompted a need to more
fully understand the anatomy of the atrial septum. Successful closure requires the creation of
a “sandwich” wherein the left and right atrial components of the device (the bread) enclose
the rims (the meat) surrounding the defect. The absence of a large segment of rim can be
problematic. The purpose of this article is to describe how to echocardiographically visualize
atrial septal anatomy and point out those conditions wherein a surgical approach
is preferred.
The GORE ® HELEX Septal Occluder is pictured in Figure 1. Figure 2 shows its placement across
a hypothetical ideal ASD with fully deployed right and left atrial disks. The GORE ® HELEX
Septal Occluder is designed for closure of small to medium sized holes usually less than
2 cm in diameter. Before attempting to close such defects, one must first determine existing
ASD diameter, location, and rim anatomy.
Continued on inside cover...
Fall 2010 • Issue XI

Understanding Atrial Septal Rim Anatomy Using Echocardiography Prior
to Placement of the GORE ® HELEX Septal Occluder Continued from cover...
Figure 1. The GORE ® HELEX Septal Occluder.
Right Atrial Disk
Left Atrial Disk
Right
Superior
Vena Cava
Right
Atrium and
Appendage
Inferior
Vena Cava
Left
Innominate
Vein
Tricuspid
Valve
Figure 3. Frontal view of normal right atrial 3D
anatomy.
immediately behind the ascending aorta.
The AI, or antero-inferior rim, is located
just above the septal component of the
tricuspid valve. The PI, or postero-inferior
rim, is located along the back wall of the
atrium just superior to the entrance of the
inferior vena cava into the right atrium. The
PS, or postero-superior rim, is also located
along the posterior wall of the atrium but
superiorly and just adjacent to the entrance
of the right superior pulmonary vein into
the left atrium.
Prior to contemplating ASD closure
with any device, one must first identify
S.V.C.
Ao.
P.T.
Figure 2. Implanted GORE ® HELEX Septal Occluder
in hypothetical heart model.
Figures 3 and 4 show 3D computed
tomography images of normal human right
atrial anatomy together with the superior
vena cava, left innominate and azygous
veins. Figure 5 shows adjoining left atrial
anatomy (violet), tricuspid and mitral valves,
and the position of the interatrial septum.
Figure 6 depicts intra-atrial anatomy with
the anterior right atrial wall flapped open
to the right. Displayed are the positions
of the fossa ovalis (foramen ovale),
eustachian valve (VE), and the superior
and inferior vena cava. Note the position of
the ascending aorta which is anterior and
superior to the fossa ovalis, the location
of most secundum ASDs.
Atrial Septal Rim Anatomy
The rims surrounding an ASD in both
humans and canines can be divided
arbitrarily into five zones or regions
each of which is easily identified by
trans-thoracic (TTE), trans-esophageal
(TEE), and intracardiac echocardiographic
(ICE) methods. Figure 7 is an artist’s
rendering of these five rims and their
anatomic locations.
The locations of each rim can be
conceptualized in terms of their anatomic
positions relative to the anterior, posterior,
Tricuspid
Valve
Azygous
Vein
Atrial
Septum
Figure 4. Left side view of normal right atrium.
Plane
of Atrial
Septum
Tricuspid
Valve
Appendage
Mitral Valve
Figure 5. Right and left atria together in situ.
superior, and inferior orientation of the
heart as it sits in the chest. The S or superior
rim is located just inferior to the entrance of
the superior vena cava into the right atrium
and below the right pulmonary artery as
it passes behind the superior vena cava.
The AS, or antero-superior rim, is located
P.C.B.
F.O.
C.S.
R.V.
V.E.
R.C.A.
Figure 6. Atrial septal anatomy with RA free wall
opened to right (arrows): Ao: aorta; CS: coronary
sinus; FO: fossa ovalis; PT: pulmonary trunk; RCA:
right coronary artery; RV: right ventricle; SVC:
superior vena cava; VE; eustachian valve.
RUPV
SVC
PS
IVC
PI
S
AS
AI
AAO
P
Tricuspid Valve
Septal Leaflet
Figure 7. Artist’s rendering of the five septal rims.
A: anterior; AAo: ascending aorta; AS: anterosuperior
rim; AI: antero-inferior rim; I: inferior;
IVC: inferior vena cava; P: posterior; PI: posteroinferior
rim; PS: postero-superior rim; RUPV: right
upper pulmonary vein; S: superior rim; SVC:
superior vena cava.
I
S
A

Right Upper
Pulmonary
Vein
PS Rim
AI Rim
Crux
S Rim
PI Rim
AS Rim
PS Rim
AI Rim
Crux
S Rim
PI Rim
AS Rim
Figure 8. TTE apical four chamber view; beam cuts
front to back from apex in front to the upper atria
posteriorly.
these five rims to be sure there is adequate
rim to retain the device. Because the most
common imaging modalities used at or prior
to the time of device placement are TE and
trans-esophageal echocardiography TEE,
this report will emphasize how each rim is
identified using these two technologies.
Trans-Thoracic Echocardiography-TTE
For TTE, the pertinent views for seeing the
five rims are apical four chamber (AI and PS
rims), para-sternal short axis (AS rim), and
sub-costal long axis (S and PI rims). Figure
8 shows a typical apical four chamber view
which cuts the heart from the ventricular
apex in front to the posterior superior atrial
base at the level of insertion of the right
and left upper pulmonary veins. The AI rim
is adjacent to the AV valve insertion into the
crux of the heart. The PS rim is just proximal
to insertion of the right upper pulmonary
vein into the left atrium.
The PI and S rims are identified from the
sub-costal long axis view as seen in Figure
9. In this view, the superior and inferior
vena cava are intersected together with the
long axis of the right atrium. One identifies
the superior rim just beneath the right
pulmonary artery as it passes behind the
Figure 9. TTE sub-costal long axis cuts through
IVC, SVC, and RA showing S and PI rims.
superior vena cava. The postero-inferior
rim is also identified as it joins the
postero-inferior back wall of the left atrium.
The fifth rim, the AS rim, is located just
behind the ascending aorta and is identified
from standard para-sternal short axis
views as depicted in Figure 10. It should
be remembered that roughly 45% of all
secundum ASDs are located anteriorly and
superiorly behind the aorta rather than
centrally near the fossa ovalis (Figure 6).
Trans-Esophageal
Echocardiography-TEE
In most children weighing 15 kg or more,
a standard adult multi-plane probe may
be safely inserted. For those weighing less
than 15 kg, an 8 mm multi-plane pediatric
probe is appropriate. The most important
aspect of probe placement is pulling the
lower mandible up and forward before the
probe tip is inserted. The probe tip is then
advanced to the level of the left atrium
before proceeding. Ideally one should
utilize a multi-plane probe which can rotate
the beam from 0 degrees through +90
degrees. Limiting rotation to 0 degrees to
+90 degrees ensures constant right-left
Figure 10. TTE parasternal short axis demonstrating
the AS rim behind the ascending aorta.
orientation. Rotating beyond 90 degrees
will reverse right-left relationships. In order
to see the left and right atrial disks after
deployment together with the sandwiched
rims in between, one must see the disks
perpendicular to the delivery sheath. This
requires the ability to see the sheath at
roughly 40 degrees to 80 degrees, the
angle at which the sheath enters the heart
from the inferior vena cava. Figure 11 is an
artist’s rendering of the delivery sheath and
deployed left atrial disk within the heart.
Note that the plane of the disk is not 90
degrees to the plane of the sheath (Figure
12). If a biplane probe is used, the sheath
will not be visualized along its long axis
obviating the ability to see the deployed
disks perpendicular to the sheath and
parallel to the enclosed septal rims.
Step one is to identify the AI and PS rims.
This is done by visualizing the heart from
directly behind the left atrium at 0 degrees.
A standard four chamber view is produced
which orients the left heart structures to
the observer’s right and the right sided
structures on the observer’s left. This view
cuts the heart from the posterior superior
aspect where the right and left upper

pulmonary veins enter the left atrium to the
apex of the ventricles which is anterior and
inferior as the heart sits in the chest (Figures
13 – 16). This view is analogous (although
the antero-posterior reverse) to the standard
trans-thoracic four chamber view.
Figure 15 shows a pathology specimen with
severe left ventricular hypertrophy with the
heart cut at 0 degrees exactly along the
same plane subtended by the TEE probe.
The cut is from the posterior superior aspect
of the left atrium near the entrance of the
right upper pulmonary vein to the apex of
the left ventricle anteriorly and inferiorly,
hence the designation of the posterosuperior
and antero-inferior rims of the
atrial septum. Figure 17 shows absence of
the PS rim. Such defects if larger than about
2 cm require surgical closure. The largest
GORE ® HELEX Septal Occluder available is
too small to close defects of this size, and
closure with other commercially available
devices may not be suitable due to the risk
of erosion through the posterior atrial wall
from an obligatorily oversized device.
Step two is to identify the S and PI rims.
Figure 18 shows that a vertically oriented
plane will cut through both rims. By rotating
the probe to roughly +90 degrees (Figure
19), a plane will be created that will cut
through the superior vena cava, right
atrium, and inferior vena cava. This
SVC
PS
IVC
PI
S
AS
AI
AAO
Figure 13. 0 degrees plane of the probe cuts the
PS and AI rims.
view is analogous to the trans-thoracic
sub-coastal long axis view. Figure 19 (inset)
shows the probe oriented in this fashion.
By limiting rotation to +90 degrees, one will
obligatorily orient the superior vena cava to
the right with the inferior vena cava to the
left (Figures 19, 20). This 90 degree view is
the most important of all views because it is
the only way to visualize the postero-inferior
rim. Figure 21 demonstrates absence of
the postero-inferior rim which results in an
Postero-superior
Atrial Septal Rim
Antero-inferior
Atrial Rim
Figure 16. Standard four chamber view at 0
degrees.
LA
Figure 11. Left atrial disk deployed. The angle of
entrance of the sheath into the RA lies between
40 degrees and 80 degrees.
RA
RV
LV
Figure 17. Absent PS rim. Blue color represents
blood flow from LA to RA across ASD.
70˚
Figure 12. Note plane of atrial septum (yellow
arrow) compared to probe angle of 70 degrees
which shows the long axis of the sheath (green)
with the LA disk perpendicular to the sheath.
D
Figure 14. At 0 degrees, a four chamber view is
obtained.
Entrance of Right
Upper Pulmonary Vein
RA
Postero-superior
Atrial Septal Rim
LA
Antero-inferior
Atrial Rim
Figure 15. Pathology specimen cut at 0 degrees.
SVC
PS
IVC
PI
S
AS
AI
AAO
Figure 18. Vertical orientation of probe plane to
intercept the superior and postero-inferior rims.

A
Posterior-inferior
Rim
Superior Rim
Posterior-inferior
Rim
Superior LA Rim RPA
LA
IVC
RPA
SVC
IVC
RA
SVC
A
RA
Figure 19. Probe at roughly +90 degrees cuts the
RA vertically through the SVC, RA, and IVC.
Antero-superior
Rim
Antero-superior LA
Rim
RA
B
RA
B
RVOT
LA
AoV
RVOT
AoV
Tricuspid
Valve
Aortic
Valve
Absent
AS Rim
Figure 24. Probe at 15 degrees showing absent
AS rim.
Tricuspid
Valve
Absent PI Rim
S Rim
Aortic
Valve
Superior Rim
Absent
RPA
AS Rim
Postero-inferior Rim
SVC
Figure 20. At 81 degrees with SVC to right, IVC to left.
Figure 21. Absent PI rim with huge 3 cm diameter ASD.
inferior sinus venosus ASD which cannot be
closed with any device now available. Such
defects often include absence of portions of
the postero-superior rim near the entrance
of the right upper pulmonary vein into the
left atrium as well as the antero-superior
rim behind the aorta. These ASDs often
exceed 2.5 cm in diameter. If one looks
only in the horizontal plane, the ASD may
appear deceptively central in location with
Figure 22. Probe at 15 degrees to see antero-superior
rim AoV: aortic valve; RA: right atrium; RVOT:
right ventricular Absent PI Rim outflow tract; LA; left atrium.
S Rim
Present
AS Rim
Aortic
Valve
Tricuspid
Valve
Figure 23. AS rim present.
a diameter that may appear ideal for GORE ®
HELEX Septal Occluder closure. But like an
iceberg, the bulk of the opening is below the
four chamber plane, and deployment and
subsequent release of a device may lead
to embolization. The last step is to identify
the AS rim behind the aorta by rotating the
probe to +15 degrees to 65 degrees which
orients the beam parallel to the aortic valve.
Figure 22 displays the probe orientation
and the resultant artist’s rendering of the
view obtained. One notes that this image is
analogous to the trans-thoracic para-sternal
short axis view. Figure 23 shows a centrally
located ASD with present AS rim. Figure 24,
in contrast, shows a more typical secundum
ASD with complete absence of the AS rim.
Is Rim Documentation Necessary?
Why is it necessary to identify and measure
all five rims before attempting to insert and
release the GORE ® HELEX Septal Occluder?
If adequate rim is present completely
surrounding the ASD and provided the
diameter is less than 18 mm, the opening
can almost always be closed using the
GORE ® HELEX Septal Occluder. Absence
of the superior rim results in a high sinus
venosus ASD which is commonly associated
with partial anomalous pulmonary venous
connection of the right upper and / or
middle pulmonary veins to the superior
vena cava. Obviously, such holes require a
surgical approach. If the AS rim is absent,
the hole can still be closed provided the
other four rims are present. The device
is sized and positioned such that the AS
portions of the right and left atrial disks hug
the posterior wall of the ascending aorta
as if one is surrounding a tree trunk with
one’s arms. Absence of the AI rim results in
a form of endocardial cushion defect known
as an ostium primum ASD. Since the hole
is located immediately above the AV valves
with no intervening tissue, a deployed
device will obligatorily be in contact with
AV valve tissue. Closure with any available
device is currently not possible. Holes in the
region inferiorly between the AI and PI rims
are termed coronary sinus ASDs and are
not closeable using interventional devices.
Absence of the postero-inferior rim results in
an inferior type sinus venosus atrial septal
defect. As noted, such openings are often
very large sometimes exceeding 3 cm in
diameter and require surgery to safely close.
Absence of the postero-superior rim alone
is problematic. If the diameter of the hole
is less than about 16 – 20 mm, the hole
may be closeable. Larger diameter holes
are not closeable with the GORE ® HELEX
Septal Occluder. Holes that are more or less
centrally located or positioned anteriorly
and superiorly behind the aorta with
adequate surrounding rims are best suited
to be closed safely with the GORE ® HELEX
Septal Occluder.

F E A T U R E D T O P I C
Creating Products through Collaborative Innovation
Collaboration Leads to Innovation
When business strategist Dan Burrus visited
Gore to speak at an innovation conference
in 2008, he noticed something unique about
the way the company interacts with its
customers. As Gore product specialist Bob
Sassa recalls, “He referred to Gore as the
‘master of collaborative innovation,’ because
we like to work closely with customers to
develop products that meet their needs.”
To do this effectively, associates often ask
customers numerous questions, play an
active role in problem-solving and even
work alongside them in their facilities. Dan
pointed out that few companies collaborate
so openly, and some customers might not
understand or feel comfortable with this
unique approach. His feedback spurred Bob
and a team of fellow associates to create
videos highlighting Gore’s collaborative
innovation process. “A collaborative
relationship requires a lot of trust from
each party,” says Gore project core team
member Betty Snyder. “We wanted to
create something that would help new and
prospective customers understand why we
work this way.” The videos, filmed by Gore
“
Associate Curtis King highlight real life
examples of Gore’s work with customers on
new product innovation.
Examples include:
• Creation of a fiber that increases the
service life of ropes in high-stress
applications
• Enhancement of an implantable
medical material used in hernia repair
• Development of a fabric and ensemble
that protects against chemicals and
biological agents
• Creation of a material that reduces
the heat generated by thin notebook
computer processors
• Development of a filter that captures
particulate matter and destroys toxic
dioxins and furans
Customer Collaboration
Each story features the customers’ and
associates’ perspectives of their experiences
working together. “These videos show that
we’re way more than simply a provider of
products,” Curtis says. “We work hard to
understand the technical issues that are
keeping our customers up at night. Our
philosophy is to be the problem solver.” Gore
project core team member Gordon McGregor
says it’s helpful to receive feedback from
customers on Gore’s approach. Customers
express many common viewpoints in the
videos, including the level of trust they
place in the company and how much they’ve
benefited from their close collaboration
with Gore. Comments included: “Gore is a
company that will allow you to get to your
goal,” and “I would [work with Gore] again in
a heartbeat.” “They talked from the heart,”
Gordon says of the customers. “It feels good
to see that we’re delivering on the things
they’re looking for, and that we’re really
adding value to their products. They all said
they had a great experience with us, and
that’s exactly what we’re trying to deliver.”
Note: Ask your local Gore Sales Associate for the
full collaborative innovation DVD. Video files are
available in our online version of Closing Remarks:
http://www.goremedical.com/helex/library/
newsletters
We work hard to understand the technical issues that are keeping our customers up
at night. Our philosophy is to be the problem solver. — Curtis King
”
The image above features the GORE ® BIO-A ® Tissue Reinforcement collaborative video. The DVD includes five-minute Collaborative Innovation video segments
spotlighting examples of Gore’s work with customers on new product innovation. The segments include GORE OMNIBEND Fiber, GORE ® BIO-A ® Tissue Reinforcement,
GORE ® CHEMPAK ® Fabric, GORE Thermal Interface Material and GORE ® REMEDIA ® Catalytic Filtration Systems.

I N T H E N E W S
Gore Provides Update on Gore REDUCE Clinical Study
for Patent Foramen Ovale (PFO) Closure
The Gore REDUCE Clinical Study* is a prospective, randomized, multi-center, multinational
trial designed to demonstrate safety and effectiveness of the GORE ® HELEX Septal
Occluder for Patent Foramen Ovale (PFO) closure in patients with history of cryptogenic
stroke or imaging-confirmed Transient Ischemic Attack (TIA). The unique study, which
includes up to 50 investigational sites in the US and in Europe, is estimated to meet its
completion in 2014.
“In light of the recent press release regarding the preliminary results of CLOSURE I, we
felt it important to re-emphasize our confidence in the design and expected outcome
of the Gore REDUCE Clinical Study,” said Stuart Broyles, PhD, Associate with the Gore
Medical Division Stroke Business. “Due to our European experience regarding the clinical
performance of the GORE ® HELEX Septal Occluder and our unique study design, we remain
very confident that the Gore REDUCE Clinical Study will ultimately achieve its intended
objective. We are committed to the completion of this study and the pursuit of an FDA
indication for PFO closure and the prevention of recurrent stroke.”
According to Scott Kasner, MD, Professor of Neurology and Director of the Comprehensive
Stroke Center at the University of Pennsylvania Medical Center, and US Neurology
Principal Investigator, “The design of the Gore REDUCE Clinical Study is unique from the
other PFO stroke trials in several respects. First, Magnetic Resonance Imaging (MRI) of the
brain will be performed on all patients at baseline and at two years. This feature offers
an additional imaging endpoint for making comparisons between the treatment arms.
Second, it focuses on secondary prevention of stroke rather than TIA, which improves the
reliability of the study outcomes and measurably impacts the public health. Finally, this
is a multinational study, which enhances its global applicability. These efforts will likely
help resolve the open debate about whether PFO closure is a viable option for treating
cryptogenic stroke / TIA patients as compared to medical treatment
alone, as it is used today.”
The Gore REDUCE Clinical Study has several unique features: participation of Nordic
investigational sites, the use of imaging-confirmed stroke / TIA for assessing its primary
endpoint, a 2:1 device to medical management randomization strategy, a standardization
of medical therapies across treatment arms, and the use of the GORE ® HELEX Septal
Occluder. Recruitment in the Nordic countries, where patients may be more willing to
be randomized, is projected to help drive study enrollment. Additionally, Gore is in the
process of recruiting sites in the United Kingdom to participate in the Gore REDUCE
Clinical Study. MRI will be used to evaluate all patients in the trial to more accurately
confirm the presence of stroke and TIA. Additionally, the standardization of medical
therapies across treatment arms will further aid the interpretation of the final results in
assessing the potential benefit of device closure for the prevention of recurrent stroke.
The GORE ® HELEX Septal Occluder was approved by the US Food and Drug Administration
(FDA) in 2006 for treatment of Atrial Septal Defect (ASD), a congenital heart defect. The
GORE ® HELEX Septal Occluder is the first device of its kind to use ePTFE, a biocompatible
material that allows progressive tissue ingrowth, to help seal the defect.
*REDUCE: GORE ® HELEX Septal Occluder plus Anti-platelet Medical Management for
Reduction of Recurrent Stroke or Imaging-Confirmed TIA in Patients with PFO.
Visit http://www.clinicaltrials.gov for more information.
“
We are committed to
the completion of this
study and the pursuit
of an FDA indication for
PFO closure and the
prevention of recurrent
stroke.
”
— Stuart Boyles, PhD
Caution: Investigational Device. Limited by United States Law to Investigational Use For the Indication described in this article.

U P C O M I N G E V E N T S
Please Join Us...
SCAI Fall Fellows Program
Gore Structural Heart Disease and Stroke Symposium
December 5 – 6
Las Vegas, Nevada
2010 Scheduled GORE MEDICAL MASTERY SERIES Courses Sponsored by Gore
October 13 – 14 Chicago Atrial Septal Defect Closure Course with a Lab
October 21 – 22* Philadelphia Atrial Septal Defect Closure Course with a Lab
October 28 – 29 San Diego Introduction Atrial Septal Defect Closure
December 3* Detroit Complex Atrial Septal Defect Closure
Gore’s commitment to excellence continues with the GORE MEDICAL MASTERY SERIES.
The Atrial Septal Defect Closure courses provide Interventional Cardiologists with the
opportunity to develop their knowledge of implant techniques. Contact your local Gore
Sales Associate for further information regarding these various course opportunities.
* enrollment full
If you have a topic that you would like us to consider in a future issue of Closing Remarks,
please contact your local Gore Sales Associate or e-mail ClosingRemarks@wlgore.com
W. L. Gore & Associates, Inc.
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+65.67332882 (Asia Pacific) 800.437.8181 (United States)
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INDICATIONS FOR USE IN THE US: The GORE HELEX Septal Occluder is a permanently implanted prosthesis indicated for the percutaneous, transcatheter
closure of ostium secundum atrial septal defects (ASDs). INDICATIONS FOR USE UNDER CE MARK: The GORE HELEX Septal Occluder is a permanently
implanted prosthesis indicated for the percutaneous, transcatheter closure of atrial septal defects (ASDs), such as ostium secundum and patent foramen
ovale. Refer to Instructions for Use at goremedical.com for a complete description of all contraindications, warnings, precautions and adverse events.
Products listed may not be available in all markets.
GORE ® , BIO-A ® , CHEMPACK ® , HELEX, OMNIBEND, PERFORMANCE BY DESIGN, REMEDIA ® , and designs are trademarks of W. L. Gore & Associates.
© 2010 W. L. Gore & Associates, Inc. AP4476-EN1 AUGUST 2010