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R. Gallet and E. Teiger
Decision Making onTechnique Selection
Do date, the most used (and almost only available) technique
for percutaneous mitral repair is TEER. Other techniques
such as percutaneous annulopasty [23] and trans-apical neochordae [24, 25] implantation are being developed but have
not been fully tested and are not recommended yet. Direct
percutaneous annuloplasty is currently a lesser known technique. Indeed, it has been studied only in a small CE approval
study and in case reports. This technique is complicated and
associated with very long procedural times. Moreover, it
allows treatment of secondary MR, with disappointing
results regarding MR reduction (40% mild or less MR at
1year) [23]. Neochordae implantation offers the opportunity
to treat primary MR but is not completely percutaneous since
it requires a trans-apical approach [24, 25]. For all these reasons, only TEER especially using the MitraClip system will
be discussed for the procedural technique.
The MitraClip device is now in its fourth generation with
an independent grasping mechanism [26]. It is available in
four sizes depending on its length (NT or XT MitraClip with
arms respectively 9 and 12mm long) and its width, each
length being available with 2 widths in the grasping area
(4mm wide, NT and XT MitraClip, or 6mm wide, NTW and
XTW MitraClip). Long clips offer more possibility for the
grasping of large coaptation defects but require a sufcient
length of valve to be captured in the clip (>10 mm).
Additionally, they provide more tension of the valve, resulting in a certain degree of annuloplasty. A larger clip allows
for treatment of larger prolapse and reduction of the number
of clips implanted.
Pre-procedural Therapeutic Strategy
andNumber ofClips
Pre-procedural strategy will aim to determine the number of
clips to be implanted and their location. While small prolapse may be treated using only one clip, larger prolapse and
secondary MR usually require two or three clips. When
implanting several clip, it is always easier to start with the
more medial clip and then to implant the other clip(s) more
laterally. Thus, after implantation of the rst clip, no residual
signicant MR should be present on the medial side of the
clip. One exception to this strategy is the treatment of anterolateral commissural ail. In this case, the most commissural
clip will be implanted rst.
Access totheLeft Atrium
All procedures will be performed under general anesthesia
and TEE guidance. Access to the left atrium will require
femoral vein approach (usually the right one for easier transseptal puncture).
Septal puncture will be performed under TEE guidance in
order to cross the septum at the proper position to make the
TEER easier.
After venous access using a 5–8 Fr sheath, a 0.032-inch
wire will be positioned in the superior vena cava. A transseptal sheath will be approached over this wire. A BRK- transseptal needle will be introduced into the trans-septal sheath.
Using biplanar TEE guidance the puncture of the septum will
be performed on the upper and posterior area of the inter-atrial
septum. The biplanar TEE mode will allow both the bi-caval(to
monitor the superior/inferior position) and the aorta (to monitor the anterior/posterior position) to be viewed at the same
time. After visualization of the tenting on the fossa ovale at the
intended position, the latter will be controlled in the fourchamber view in which the distance between the tenting and
the mitral annular plan will be measured. To ensure that the
grasping will be possible, this distance will have to be between
40 and 45mm with high puncture for primary as compared to
secondary MR.The distances are different because of the different plan of coaptation (lower in primary MR because of the
prolapse, higher in the LV in secondary MR because of the
tenting). After measurement, the septum will be punctured, the
needle will be removed and the 0.032-inch wire will be
advanced into the pulmonary artery and then changed for a
0.035-inch stiff wire.
An alternative to the use of the BRK needle is to use a
dedicated wire connected to a radiofrequency generator. This
pre-shape wire will be used instead of the needle to cross the
septum thanks to radiofrequency. The guidewire will be
positioned into the left atrium. Then, its stiffness will allow it
to advance any material without any trauma.
Anticoagulation
All TEER procedures require anticoagulation aiming at an
ACT value over 250. Unfractionated heparin with an initial
dosing of 100U/kg is usually used and can be administrated
with two different schema, either full dose after the transseptal puncture (after ensuring that there is no trans-septal
crossing-related adverse event) or half of the dose before
trans-septal puncture and half of the dose after. ACT will
then be monitored every 20min.
ab
cd
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Access totheMitral Valve
the unit, and then returned to the neutral position once positioned in the right atrium to be oriented toward the left
The MitraClip system is composed of two different parts, a
steerable guide catheter (24French (8.1mm), 800mm working length) that will be held by a stabilizer, and a clip delivery system.
The guide catheter will be advanced to the left atrium over
the 0.035-inch stiff wire. On initial skin and vessel entry, the
atrium. The guide catheter is then advanced about 1–2cm
into the left atrium, and the wire and the dilator of the guide
catheter will subsequently be removed (Fig.41.1a). Once the
guide is positioned into the left atrium, the clip delivery
system will be introduced through the guide and the markers
of the guide will be aligned with the marker of the delivery
+/− knob of the guide catheter is turned toward—to straighten
Fig. 41.1 (a) MitraClip steerable guide catheter positioned into the left
atrium (angiographic view). (b) MitraClip out of the guide cathter, into
the left atrium (angiographic view). (c) MitraClip facing the mitral
valve (angiographic view). (d) positioning of the MitraClip into the
regurgitant jet (color doppler)
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R. Gallet and E. Teiger
system (“straddling”) with attention paid to the left atrium
wall while taking the clip out of the guide (Fig.41.1b).
The clip will then be directed toward the mitral annulus,
mainly by applying medial deection on the delivery system
using its M/L knob (Fig. 41.1c). Concomitantly, posterior
orientation of delivery system will be used to move the clip
away from the upper left pulmonary vein and the left atrium,
so as not to get trapped in one of these two structures while
moving the clip toward the annulus. All these maneuvers will
be performed with the clip stuck to the delivery system (so
called slacked). Once the clip is facing the mitral annulus,
approximately 1 cm above the coaptation plan, it will be
aligned with the regurgitant jet using a TEE multiplanar view
showing LVOT (for antero-posterior assessment) and bicommissural view (for medial/lateral assessment)
(Fig. 41.1d). This antero-posterior alignment will be performed using the counter-clockwise/clockwise rotation of
the guide catheter. Medial-lateral alignment can be performed using the M/L knob of the clip delivery system or the
+/− knob of the guide catheter (+ brings the clip more
medial) or by pulling/pushing the guide catheter/clip delivery system couple (pulling brings the clip more medial). The
action to apply will depend on a combination of factors
including the adequate orientation of the clip in relation to
the predicted grasping area and to the aorta and the length of
delivery system into the left atrium. The aim will be to be
positioned into the regurgitant jet at the scheduled position
(depending on the number of clips to be implanted) but also
to be perpendicular to the intended area of grasping to have a
proper grasping. Thus, the trajectory of the clip when it is
moved forward will be assessed to make sure it does not
change its position when it is advanced.
When the clip is at the right position, the arm of the clip
will be opened (with the grippers being up, i.e., on the delivery system) at 120° and the clip will be oriented perpendicular to the line of coaptation in a 3D en face view of the mitral
valve. Orientation will be achieved using counter-clockwise/
clockwise rotation of the clip delivery system handle (with
concomitant small back and forth movement in order to
translate the movement to the clip). When the clip is perpendicular to the line of coaptation, its position as well as its
trajectory when its advanced will be checked one last time.
The clip will then be closed at least 60° and advanced to
cross the mitral valve.
Grasping oftheLeaet
Once in the left ventricle (not too deep to avoid injuring any
chordae), the clip will be reopened to 120–150°, depending
on the coaptation. The position and perpendicularity will be
checked and the clip will be gently pulled up until both the
anterior and posterior leaets fall into the arm of the clip
with restrictive opening due to the clip arms (Fig.41.2a).
Once the position is conrmed for both leaets, the grippers will be lowered to trap the leaets between the clip and
the grippers. The proper grasping will be conrmed using
different methods; rst the echo cine of the grasping will be
reviewed to make sure there is enough tissue into the clip.
The length of leaet into the clip will also be measured
either directly (but this requires high-quality imaging) or
by subtracting the residual length of the leaet after grasping to its initial length. Lastly, the grippers should be moving with the movement of the valve, indicating that the
leaet is between the clip and the gripper. The clip will be
closed to 60° (Fig. 41.2b), the delivery system will be
advanced by a few mm to reduce tension, and the initial
results on the MR will be assessed as well as the transvalvular gradient.
It is crucial to make sure that both leaets have been adequately captured. Indeed, incomplete capture will likely lead
to clip detachment from the leaet and MR relapse or even
clip embolization.
Once satisfactory clip placement and leaet grasp have
been conrmed, the clip will be locked and further closed
under TEE color mode to monitor an additional reduction of
the MR.Once the placement and results are deemed optimal,
the clip will be released (Fig.41.3).
Troubleshooting
Clip Too Deep or Too High intheLeft Atrium
In some cases, the grasping of the leaets cannot be performed either because the clip is too high (and not able to
cross the mitral valve) or more often too deep, resulting in
the impossibility of applying enough tension on the leaet
during the grasping. This can be related to an inadequate
trans-septal crossing location. If trans-septal is adequate or
cannot be performed again, the height of the clip can be
adjusted using the A/P knob on the clip delivery system. The
A rotation will bring the clip higher (and more anterior with
a need to adjust the position) while the P rotation will bring
the clip deeper (and more posterior). This maneuver has to
be performed into the left atrium and not into the left
ventricle.
Incomplete or Dicult Grasping ofOne
oftheLeaets
The Gen 4 MitraClip allows separate grasping of the leaet
[26]. The grippers can be lowered separately. This can be
used to optimize the grasping of one of the leaets; the clip
will be opened, the gripper will be lifted up, and the handle
will be rotated toward the target leaet (anterior or posterior)
with a gentle traction. The gripper will then be lowered and
the clip closed. Caution must be taken to make very small
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Fig. 41.2 (a) Position of the
clip just before grasping on
biplanar TEE view
(bicomissural and LVOT).
Both the anterior and
posterior leaets into the arms
of the clip are shown. (b) Clip
closed at 60° on biplanar TEE
view
453
a
b
and gentle movements to avoid any damage on the captured
leaet. This technique can also be used for separate grasping
in case of a large coaptation defect.
Another technique to grasp the leaets in case of large
coaptation defects is the zipping technique. This technique
requires multiple clip implantation. The rst one will be
implanted at the edge of the coaptation defect where the leaflets are almost coapting. This grasping will be easier to perform and will bring the leaet closer for the implantation of
one or more additional clips.
Need toRemove theClip andDelivery System
fromtheLV
Every time a clip has to be removed from the LV (attached to
the delivery system, there is currently no percutaneous solution to remove a launched clip), this will have to be performed with the clip in an inverted position.
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Fig. 41.3 MitraClip released (angiographic view)
Other Devices
Other devices are available in the market but are not as evidenced as the MitraClip device. For TEER the Pascal device
is undergoing investigations [22, 27]. Other techniques exist
such as annuloplasty using the Cardioband system or transapical neo-chordae implantation but these devices have only
been used in small studies (mainly CE marking studies) and
have not been compared to other treatments (medical, surgical, or interventional) [23–25].
Vascular Closure
Vascular closure may be obtained using two proglides positioned using the preclosing technique [28]. Alternatively,
venous compression using a gure eight stich is also
efcient.
Anticipated Complications
R. Gallet and E. Teiger
Vascular Injury
Vascular injury can occur in every percutaneous procedure.
In the case of TEER, venous perforation (inferior vena cava
or external or common iliac vein) with the guide catheter
usually has a poor outcome because of the rapid and massive
associated bleeding and the impossibility of achieving adequate hemostasis. To avoid vascular complications,
ultrasound- guided punctures are strongly recommended. For
the introduction of the guide catheter a stiff wire is mandatory and pre-dilatation of the skin and the vessel with dilators
(14Fr, 18Fr, and 22Fr) should be performed.
Trans-septal Puncture Complication
The use of TEE guiding enables safer puncture of the interatrial septum. However, aortic puncture or tamponade may
sometimes occur. Depending on the size of the breach, the
treatment will go from close monitoring to emergent cardiac
surgery. To avoid any complication, the puncture must be
echo-guided using multiplanar TEE. The needle will be
pushed out of the trans-septal sheath only if tenting on the
inter-atrial septum is visible on both plans in TEE.In case of
thick or very oppy septum, several techniques can be used
to secure the puncture. Radiofrequency can be used directly
on the needle using an electric scalpel or using dedicated
trans-septal wires. Another technique is to use a 0.014-inch
wire introduced in the needle from the proximal segment to
cross and the septum. The needle will then be advanced over
the wire.
Pulmonary Vein or Left Atrium Appendage
(LAA) Injury
Pulmonary vein or LAA injury may be caused by the stiff
guidewire, by the guide catheter, or by the clip delivery system. Pulmonary vein injury (usually upper left pulmonary
vein) will be suspected if blood is present in the endo- tracheal
tube or if ventilation becomes more difcult, while LAA
injury will result in cardiac tamponade. Both situations will
require emergency assessment and treatment.
Several complications can occur at each step of the procedure. Although rare, most of them can have dramatic
outcomes.
Intra-cardiac Thrombus
Intra-cardiac thrombus can appear during the procedure
especially on the intra-cardiac material. While pre-existing
intra-cardiac thrombus is a contra-indication to TEER, appa-
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455
rition of an intra-cardiac thrombus should lead to reconsideration of the procedure. ACT should be maintained >250 to
avoid any thrombus formation and all catheter lumen should
be regularly ushed.
Chordae Coiling Around theClip
Excessive manipulation of the clip in the left ventricle, especially in the commissural area, can lead to entrapment of the
clip in the sub-valvular apparatus. When this situation occurs,
the rst step should be to reverse the preceding maneuvers.
The clip should be inverted and gently torqued or advanced
into the LV.If the clip remains attached to the chordae despite
the maneuvers, it may be safer to deploy the clip into the
coiled sub-valvular mitral apparatus.
Leaet Detachment
If there is not enough tissue grasped into the clip, singleleaet detachment may occur. If the clip has not started to be
released, another grasping can be performed. However, if the
clip has been released, there is no possibility to extract the
clip besides surgery. If the grasping of the other leaet is
stable, it may be considered to leave the clip in place and
stabilize it with the implantation of a nearby additional clip.
Reduction inMitral Valve Area
Due to the mechanism of mitral valve repair, MitraClip
implantation will reduce the effective mitral valve area.
Before releasing the clip, transvalvular mitral gradient will
be measured and any gradient higher than 5mmHg will raise
concerns about removing this clip on a risk/benet ratio.
Preliminary studies regarding the impact of higher postMitraClip gradients are to date reassuring [29] but data are
sparse.
Perioperative Care andSurveillance
The patient should remain on bed rest for 2–4h to allow for
recovery from the anesthesia as well as hemostasis. Given
the reduction of the MR and the uid expansion received
during the procedures, attention should be paid to worsening
of the left ventricular ejection fraction especially in patients
with pre-existing LV dysfunction, and to pulmonary edema.
Diuretics should be administrated in case of clinical symptoms or echographic signs of increased lling pressures.
In patients with indication for anticoagulation (for atrial
brillation notably), the latter should be restarted the evening
after the procedure or the next day and pursued. In patients
without anticoagulant, dual anti-platelet therapy should be
administrated for 3months followed by aspirin alone.
Follow-up ofce visit is recommended at 3, 6, and
12 months and annually thereafter with trans-thoracic
echocardiography.
Case Presentation
Continued from page 453
A MitraClip was planned within a few days under general
anesthesia and TEE and uoroscopic guidance. Under ultrasound guidance, venous access was obtained. Pre-closing
was performed using two preclose proglides. Trans-septal
puncture was made using an SL0 trans- septal sheath and a
BRK needle. The puncture was made on the upper and posterior part of the septum and the distance between the transeptal crossing and the annulus plan was measured at 41mm.
After conrmation of the absence of complication of the septal puncture, heparin was injected with regular boluses as
needed to maintain an ACT≥250ms.
An XTW clip was chosen in order to treat the whole prolapse with only one clip. The clip was advanced and oriented
toward the mitral annulus, oriented perpendicular to the
valve, and then advanced into the LV.The clip was deployed
at the intended position and allowed the grasping of the ail
A2 and the posterior leaet. After implantation of this clip
there was no residual area of prolapse and the MR was
graded as 1/4.
The pulmonary systolic pressure had already decreased to
30mmHg the next day and the patient was safely discharged
24h after the procedure.
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7. Feldman T, etal. Randomized comparison of percutaneous repair
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Atrial Septal Defect: Left Atrial
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Appendage
MariaDrakopoulou, AnastasiosApostolos,
IoannisKachrimanidis, GeorgiosOikonomou,
LeonidasKoliastasis, GeorgiosTrantalis, CostasTsious,
andKonstantinosToutouzas
42
Abbreviations
ACT Activated clotting time
AF Atrial brillation
ASD Atrial septal defect
LAA Left atrial appendage
MDCT Multidetector computed tomography
OAC Oral anticoagulation
PAH Pulmonary arterial hypertension
PVR Pulmonary vascular resistance
TOE Transoesophageal echocardiography
Atrial Septal Defect
Case Presentation
A 31-year-old female patient with no past medical history
presented with exertional dyspnea and intermittent palpitations of 6-month duration. Physical examination revealed
heart rate 110/min and blood pressure 130/72mmHg with
oxygen saturation 98% on room air with normal jugular
venous pressure (JVP). The heart rhythm was regular and
there was no left parasternal heave on palpation. The pulmonary component of the second heart sound was delayed and
xed. There was a soft systolic ejection murmur at the upper
left sternal border. Regular heart with rhythm was regular.
The electrocardiogram showed sinus rhythm with incomplete right bundle branch block. Biochemical and hematological investigations were within normal limit. Chest x-ray
was suggestive of cardiomegaly. Transthoracic echocardiography showed normal left ventricular size and function. The
right ventricle was moderately dilated with preserved sys-
M. Drakopoulou · A. Apostolos · I. Kachrimanidis · G. Oikonomou
· L. Koliastasis · G. Trantalis · C. Tsious · K. Toutouzas (*)
First Department of Cardiology, Medical School, National and
Kapodistrian University of Athens, Hippokration Hospital,
Athens, Greece
tolic function. Color Doppler at the subcostal view revealed
the presence of an atrial septal defect with left to right shunt.
The pulmonary/systemic ow ratio (Qp/Qs) was 2.1:1 based
on ow measurements. The tricuspid valve was competent
and there were no signs of pulmonary hypertension.
Transoesophageal echocardiography (TOE) revealed a
medium-size ostium secundum (18mm) defect with left–toright shunt. The rims were of adequate size for percutaneous
closure (>5mm). All pulmonary veins were in place.
Continued at page 466
Anatomy. The atrial septal defect (ASD) represents an
abnormality in the development of the heart that results in free
communication between the atria [1, 2]. Isolated ASD represents about 7% of all cardiac anomalies and can be present at
any age. There are four major types of defects in the atrial
septum: ostium secundum, ostium primum, sinus venosus,
and unroofed coronary sinus defect [2, 3]. Ostium secundum
ASD is by far the most common type, occurring in 1/1500 live
births. The ostium secundum ASD is a defect that involves the
fossa ovalis region, whereas the other three types are defects
of the endocardial cushions (ostium primum), the junction of
the right atrium, and the superior/inferior vena cava (sinus
venosus) or the coronary sinus (unroofed coronary sinus). It
must be noted that deciencies in the septum primum during
embryologic development may result in a heterogeneous
appearance of secundum ASD, ranging from multiple large
defects to multiple smaller fenestrations or pinpoint defects.
Pathophysiology. Shunting across the interatrial septum
is usually left to right across the ASD and occurs predominantly in late ventricular systole and/or early diastole. Likely,
some augmentation occurs also during atrial contraction.
The magnitude and direction of ow through an ASD depend
on the size of the defect and the relative diastolic lling properties of both left and right ventricles. A reduction or even an
impairment of left ventricular compliance or left heart valve
defects may increase the left-to-right shunt, whereas conditions that reduce right ventricular compliance or the presence
of pulmonary hypertension may cause a right-to-left shunt.
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2024
G. Geroulakos et al. (eds.), Mastering Endovascular Techniques, https://doi.org/10.1007/978-3-031-42735-0_42
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M. Drakopoulou et al.
The chronic left-to-right shunt results in increased pulmonary blood ow and diastolic overload of the right ventricle.
If untreated, chronic signicant left-to-right shunt can alter
the pulmonary vascular resistance leading to pulmonary arterial hypertension (PAH), pulmonary vascular disease, or
even reversal of shunt and Eisenmenger syndrome.
In addition, in the presence of an ASD, a transient and
small right-to-left shunt can occur, especially during periods
of transient increase in right atrial pressure (i.e., during
Valsalva maneuver) even in the absence of pulmonary hypertension. In this case, venous emboli may cross into the left
atrium through the defect and eventually to the systemic circulation, most likely resulting in a paradoxical embolus. The
paradoxical emboli mainly present as cerebral embolic
events or, rather infrequently, as occlusion of coronary, renal,
mesenteric, and peripheral arteries, manifesting as ischemia
and eventual infarction of the affected tissues.
Indications for Closure. Large ASDs should be closed to
reduce the risk of long-term complications; these may
include premature death, atrial arrhythmias, reduced exercise tolerance, hemodynamically signicant tricuspid regurgitation, right ventricular heart failure, and pulmonary
vascular disease and PAH [4]. Current indications for percutaneous or surgical ASD closure range from the relevant signicant left-to-right shunting to the prevention of recurrent
paradoxical embolism [2].
In patients with evidence of right ventricular volume
overload (dened as right ventricular enlargement with
increased stroke volume), no signs of PAH (or pulmonary
vascular resistance, PVR <3 WU in presence of such signs),
and no left ventricular disease, ASD closure is recommended
regardless of symptoms (Class I) [2]. When PVR is ≥3 WU
but remains <5 WU and the Qp:Qs ratio is >1.5:1 there is
also an indication for closure (Class IIa) regardless of symptoms. ASD closure is not recommended in patients with
Eisenmenger physiology, patients with established pulmonary vascular disease (PAH and PVR ≥5 WU despite targeted PAH treatment), or desaturation on exercise [2, 5]. In
patients with signs of left ventricular disease, it is recommended to perform balloon testing and carefully weigh the
benet of eliminating left-to-right shunt against the potential
negative impact of ASD closure on outcome due to an
increase in lling pressure (taking closure, fenestrated closure, and no closure into consideration) [2, 6]. Finally, in
patients with no signs of right ventricular overload, ASD closure is also reasonable in the presence of paradoxical embolism and documented orthodeoxia-platypnea (Class IIa). In
patients with an indication for ASD closure, device closure is
recommended as the method of choice for secundum ASD
closure when anatomically suitable (Class I) [2].
Preprocedural Screening and Transesophageal echocardiography (TOE) Protocol Anatomic suitability for per-
cutaneous ASD closure is determined by TOE [7–10].
Among different types of ASDs, secundum ASD is only suitable for percutaneous closure. TOE evaluation of secundum
defects before closure includes sizing, exploration of the
residual septum’s morphology, evaluation of rim size and
quality, exclusion of additional defects, and conrmation of
a normal pulmonary venous connection.
Secundum ASDs suitable for percutaneous closure are
those with adequate rims (at least 5mm, except for aortic rim
that may be absent) and defect size <40mm. The ASD size
is measured in multiple planes, and color ow and the direction of the shunt are recorded. Rim adequacy and morphology are evaluated in the following three TOE views:
1. Atrioventricular valve rim and posterior superior
rim: four-chamber view (mid-esophageal view, 0°)
(Fig.42.1a)
2. Superior/anterior rim and inferior-posterior rim:
transverse view in the plane of the aortic valve (midesophageal view, 45°) (Fig.42.1b)
3. Superior Vena Cava and Inferior Vena Cava rim: bica-
val view (mid-esophageal view, 90–120°) (Fig.42.1c)
Consideration should be given to the integrity of the rim
tissue. 3D echocardiography provides additional and more
accurate visualization of ASD morphology (Fig.42.2).
Device Selection. Most devices for ASD closure have
similar constructive characteristics (made of metallic framework and polymeric tissue scaffold) and share the same
implantation technique. Beyond the technical consideration
to t within a small sheath, the ideal device should be easily
deliverable, retrievable, and repositionable, biocompatible,
soft, and conformable, able to guarantee an immediate and
complete closure, and with low rates of procedure-related
complications and most importantly with low thrombogenicity [11]. The development of new occlusion devices along
with the improvement of the operator’s experience and
implantation techniques has led to an increase in the implementation of these procedures over the years. The choice of
the device mainly depends on operator experience and preference. The most widely used devices are the Amplatzer
Septal Occluder (Abbot Inc.) and the Gore Cardioform
(W.L.Gore and Associates, Flagstaff, Arizona).
Amplatzer Occluder Device (St. Jude Medical,
Minnesota, USA). The Amplatzer Occluder device is the
most widely used device for ASD closure. It consists of two
discs, the left atrial larger than the right atrial disc, with a
connecting waist, and is fully made of a one-piece Nitinol
mesh lled with Dacron threads [12]. The waist diameter
determines the device size, which requires a 6–8-F sheath
correspondingly. Its function is mainly to keep each disc
tight to the septal wall.
GORE Cardioform Septal Occluder (W. L. Gore &
Associates, USA). The Gore Cardioform Septal Occluder is
ab
42 Atrial Septal Defect: Left Atrial Appendage
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a
LA
RA
RV
Fig. 42.1 Transoeosphageal (TOE) evaluation. (a) Mid-esophageal
4-chamber view at 0°. This view permits localization of the posterior
rim and atrioventricular rim. (b) Mid-esophageal view at 45° with a
leftward (counterclockwise) rotation of the probe to allow simultaneous
LV
Aortic Rim
cb
LA
IVC
visualization of the aortic (anterior) rim and posterior rim. (c) Midesophageal four-chamber view at 90°; the inferior vena cava (IVC) and
the superior vena cava (SVC) rims are seen
SVC
RA
Fig. 42.2 (a, b) 3D transesophageal (TOE) image from a patient with ASD from the right atrial perspective
currently FDA approved for ASD closure [13–15]. The
device is also composed of two discs formed by platinumlled Nitinol wire frames that are covered with an expanded
polytetrauoroethylene lm [16]. The occluder has right and
left atrial discs that form on either side of the atrial septum,
act to close the defect, and hold the occluder in place. It uses
a framework of minimal metal mass to hold a biocompatible
expanded polytetrauoroethylene patch in close apposition
to the septum.
Procedure. Percutaneous ASD is performed either under
moderate sedation or general anesthesia depending on the
mode of procedural imaging guidance. When the procedure
is performed under TOE guidance, general anesthesia is
needed, while when using intracardiac echocardiogram
(ICE), moderate sedation can be used.
Before the procedure, a preoperative antibiotic is administered. After sedating the patient, vascular access is obtained
by the femoral vein (bilateral femoral veins can be used).
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