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Perventricular device closure of
congenital muscular ventricular
septal defects
Expert Rev. Cardiovasc. Ther. 8(5), 663–674 (2010)
Carlos AC Pedra†1,2,
Simone RF Pedra1,2,
Paulo Chaccur1,2,
Marcelo Jatene1,
Rodrigo N Costa1,2,
Ziyad M Hijazi3 and
Zahid Amin3
Instituto Dante Pazzanese de
Cardiologia, Av. Dr Dante Pazzanese
500, 14 andar, CEP 04012-180,
São Paulo, Brazil
2
Hospital do Coração da Associação
Sanatório Sírio, R Desembargador
Eliseu Guilherme, 147, CEP 04004-030,
São Paulo, Brazil
3
Rush Center for Congenital
and Structural Heart Disease,
Rush University Medical Center,
1653, West Congress Parkway,
770 Jones, Chicago, IL 60612, USA
†
Author for correspondence:
Tel.: +55 11 5085 6114
1
Fax: +55 11 5085 6196
[email protected]
www.expert-reviews.com
Muscular ventricular septal defects (MVSDs) account for approximately 20% of all congenital
ventricular septal defects. Large defects in infants result in early heart failure, failure to thrive
and pulmonary hypertension. Although percutaneous closure of MVSDs has been employed
safely and effectively in children, adolescents and adults, its application in the small infant
(weight <6 kg) carries a higher risk for complications including arrhythmias, hemodynamic
compromise, cardiac perforation, tamponade and death. Perventricular closure of such defects,
introduced by Amin and coworkers in the late 1990s, has become an attractive treatment
modality for these small and high-risk patients. Experience worldwide has shown that the
procedure is feasible, reproducible, safe and effective. In this article, the authors review the
indications, the step-by-step technique and the results of perventricular closure of MVSDs using
the AMPLATZER® mVSD device (AGA Medical, MN, USA).
Keywords : AMPLATZER • hybrid • interventional catheterization • muscular ventricular septal defects
• perventricular
Muscular ventricular septal defects (MVSDs)
account for approximately 20% of all congenital
ventricular septal defects (VSDs) [1,2] . By definition, all rims of a MVSD are surrounded by muscular tissue within the interventricular septum
(IVS) [1,2] . They can be located in the trabecular,
apical or anterior region of the IVS [1,2] , and are
usually distant from the atrioventricular node.
When the defect is restrictive, the natural history usually shows spontaneous closure in most
patients within the first 4–5 years of life [1,2] .
Treatment is indicated when the defect results in
heart failure in infancy or when there is volume
overload of the left ventricle (LV) on echocardiography [1,2] . Worldwide experience has shown that
percutaneous treatment of such defects is feasible,
resulting in excellent outcomes in most patients
from infancy to adulthood [3–12] . Complications
are uncommon beyond infancy but may include
embolization in an occasional adult patient in
whom the septum might be too thick to accommodate the AMPLATZER® congenital mVSD
device (AGA Medical, MN, USA) [13] . In addition, the application of this technique in the
small infant (weight <5–6 kg) is associated with
a higher risk for complications including hemodynamic compromise, arrhythmias, cardiac perforation, tamponade and death [5,10] . The concept
10.1586/ERC.10.31
of intraoperative closure of VSDs via a perventricular approach was introduced by Amin and
coworkers in the late 1990s [14] . In this procedure,
after a standard median sternotomy is performed
by the surgical team, a delivery sheath is advanced
through the anterior wall of the right ventricle
(RV) across the defect into the LV. Under transesophageal echocardiographic (TEE) guidance,
an intracardiac device is implanted through the
delivery sheath by the interventionalist. Further
publications documented its feasibility, reproducibility, safety and efficacy in this high-risk
age group [15–21] . In this report, the authors will
discuss the indications, the step-by-step technique and the results of ­perventricular closure
of MVSDs.
Anatomical classification of MVSDs for
the interventionalist
For the sake of ease and simplicity, the authors
will describe a classification that is thought to
be useful for the interventionalist. The IVS is a
complex structure assuming an S-shape, separating the atrioventricular and semilunar valves.
The muscular septum comprises most of the IVS
and can be divided into three regions according
to its right ventricular aspect (Figure 1) : trabecular,
apical and anterior outlet septum. A trabecular
© 2010 Expert Reviews Ltd
ISSN 1477-9072
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Pedra, Pedra, Chaccur et al.
MVSD can extend into the inlet portion of the muscular IVS.
This form is also called by some an inlet MVSD and should
be differentiated from the true atrioventricular septal defect [22] .
Apical defects are those located near the apex. The anterior outlet
defects are the most uncommon and owing to their location, they
can be challenging to cross with a guide wire using a perventricular approach. Most of the MVSDs are single and isolated lesions
located in the mid portion of the trabecular IVS, the so-called
mid-MVSDs. Sometimes the IVS looks like a sieve and has multiple muscular openings both in the left and right sides of the IVS.
These defects are termed ‘Swiss cheese’ defects and may require
multiple devices and repeat procedures for closure. Nevertheless,
residual leaks are commonly seen after these multiple attempts.
Indications of perventricular closure of MVSDs
Perventricular closure is an alternative way of closing MVSDs
using cardiac catheterization, echocardiographic and surgical
techniques [22] . As such, this kind of hybrid procedure should
SVC
A
P
R
1
5
C
NC
M2
V
3
4
6
only be applied in special clinical scenarios. It is mainly indicated
for the small infant weighing less than 5–6 kg with large and
unrestrictive MVSDs, suffering from significant heart failure,
pulmonary hypertension and failure to thrive [15–22] . In short,
these patients are too fragile and not stable enough to undergo a
long cardiac catheterization procedure. Vascular issues may also
be a limiting factor. In addition, it has been shown that infants
weighing less than 5–6 kg are at risk for complications during
percutaneous closure of the MVSD [5,10] . On the other hand, one
may consider undertaking the perventricular approach in infants
a little bit larger than the threshold suggested earlier given the
simplicity of perventricular closure and variations in policies at
different institutions [21] .
The patient with a hemodynamically significant MVSD associated with a concomitant condition that requires surgical repair,
such as coarctation of the aorta, double-outlet RV, transposition
of the great arteries and status post-pulmonary artery banding,
may also benefit from the perventricular procedure [15–22] . In these
patients, the MVSD can be closed using a
perventricular approach through a median
sternotomy and the associated defect can
be surgically repaired at the same session
in the operating room (OR). Avoidance
of cardiopulmonary bypass (CPB) or limiting its time is a major advantage of the
hybrid approach resulting in less morbidity,
both in the short and long term, and faster
­recovery [23–29] .
The patient with a small and restrictive MVSD, thriving well and without
heart failure, should not undergo a per­
ventricular procedure. Spontaneous closure
of such defects has been reported in most
cases, usually in the first 5 years of life [1,2] .
Closure of these defects with catheter, surgical or hybrid techniques on the basis of
endocarditis prevention is highly debatable
and not widely accepted [1,2] .
MVSD devices
IVC
Figure 1. The interventricular septum from the right ventricular perspective.
Encircled are the main locations of the muscular ventricular defects: (4) represents the
trabecular mid-muscular defect; (6) represents the apical defects and (5) represents
the anterior outlet defects. (1) represents the doubly committed or juxta arterial
ventricular septal defects; (2) represents the perimembranous defect and (3) the inlet
or atrioventricular type of ventricular septal defect.
A: Aorta; C: Conal septum; IVC: Inferior vena cava; NC: Non-coronary cusp; P: Pulmonary
trunk; R: Origin of the right coronary artery; SVC: Superior vena cava; V: Region of the
AV node.
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There are three devices available for MVSD
closure: the CardioSEAL® (Nitinol Medical
Technology, MA, USA), the Nit-Occlud®
(Products fur Medizine, Germany) and the
AMPLATZER mVSD. Because most, if
not all, of the experience on perventricular closure of MVSDs was built using the
AMPLATZER mVSD device and the
authors are not familiar with the first two
devices used in a perventricular approach,
we will focus on this occluder. The
AMPLATZER mVSD device (Figure 2) was
designed specifically for closure of MVSDs.
Of note, this device is approved for clinical
use by the US FDA and by the Brazilian
Expert Rev. Cardiovasc. Ther. 8(5), (2010)
Perventricular device closure of congenital muscular ventricular septal defects
National Health Vigilance Agency. It is made of a self-expanding
Nitinol wire mesh woven into two discs connected by a 7-mm long
cylindrical waist. Reinforced layers of polyester patches are sewn
into the internal part of the Nitinol wire mesh to increase its occlusion rates. The device is malleable and has a shape memory owing
to the properties of Nitinol. The size of the device is based on the
diameter of the waist, which ranges from 4 to 18 mm in 2-mm
increments. The discs are 8 mm larger than the connecting waist,
except for the 4-mm device, in which the discs are 5 mm larger
than the waist. Owing to the 7-mm separation between the two
discs, the device seats well within the muscular defect, adjusted to
the thickness and the motion of the IVS. As it happens with other
AMPLATZER devices, the connecting waist has a stent-like effect
on the edges of the defect and provides a self-centering mechanism,
which helps to avoid prolapses during implantation and enhances
closure rates. The device connects to the delivery cable by a female
microscrew, located in the central portion of the right ventricular
disc. The size of the delivery sheath required for implantation
depends on the size of the device, ranging from 6–9 F.
Because most MVSDs are oval in shape, a device that is approximately 2 mm larger than the largest end-diastolic diameter of the
MVSD measured in at least two orthogonal echocardiographic
views is selected for implantation [22] . Patients with severe pulmonary hypertension and/or with a deficient posteroinferior rim
at the crux cordis may need some more oversizing (>3 mm than
the largest diameter) to avoid prolapse and/or embolization [21] .
The perventricular procedure
Perventricular closure of MVSDs can be performed either in the
OR (more common) or in a hybrid catheterization suite, if available. Regardless of the location chosen, it is crucial to have an
experienced echocardiographer to monitor all steps of the procedure. A deep knowledge of the IVS anatomy, wire and catheter
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Figure 2. The AMPLATZER® (AGA Medical, MN, USA)
muscular ventricular septal defects device. The device is
made of a nitinol wire mesh forming two discs of the same size
connected by a waist.
manipulations, device delivery and deployment, and postrelease
interrogation are all critical for procedural success and can only
be accomplished by an experienced interventional echocardiographer. One must remember that in the operating room, the only
imaging tool available to guide the whole procedure is the TEE.
In less than ideal circumstances, epicardial echocardiography has
also been used with good results.
The procedure is performed under endotracheal general anesthesia. The size, location, proximity of valvular structures and
number of defects are evaluated by TEE. After a median mini
Figure 3. Median sternotomy and identification of the proper site to place the purse string suture. After median sternotomy is
performed and the heart is secured in position in a pericardial cradle, surgical instruments (A) or the index finger (B) are used to gently
push the right ventricular anterior free wall in order to identify the best location for placement of the purse string suture. The bulging on
the anterior right ventricular free wall and its relation to the interventricular septum and the muscular ventricular septal defect are defined
by transesophageal echocardiogram.
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Pedra, Pedra, Chaccur et al.
Figure 4. Transeophageal echocardiographic monitoring during perventricular closure of the muscular ventricular septal
defect. Four-chamber view. (A) Single muscular ventricular septal defect located in the mid-trabecular area of the septum measuring
9–10 mm. (B) The distance between the anterior right ventricular free wall and the posterior left ventricular wall is measured (35 mm).
(C) Internal bulging of the anterior right ventricular free wall after it is gently pushed using the index finger. (D) A J-tip 0.038-inch
echogenic guide wire is seen across the defect into the left ventricle.
or standard sternotomy is performed, the heart is secured in a
pericardial cradle. Heparin sulfate is given (100 IU/kg) and
prophylactic antibiotics are used according to local protocols.
Under TEE guidance, the best location for needle puncture
and sheath entry through the free wall of the RV is identified
(F igures 3 & 4) . This is accomplished by gently pushing the anterior free wall of the RV using the index finger just opposite to
the MVSD location, keeping a straight line and a perpendicular
angle to the IVS (Figures 3 & 4) . A purse string suture is placed on
this site. A 17–20-gauge needle (angiocath or metal) is inserted
through the purse string suture into the RV cavity (Figure 5) . A
Terumo glide wire or, preferably, a regular 0.038-inch J-tip wire
(available in the standard short sheath box set) is maneuvered
across the MVSD into the LV (Figures 4 & 5) . The regular J-tip
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wire is usually easier to track by TEE since it is more echogenic
than the Terumo wire. In addition, it rarely passes across the
trabeculation of the RV owing to its J-tip. Once the wire is
identified in the LV cavity, the needle is removed leaving sufficient amounts of wire in the LV. Some advocate predilating the
RV free wall using a dilator that is 1 F larger than the sheath
that is being planned to be used for deployment, although this
is not mandatory [22] . In order to avoid inadvertent trauma to
the posterior LV wall, the selected standard short sheath is premarked using a cotton suture (Figure 6) . The distances between
the anterior RV wall and the free LV cavity and the posterior
LV wall are measured by TEE using the four-chamber view
(F igure 4) . The distance between the free cavity of the LV (where
the tip of the sheath should be positioned) and the anterior RV
Expert Rev. Cardiovasc. Ther. 8(5), (2010)
Perventricular device closure of congenital muscular ventricular septal defects
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Figure 5. Purse string suture and puncture of the right ventricular free wall. (A) A purse string suture is placed on the right
ventricular free wall by the surgeon. (B) A metallic needle is inserted through the right ventricular wall and a J-tip guide wire is advanced
through the needle across the ventricular septal defect.
wall (where the suture should be secured on the sheath) is then
used as a reference for marking the sheath. The appropriate
sized and marked short sheath is then advanced over the wire
into the LV. A useful tip is to slide the sheath over the dilator
and the guide wire once the dilator is approximately 1–2 cm
past the anterior wall of the RV. Even premarking the delivery
sheath, it is crucial to recognize the tip of the dilator and the
sheath on TEE to prevent injuries to the posterior wall of the
LV (Figure 7) . Flushing the sheath with saline is also helpful to
verify where it is. An appropriate sized device is loaded either in
the standard plastic loader that is enclosed in the delivery system
package or in another short sheath with the same profile as the
one left across the MVSD. The loader or the loading sheath is
advanced through the hemostatic valve of the short sheath positioned across the MVSD and the delivery cable is pushed gently
(F igure 6) . In order to ensure a smooth transition of the device
from the loader to the short sheath, it is helpful to have a second
pair of hands securing the short sheath in place in the RV wall.
Once the device is transferred to the short sheath, the loader is
removed. Under TEE guidance and in the beating heart, the
delivery cable is slowly advanced in order to deploy the LV disc
in the middle of the LV free cavity. TEE pictures must leave
no doubts with regards to the location of the LV disc. It should
be clearly seen inside the free LV cavity (Figure 7) . Special attention must be taken to ensure that there is no entanglement
within the mitral valve apparatus. A slow and gentle pull on
the short sheath exposes the connecting waist (Figure 7) . After
this is confirmed by TEE, the whole system is brought back as
a unit until the waist is seen within the MVSD itself and the
LV disc is seen abutting the IVS on the left side (Figure 7) . The
right disc is then delivered by very slowly and gently pulling
back the sheath and advancing the delivery cable (two-hand
Figure 6. Sheath positioning across the right ventricular free wall. (A) An 8 F standard short sheath is positioned through the right
ventricular free wall. Note the suture on the sheath abutting the right ventricular wall. (B) After the device is transferred from the loader
to the short sheath, implantation is performed with gentle movements, pulling on the sheath and pushing on the delivery cable.
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Pedra, Pedra, Chaccur et al.
Figure 7. Transeophageal echocardiographic monitoring during implantation. Four-chamber view. (A) The short 8 F sheath is
seen across the defect. The tip is located in the mid-left ventricular cavity, away from the posterior wall. (B) The left disc and the waist of
a 12‑mm device are deployed in the mid-left ventricular cavity. (C) The left disc is approaching the interventricular septum. (D) Adequate
device positioning within the septum.
technique). This delicate maneuver is of paramount importance
since there is not much room in the RV to deploy the RV disc.
Device position, possible interference with the function of the
atrioventricular and semilunar valves, and residual leaks are
then assessed by TEE (Figure 7) . Once the operators are sure that
the device seats properly within the IVS with no impingement
on any important cardiac structure, the device is released by
rotating the delivery cable in a counterclockwise fashion. After
device release, the delivery cable is withdrawn followed by the
short delivery sheath. The purse string suture is tied, heparin
is partially neutralized using protamine sulfate based on the
activated coagulation time results and the chest is closed in a
standard fashion. Pericardial drains, chest tubes and epicardial
leads are not commonly left in place after a straightforward
­procedure to close an isolated MVSD.
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In the case of an associated coarctation
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of the aorta����������
or a previously placed pulmonary artery banding, the lesions are subsequently repaired without the need of CPB. In the case of a
complex congenital heart disease with unusual orientation of the
IVS such as double-outlet RV or transposition of great arteries
with an additional MVSD, the underlying condition is repaired
surgically after the MVSD is device closed with this technique,
sparing some precious time of CPB.
Troubleshooting: adjusting & customizing
the technique
For apical defects, it is easier to cross the defect from a purse string
suture placed near the apex. However, using this approach it may
be more difficult (or even impossible) to deploy the right disc
inside the right ventricular cavity owing to lack of space. In this
Expert Rev. Cardiovasc. Ther. 8(5), (2010)
Perventricular device closure of congenital muscular ventricular septal defects
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case, the right disc must be deployed very
slowly (over 30 s) so as to give it ample time
to reconfigure its shape as close to the IVS
as possible [22] . If this does not work and
the female end of the microscrew and part
of the right disc protrudes out of the apical
RV free wall, this part of the device should
be secured to the RV wall using standard
stitches and sutures (Figure 8) . Although this
may not seem cosmetically adequate, it has
not caused any clinical problems thus far.
An AMPLATZER Duct Occluder (AGA
Medical), with no disc on the right side
may also be used in this setting. Another
option to deal with apical defects is to place
the purse string suture not at the apex but
towards the mid portion of the anterior free
wall of the RV [22] . One can use a bent needle to cross the defect, and a curved braided
short sheath and dilator to reach the LV. The
sheath is advanced through the RV free wall
at an angle as if the defect was being closed Figure 8. The female microscrew and part of the right disc is seen protruding out
from the internal jugular vein. Maneuvers to of the apical right ventricular wall. The device was secured in place using standard
avoid device prolapse towards the RV while stitches and suture material. The delivery cable is still attached to the microscrew.
deploying the device should be taken using
this approach.
out from the short sheath positioned in the free RV wall. Over
We have not encountered a case in which a mid-muscular this wire, the delivery sheath is advanced and the procedure
or an apical defect could not be crossed with a guide wire [22] . completed [30] .
Occasionally, it may be difficult to cross an anterior defect comFor extremely large defects (>14 mm), especially when there is
ing from the RV free wall. In such cases, a ‘true’ hybrid approach a deficient posteroinferior rim towards the crux cordis (Figure 9)
may be employed to deal with the problem [30] . With the aid of and associated pulmonary hypertension, it may be necessary to
angiography and fluoroscopy in a hybrid suite or using a portable oversize the device a little more than 2 mm in order to avoid
C-arm in the OR, a catheter is positioned percutaneously in the device prolapse or embolization. Another option is to secure the
LV and the defect is crossed retrogradely with a guide wire. The device in place by placing a stitch through the RV wall catching
wire is then snared in the pulmonary artery and exteriorized the edge of the deployed RV disc (Figure 10) [21] .
Figure 9. Transesophageal echocardiography in a modified gastric view. (A) Large mid-muscular ventricular septal defect
with apical extension and a deficient posteroinferior rim. (B) Large (15-mm) muscular ventricular septal defect located in the
mid-to-apical portion of the interventricular septum in a 2-year-old female patient previously submitted to pulmonary artery banding.
The postero‑inferior rim of the defect is deficient.
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Pedra, Pedra, Chaccur et al.
Figure 10. Transesophageal echocardiography in a modified gastric view (same patient as in Figure 9 ). (A) Prolapse of the
inferior portion of the left disc of a 16 mm device through the deficient part of the septum. (B) After the sheath was slightly reoriented,
the device was correctly deployed and subsequently secured in place with stitches placed across the right ventricular wall catching the
edge of the right ventricular disc. Color Doppler interrogation shows complete occlusion and no interference with the atrioventricular
valve function.
In the case of multiple defects, each defect is approached in
a standard fashion using the previously described techniques. It
may be wiser to start closing the more apical defect first to leave
more room to deploy a second or even a third device higher up
in the middle of the RV cavity.
Because the sheath usually crosses the VSD in a perpendicular
fashion, it is uncommon to pull the device through the defect
using the perventricular approach. If the device is undersized,
it obviously needs to be replaced. Deploying the waist in the LV
cavity helps to align the LV disc to the plane of the LV septum,
preventing the edge of the disc from protruding into the defect
[22] . If the defect is large and the posteroinferior rim at the crux
cordis is somewhat deficient (Figures 9 & 10) , one may need to slightly
change the orientation of the sheath in order to bring the device
in a more parallel fashion towards the IVS. Securing the device
in place with a suture as described previously may also be helpful
in such cases.
Entanglement of the left disc within the mitral valve apparatus
may occur during the procedure. It should be avoided by deploying
the LV disc closer to the IVS and performing meticulous TEE. If
there is any difficulty bringing the left disc and the delivery sheath
back towards the IVS and the LV disc does seem to be entangled
within the mitral valve apparatus on TEE, one should carefully
advance the sheath and the device deep in the LV and recapture the
LV disc [22] . Sometimes, both discs have to be deployed in the LV
to untangle the device from the mitral valve chordae [22] . If these
maneuvers do not work, surgical removal should be undertaken
to prevent damage to the mitral valve apparatus.
Figure 11. Chest radiograph pre- and postprocedure. (A) Enlarged cardiac silhouette and increased pulmonary vascular markings
are conspicuous. (B) On the first postoperative day there was a remarkable decrease in the size of the heart and improvement in the lung
fields. The implanted device is seen in the left lower portion of the cardiac silhouette.
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Expert Rev. Cardiovasc. Ther. 8(5), (2010)
Embolization is a rare event using a perventricular approach.
It is probably associated with inadequate device selection and/or
unrecognized device malposition prior to release. The operators must identify where the embolized device is stuck. Because
patients undergoing perventricular closure of MVSDs are small,
device retrieval using percutaneous or perventricular techniques
are usually not feasible and may carry a higher risk than expected.
Surgical retrieval of the device followed by patch closure of the
MVSD should generally be undertaken.
In the rare event of failure to close the defect using a perventricular approach, the patient can still undergo standard surgical
patch closure of the MVSD under CPB or have a band placed
around the main pulmonary artery.
Follow-up
The patient is usually extubated in the first hours after the
procedure and is routinely monitored in the intensive care unit
for 24–48 h. Inotropic support is rarely required. A transthoracic echocardiogram is performed the following day to
assess device position, residual leaks and pericardial effusion.
Patients are typically discharged 3–7 days after an uneventful procedure with remarkable improvement in their clinical
conditions (Figure 11) . Aspirin is usually given a couple of days
prior to the procedure (3–5 mg/kg/day) and maintained for
6 months. Bacterial endocarditis prophylaxis is recommended
for 6 months or indefinitely if there is residual shunting persisting for over 1–2 years. Clinical visits and serial transthoracic
echocardiograms are scheduled for 1, 3, 6 and 12 months after
the procedure and yearly after. Although debatable, repeat
Holter monitoring is advocated by some in order to detect
­subclinical conduction abnormalities.
Results
Because large MVSDs in small infants are not commonly encountered in clinical practice, most of the experiences of perventricular
closure of such defects reported in the literature are based on
small cohorts of patients [15–21] . As such, it seems prudent for
low-volume institutions to refer these cases to institutions that are
better versed with this procedure [22] . Even being a relatively new
and uncommon procedure, with information based on a limited
number of patients in the literature, the perventricular closure of
MVSDs seems to be feasible and ­reproducible in different hands,
safe and highly effective.
The technical success rate of the perventricular approach should
approach 100% in the hands of interventional and surgical teams
experienced in treating congenital heart diseases. Complication
rates should decrease with accumulation of experience [22] . The
risk of device embolization should be minimized by state-ofthe-art use of TEE techniques and optimal device selection and
positioning. Cardiac perforation should be avoided by careful
and meticulous technique. Blood loss requiring transfusion may
be an issue in these small and already fragile patients. Pericardial
effusion and tamponade may occur, usually due to catheter injury
of the LV posterior free wall, which is minimized with judicious
techniques. It is speculated that late LV aneurysm formation may
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Figure 12. Echocardiographic views of a large mid-muscular ventricular septal defect with apical extension and a deficient posteroinferior rim. (A) Modified fourchamber view on transesophageal echocardiography before device implantation showing a large (14–15‑mm) defect. (B) Same modified four-chamber view on transesophageal
echocardiography immediately after device implantation. A 16‑mm device is in good position with no prolapse towards the right ventricle. (C) Subxiphoid view on a transthoracic
echocardiogram performed 1 week after implantation showing prolapse of the left posteroinferior portion of the device towards the right ventricle (arrow).
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be due to injury in the posterior LV wall during the procedure [31] .
Interference with the function of the atrioventricular valves is
uncommon but may occur when the trabecular defect extends
towards the inlet septum. Interference with the function of the
semilunar valves has not been described. Device-related hemolysis is rare and only occurs when a high-velocity residual leak is
encountered at the edge of the device. Conservative management
over a couple of days may be sufficient to treat this complication.
Some advocate soaking the device in the patient’s own blood to
enhance the immediate occlusion rate and prevent hemolysis [22] .
Conduction abnormalities are relatively uncommon. A right or a
left bundle branch block pattern may occasionally be encountered
but usually has a benign course [32] . Complete heart block is rare
and should prompt device removal when it occurs within the first
hours or days after implantation. It is possible that the inlet type
of muscular defect is at a higher risk for this complication [21] .
Late heart block has not been described. The risk of death should
be related to the patient’s comorbid ­condition rather than to the
procedure itself.
Closure rates are high. For the isolated and single MVSD,
occlusion rates should approach 100% [15–21] . Residual leaks may
be seen in multiple defects in which multiple devices have been
used. However, most of these leaks are small and do not require
further interventions, especially when the indexed left ventricular
end-diastolic dimension for body surface area returns to normal
(or near normal) values.
In a multicenter experience in South America, from July 2007
to May 2009, nine non-consecutive patients (median age and
weight 6 months and 5.5 kg, respectively) underwent the procedure in the OR under TEE guidance using AMPLATZER
devices [21] . All patients but one were in congestive heart failure
and had pulmonary arterial hypertension. One patient was status
post-pulmonary artery banding and three also had coarctation
of the aorta, which were all repaired at the same session. Eight
patients had single MVSDs (six mid-muscular, two apical) measuring 10.3 ± 3.7 mm and one patient had multiple apical defects
that required two devices. Ten devices were implanted successfully (median size: 12 mm), with two having to be secured in the
RV wall with a surgical suture. One patient each developed right
and left bundle branch block. In one patient with a 14-mm defect,
the inferior portion of a 16-mm device prolapsed through the
posteroinferior rim of the defect towards the RV (Figure 12) , requiring surgical removal with patch closure of the mid-MVSD. In
retrospect, a larger device or fixation in the right ventricular wall
should have been employed to avoid prolapse in this case. After a
median follow-up of 1 year, all eight remaining patients, including
the one with two devices, had complete closure of the defects with
normal LV. The authors went on to conclude that perventricular
closure of MVSDs seemed to be reproducible, feasible, relatively
safe and effective in their hands. However, large defects may need
device oversizing or suture fixation for adequate stabilization.
In the largest personal experience encountered, Amin has performed 54 cases with a technical success rate of initial device
implantation of 100% [Pedra CAC, Pers. Comm.] . However, some
failures and complications were observed. In one patient with
two defects, the second defect could not be crossed after one
device had already been placed. One patient developed complete
heart block within a few hours of the procedure and required a
pacemaker. This patient had a high inlet MVSD. One patient
had device embolization to the LV requiring surgical removal.
This patient had prolonged PA banding with severe RV hypertrophy and pulmonary hypertension. We believe that the defect
measurement was inadequate and underestimated at the time of
the procedure. The VSD size increased as the RV hyper­trophy
regressed. One patient had elective device removal owing to
hemolysis 5 days after the procedure. The remainder of the
patients have had a follow-up ranging from 4 months to 10 years
with excellent results.
Expert commentary
Device closure of MVSDs has significantly evolved over the
last years and perventricular closure of MVSDs has emerged
as the modality of choice to manage the small infant with a
large defect. It enables a direct route to close the defect, minimizing the chances of hemodynamic compromise that usually
occurs with the percutaneous technique in the catheterization
laboratory. Because it avoids CPB, the morbidity is limited and
recovery time is optimized. In addition, it is associated with
high occlusion rates and consistent outcomes that persist in the
mid-term follow-up.
Key issues
• Large muscular ventricular septal defects (MVSDs) can result in heart failure, pulmonary hypertension and failure to thrive in
small infants.
• Surgical closure of such defects can be challenging owing to the heavily trabeculated right ventricle and may be associated with
significant morbidity, including residual shunting and the adverse effects of cardiopulmonary bypass.
• Percutaneous closure of MVSDs can be performed safely and effectively in children and adolescents. In adults, there might be a slightly
higher risk of embolization owing to the thickness of the interventricular septum. However, small infants (weight <5–6 kg) are at a
higher risk for severe complications including hemodynamic compromise, arrhythmias, cardiac perforation, tamponade and death, and
remain a challenging subset of patients.
• Perventricular device closure of the MVSD in the beating heart has emerged as an excellent alternative to manage such fragile and
high-risk patients. Clinical experience, albeit still limited, has demonstrated that the procedure is feasible and reproducible in different
hands, safe and highly effective.
• Further refinements in the technique are likely to improve the overall results, further decreasing an already remarkably low
morbidity rate.
672
Expert Rev. Cardiovasc. Ther. 8(5), (2010)
Perventricular device closure of congenital muscular ventricular septal defects
Five-year view
Miniaturized probes to perform real-time 3D TEE will probably
be available in the near future. This might contribute to a better
understanding of the anatomy of the IVS, the multiple defects
and those that are large with a deficient posteroinferior rim at
the crux cordis. A shorter, curved and braided AMPLATZER
TorqVue ® (AGA Medical) delivery sheath, and a shorter and
more flexible delivery cable (with Nitinol extension at the distal
extremity) will probably be used for perventricular device closure
of large MVSDs in small infants in the near future. Limiting
(or even eliminating?) surgical scar and the extension of the
median sternotomy will also be part of the next challenges to
References
7
Papers of special note have been highlighted as:
• of interest
•• of considerable interest
1
2
3
4
5
6
Tynan M, Anderson RH. Ventricular
septal defect. In: Paediatric Cardiology.
Anderson RH, Baker EJ,
Macartney FJ, Rigby ML,
Shinebourne EA, Tynan M (Eds).
Churchill Livingstone, London, UK,
983–1014 (2002).
Kouchoukos NT, Blackstone EH,
Doty DB, Hanley FL, Karp RB.
Ventricular septal defect. In: Kirklin/
Barratt-Boyes Cardiac Surgery. Kouchoukos
NT, Blackstone EH, Doty DB, Hanley FL,
Karp RB (Eds). Churchill Livingstone,
PA, USA, 850–910 (2003).
Thanopoulos BD, Tsaousis GS,
Konstadopoulou GN, Zarayelyan AG.
Transcatheter closure of muscular
ventricular septal defects with the
AMPLATZER ventricular septal defect
occluder: initial clinical applications in
children. J. Am. Coll. Cardiol. 33(5),
1395–1399 (1999).
Hijazi ZM, Hakim F, Al-Fadley F,
Abdelhamid J, Cao QL. Transcatheter
closure of single muscular ventricular septal
defects using the AMPLATZER muscular
VSD occluder: initial results and technical
considerations. Catheter. Cardiovasc. Interv.
49(2), 167–172 (2000).
Holzer R, Balzer D, Cao QL, Lock K,
Hijazi ZM. Device closure of muscular
ventricular septal defects using the
AMPLATZER muscular ventricular septal
defect occluder: immediate and mid-term
results of a U.S. registry. J. Am. Coll.
Cardiol. 43(7), 1257–1263 (2004).
Arora R, Trehan V, Thakur AK, Mehta V,
Sengupta PP, Nigam M. Transcatheter
closure of congenital muscular ventricular
septal defect. J. Interv. Cardiol. 17(2),
109–115 (2004).
www.expert-reviews.com
8
9
improve the overall results of the procedure in the upcoming
years. Reabsorbable devices will not be part of ­clinical practice
in the next 5 years but might be in the next decade.
Financial & competing interests disclosure
Carlos AC Pedra and Zahid Amin are consultants and on the speakers’
bureau for AGA Medical (MN, USA). The authors have no other relevant
affiliations or financial involvement with any organization or entity with
a financial interest in or financial conflict with the subject matter or
­materials discussed in the manuscript apart from those disclosed.
No writing assistance was utilized in the production of this
manuscript.
Thanopoulos BD, Rigby ML. Outcome
of transcatheter closure of muscular
ventricular septal defects with the
AMPLATZER ventricular septal defect
occluder. Heart 91(4), 513–516 (2005).
Carminati M, Butera G, Chessa M, Drago
M, Negura D, Piazza L. Transcatheter
closure of congenital ventricular septal
defect with AMPLATZER septal
occluders. Am. J. Cardiol. 96, 52L–58L
(2005).
Djer MM, Latiff HA, Alwi M, Samion H,
Kandavello G. Transcatheter closure of
muscular ventricular septal defect using the
AMPLATZER devices. Heart Lung Circ.
15(1), 12–17 (2006).
10
Diab KA, Cao QL, Mora BN, Hijazi ZM.
Device closure of muscular ventricular
septal defects in infants less than one
year of age using the AMPLATZER
devices: feasibility and outcome.
Catheter. Cardiovasc. Interv. 70(1), 90–97
(2007).
11
Queiroz FJ, Rossi Filho RI, Ramos S et al.
Percutaneous occlusion of interventricular
septal defects. Initial experiment. Arq. Bras.
Cardiol. 85(3), 174–179 (2005).
12
Pedra CAC, Pedra SRF, Pessotti C et al.
Percutaneous closure of congenital
muscular ventricular septal defects.
Rev. Bras. Cardiol. Inv. 16(2), 218–224
(2008).
13
Bialkowski J, Szkutnik M, Kusa J, Fiszer R.
Few comments regarding transcatheter
closure of congenital perimembranous
and muscular ventricular septal defects.
Int. J. Cardiol. DOI: 10.1016/j.
ijcard.2009.04.029 (2009) (Epub ahead
of print).
14
Review
Amin Z, Berry JM, Foker JE, Rocchini AP,
Bass JL. Intraoperative closure of muscular
ventricular septal defect in a canine model
and application of the technique in a baby.
J. Thorac. Cardiovasc. Surg. 115, 1374–1376
(1998).
•• First paper to report the concept of
perventricular device implantation.
15
Bacha EA, Cao QL, Starr JP, Waight D,
Ebeid MR, Hijazi ZM. Perventricular
device closure of muscular ventricular
septal defects on the beating heart:
technique and results. J. Thorac.
Cardiovasc. Surg. 126, 1718–1723 (2003).
16
Bacha EA, Cao QL, Galantowicz ME et al.
Multicenter experience with perventricular
device closure of muscular ventricular
septal defects. Pediatr. Cardiol. 26(2),
169–175 (2005).
•• First multicenter study reporting
consistent results of perventricular closure
of muscular ventricular septal defects.
17
Gan C, Lin K, An Q et al. Perventricular
device closure of muscular ventricular
septal defects on beating hearts: initial
experience in eight children. J. Thorac.
Cardiovasc. Surg. 137(4), 929–933
(2009).
•
Results of a center in China confirming
the reproducibility of the method.
18
Crossland DS, Wilkinson JL, Cochrane
AD, d’Udekem Y, Brizard CP, Lane GK.
Initial results of primary device closure of
large muscular ventricular septal defects in
early infancy using perventricular access.
Catheter. Cardiovasc. Interv. 72(3),
386–391 (2008).
•
Results of a center in Australia confirming
the reproducibility of the method.
19
Celiker A, Ozkutlu S, Erdoğan I,
Karagöz T, Doğan OF, Demircin M.
Perventricular closure of muscular
ventricular septal defect in an infant.
Anadolu. Kardiyol. Derg. 8(4), 312–313
(2008).
20
Becker P, Frangini P, Heusser F, Urcelay G,
Garay F. New surgical approach to device
closure of multiple apical ventricular septal
defects. Rev. Esp. Cardiol. 57(12),
1238–1240 (2004).
673
Review
21
•
22
Pedra, Pedra, Chaccur et al.
Pedra CAC, Pedra SRF, Chaccur P et al.
Perventricular closure of congenital
muscular ventricular septal defect:
multicenter experience in South America.
Rev. Bras. Cardiol. Invs. 17(3), 386–397
(2009).
Results of a multicenter study in South
America confirming the reproducibility of
the method.
Interesting review on percutaneous and
perventricular closure of muscular
ventricular septal defects.
23
Serraf A, Lacour-Gayet F, Bruniaux J et al.
Surgical management of isolated multiple
ventricular septal defects. Logical approach
in 130 patients. J. Thorac. Cardiovasc. Surg.
103, 437–442 (1992).
Kitagawa T, Durham LA III, Mosca
RS, Bove EL. Techniques and results
in the management of multiple
674
29
Hovels-Gurish HH, Konrad K,
Skorzenski D et al. Long-term behavior
and quality of life after corrective
cardiac surgery in infancy for tetralogy
of fallot or ventricular septal defect.
Pediatr. Cardiol. 28(5), 346–354
(2007).
25
Hanna B, Colan SD, Bridges ND,
Mayer JE, Castaneda AR. Clinical and
myocardial status after left ventriculotomy
for ventricular septal defect closure. J. Am.
Coll. Cardiol. 17(Suppl.), 110A (1991).
30
26
Wollenek G, Wyse R, Sullivan I, Elliot M,
de Leval M, Stark J. Closure of muscular
septal defects through a left ventriculotomy.
Eur. J. Cardiothorac. Surg. 10, 595–598
(1996).
Diab KA, Hijazi ZM, Cao QL, Bacha EA.
A truly hybrid approach to perventricular
closure of multiple muscular ventricular
septal defects. J. Thorac. Cardiovasc. Surg.
130(3), 892–893 (2005).
31
27
Kaltman JR, Javik GP, Bernabaum J et al.
Neurodevelopmental outcome after early
repair of a ventricular septal defect with
or without aortic arch obstruction.
J. Thorac. Cardiovasc. Surg. 131(4),
792–798 (2006).
Breinholt JP, Rodefeld MD, Hoyer MH.
Successful embolization of a left ventricular
pseudoaneurysm after perventricular
ventricular septal defect device closure.
Catheter. Cardiovasc. Interv. 74(4),
624–626 (2009).
32
28
Hovels-Gurish HH, Konrad K,
Skorzenski D, Herpertz-Dahlmann B,
Messmer BJ, Seghaye MC. Attentional
dysfunction in children after corrective
cardiac surgery in infancy. Ann. Thorac.
Surg. 83(4), 1425–1430 (2007).
Robinson JD, Zimmerman FJ, De Loera O,
Heitschmidt M, Hijazi ZM. Cardiac
conduction disturbances seen after
transcatheter device closure of muscular
ventricular septal defects with the
AMPLATZER occluder. Am. J. Cardiol.
97(4), 558–560 (2006).
Amin Z, Cao QL, Hijazi ZM. Closure of
muscular ventricular septal defects:
transcatheter and hybrid techniques. Catheter.
Cardiovasc. Interv. 72, 102–111 (2008).
•
24
ventricular septal defects. J. Thorac.
Cardiovasc. Surg. 115, 848–856
(1998).
Expert Rev. Cardiovasc. Ther. 8(5), (2010)