Rev Bras Cardiol Invasiva.
2013;21(4):384-9
Original Article
Percutaneous Closure of Ostium Secundum Atrial Septal
Defect Using the Memopart™ Occlusion Device
Jorge Luis Haddad1, Gustavo Caires Novaes2, Rafael Brolio Pavão3, Andre Vannucchi Badran4,
Daniel Conterno Lemos5, Igor Matos Lago6, Moyses de Oliveira Lima-Filho7, Geraldo Luiz de Figueiredo8,
Paulo Henrique Manso9, Walter Villela de Andrade Vicente10, Luis Gustavo Gali11,
Minna Moreira Dias Romano12, J. Antonio Marin-Neto13
ABSTRACT
RESUMO
Background: The authors report their initial experience with
the Memopart™ device (Shanghai Shape Memory Alloy Co Ltd,
Shanghai, China) for the occlusion of secundum atrial septal
defect (ASD). Methods: This was a prospective observational
study of a series of patients undergoing percutaneous occlusion
of ASD with right ventricle volume overload and favorable
anatomic characteristics. The procedure was performed by
percutaneous femoral approach. The mean follow-up was 10.3
± 5 months, with clinical and 24-hour echocardiographic evaluations (or before hospital discharge), 1, 3, 6, and 12 months
after implantation. Results: From February/2012 to April/2013,
21 patients, 16 females, mean age 33.1 ± 18.7 years, were
submitted to percutaneous occlusion of an ASD. The average
diameter of the defect was 19.04 ± 6.25 mm and the device
size was 21.42 ± 6.73 mm (8 to 34 mm). Total occlusion of
the defect was observed in all cases before hospital discharge.
During follow-up, all patients were asymptomatic and without
residual shunt. There was no deaths or any other complications in the series. Conclusions: The percutaneous closure
of ASD using a Memopart™ device is an effective and safe
procedure within the limits of this investigation. The device
Oclusão Percutânea de Comunicação Interatrial Tipo
Ostium Secundum com Prótese Memopart
1
Interventional Cardiologist at Hospital das Clínicas da Faculdade de
Medicina de Ribeirão Preto da Universidade de São Paulo. Ribeirão
Preto, SP, Brazil.
2
Resident in Pediatric Interventional Cardiologist at Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade
de São Paulo. Ribeirão Preto, SP, Brazil.
3
Resident in Interventional Cardiology at Hospital das Clínicas da
Faculdade de Medicina de Ribeirão Preto da Universidade de São
Paulo. Ribeirão Preto, SP, Brazil.
4
Resident in Interventional Cardiology at Hospital das Clínicas da
Faculdade de Medicina de Ribeirão Preto da Universidade de São
Paulo. Ribeirão Preto, SP, Brazil.
5
Interventional Cardiologist at Hospital das Clínicas da Faculdade de
Medicina de Ribeirão Preto da Universidade de São Paulo. Ribeirão
Preto, SP, Brazil.
6
Interventional Cardiologist at Hospital das Clínicas da Faculdade de
Medicina de Ribeirão Preto da Universidade de São Paulo. Ribeirão
Preto, SP, Brazil.
7
Ph.D. Interventional Cardiologist at Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo.
Ribeirão Preto, SP, Brazil.
Introdução: Os autores relatam a experiência inicial da oclusão da comunicação interatrial ostium secundum (CIA) com
a utilização da prótese Memopart (Shanghai Shape Memory
Alloy Co Ltd, Shanghai, China). Métodos: Estudo prospectivo
observacional, no qual uma série de pacientes portadores de
defeitos com signiicativa repercussão hemodinâmica e características anatômicas favoráveis ao implante foi submetida
à oclusão percutânea de CIA. O procedimento foi realizado
por via femoral percutânea, pela técnica habitual. O período
de seguimento foi de 10,3 ± 5 meses, com controles clínicos
e ecocardiográicos 24 horas (ou antes da alta hospitalar), 1,
3, 6 e 12 meses após o implante. Resultados: No período
de fevereiro de 2012 a abril de 2013, foram submetidos à
oclusão percutânea de CIA 21 pacientes, sendo 16 do sexo
feminino, com idade média de 33,1 ± 18,7 anos. O diâmetro
médio do defeito foi de 19,04 ± 6,25 mm e o tamanho da
prótese foi de 21,42 ± 6,73 mm (8 a 34 mm). O implante foi
realizado com êxito em todos os casos, veriicando-se oclusão
total no controle antes da alta hospitalar. No seguimento,
8
Interventional Cardiologist at Hospital das Clínicas da Faculdade de
Medicina de Ribeirão Preto da Universidade de São Paulo. Ribeirão
Preto, SP, Brazil.
9
Ph.D. Pediatric Cardiologist at Faculdade de Medicina de Ribeirão
Preto da Universidade de São Paulo. Ribeirão Preto, SP, Brazil.
10
Associate Professor. Cardiovascular Surgeon at Faculdade de Medicina
de Ribeirão Preto da Universidade de São Paulo. Ribeirão Preto, SP, Brazil.
11
Physician at the Echocardiography Sector of Hospital das Clínicas
da Faculdade de Medicina de Ribeirão Preto da Universidade de São
Paulo. Ribeirão Preto, SP, Brazil.
12
Ph.D. Cardiologist and Professor at Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo. Ribeirão Preto, SP, Brazil.
13
Associate Professor. Director of the Hemodynamics and Interventional
Cardiology Unit of Hospital das Clínicas da Faculdade de Medicina de
Ribeirão Preto da Universidade de São Paulo. Ribeirão Preto, SP, Brazil.
Correspondence to: Jorge Luis Haddad. Campus Universitário Monte
Alegre – Avenida Bandeirantes, 3.900 – Monte Alegre – Ribeirão Preto,
SP, Brazil – CEP 14049-900
E-mail: jl.haddad@yahoo.com.br
Received: 09/04/2013 • Accepted: 11/18/2013
© 2013 Sociedade Brasileira de Hemodinâmica e Cardiologia Intervencionista. Published by Elsevier Editora Ltda. All rights reserved.
Haddad et al.
ASD Occlusion With Prosthesis Memopart®
Rev Bras Cardiol Invasiva.
2013;21(4):384-9
385
is user-friendly and has a high rate of immediate occlusion,
even in large defects.
todos os pacientes estiveram assintomáticos e comprovou-se
a persistência da oclusão total do defeito. Não houve mortalidade e nem outras complicações na série. Conclusões: A
oclusão percutânea da CIA utilizando-se prótese Memopart
é um procedimento eicaz e seguro, dentro dos limites desta
investigação. O implante da prótese é simples e apresenta
alto índice de oclusão imediata, inclusive de defeitos de
grandes dimensões.
DESCRIPTORS: Heart septal defects, atrial. Septal occluder
device. Heart defects, congenital. Cardiac catheterization.
DESCRITORES: Comunicação interatrial. Dispositivo para
oclusão septal. Cardiopatias congênitas. Cateterismo cardíaco.
O
Universidade de São Paulo (HCFMRP-UPS), Brazil and
was approved by the institution’s ethics committee. All
patients or their legal guardians signed an informed
consent after being informed about the purposes of
the study.
stium secundum atrial septal defect (ASD),
located in the oval fossa, constitutes approximately 80% of ASDs.1 Percutaneous occlusion
should be performed in cases in which the anatomy
is favorable, when there are hemodynamic repercussions (class I indication, level of evidence B), in association with orthodeoxia platypnea syndrome (class
IIa indication, level of evidence B), or when there is
a history of paradoxical embolism (class IIa indication, level of evidence C).2 Approximately 85% of the
ASDs have essential structural factors that determine
favorable anatomy for percutaneous occlusion, which
are: stretched defect diameter < 42 mm, which is the
maximum diameter of the available prostheses, and
borders with dimensions ≥ 5 mm, with the exception
of the aortic or anterosuperior border.
The most commonly used devices for percutaneous
closure are double-disc nitinol occlusion devices, which
are self-centering, retrievable, and repositionable; easy
to handle; and have high success rates in ASD occlusion. These prostheses consist of numerous ilaments of
nitinol (a nickel and titanium alloy), welded at their
ends and molded to form a central waist, which acts
as a stent in the communication oriice of two discs,
a larger left disc and a smaller right disc. The different
types of this prosthesis vary slightly in relation to the
nitinol ilament thickness, the laps inserted into the
discs, their dimensions in relation to the central waist,
and the device ixation system to the delivery cable.
This study aimed to report the results of a prospective series of patients undergoing percutaneous closure
of ASD with the Memopart device (Shanghai Shape
Memory Alloy Co. Ltda., Shanghai, China).
METHODS
Study design
This was a prospective, longitudinal, and observational cohort study, performed in a single center, from
February 2012 to April 2013, of patients submitted to
percutaneous ASD occlusion using Memopart device.
The study was performed at the Hemodynamics and
Interventional Cardiology Laboratory of Hospital das
Clínicas, Faculdade de Medicina de Ribeirão Preto,
Inclusion criteria
Patients with ASD that participated in the study
were referred to HCFMRP-USP with the following
clinical, anatomical, and hemodynamic characteristics:
weight > 25 kg; dilation of the right cardiac chambers
visualized during echocardiographic evaluation; QP/
QS ratio > 1.5; pulmonary arterial pressure ≤ 2/3 of
the systemic level; pulmonary vascular resistance < 5
UW; defect diameter < 42 mm; defect borders > 5mm,
except the retroaortic border; signing of the informed
consent approved by the Institutional Ethics Committee.
Exclusion criteria
Patients with other associated congenital or acquired
heart diseases, with indication of surgical correction;
with thin, hypermobile, or deicient ASD borders; those
with active infection of any kind or infectious process
in the previous month; patients with hypercoagulable
syndrome, with contraindication to antiplatelet medication, were excluded from the study.
PROSTHESIS
Memopart (Figure 1) is a prosthetic device manufactured with ilaments of nitinol, a nickel and titanium
metal alloy at a ratio (in relation to atomic weight)
of 55% and 45%, respectively. The set of ilaments is
welded together at the ends, forming a bundle that
has pins at both ends. The bundle is then molded, at
high temperature, as a double disc of different sizes,
with a waist in the middle, which acts as a centering mechanism and positions itself in the defect as a
stent. The pin of the smaller disk, which is the right
one, has a bolt and nut system, which is screwed into
the delivery cable. The prosthesis is ixed in delivery
cable and stretched, to be introduced in the carrier and
transferred to the delivery sheath. Due to the thermal
memory of nitinol, the device, when externalized,
regains its original shape.
386
Haddad et al.
ASD Occlusion With Prosthesis Memopart®
Rev Bras Cardiol Invasiva.
2013;21(4):384-9
The diameter of the central disk determines the
size of the device, which ranges from 6 mm to 42
mm, with 1-mm increments between the sizes from 6
mm to 20 mm and 2-mm increments between sizes
22 mm to 42 mm. The technical characteristics of the
prostheses and releasing sheaths are shown in Table 1.
Procedure
The procedures were performed by femoral approach under general anesthesia, with transesophageal
echocardiography. Unfractionated heparin was administered at a dose of 100 IU/kg, as well as antimicrobial
prophylaxis with irst-generation cephalosporin. The
ASD size was determined by static balloon catheter
technique, and the diameter at which there was low
cessation at color Doppler was measured by luoroscopy and echocardiography. The implantation technique
of the double-disc nitinol prostheses has been often
described by other authors.3,4 Briely, the prosthesis is
soaked in saline solution to remove air from the mesh
and patches; the right disc pin is screwed onto the
delivery cable; the prosthesis is then inserted into the
carrier and transferred to the delivery sheath, previously
positioned in the left superior pulmonary vein. The left
disk is externalized in the left atrium, near the mouth
of the pulmonary vein, the delivery sheath is removed
from the pulmonary vein and the set is subsequently
retracted, until the disc is anchored in the interatrial
septum. Keeping the release cable ixed, the sheath is
withdrawn until the externalization of the right disk.
After conirming the appropriate position of the device
A
D
B
Dilator
92 cm - PTFE
Delivery sheath
80 cm - PTFE
in three basic echocardiographic views (short axis, bicaval, and four-chamber) and the absence of signiicant
residual low, the prosthesis is released, unscrewing the
delivery cable by clockwise rotation (Figures 2 and 3).
Several variations of this basic technique are
sometimes implemented for proper positioning of the
prosthesis according to the different anatomical ASD
characteristics. These include the partial opening of
the waist, before anchoring the left disk; the initial
approach from the right or left superior pulmonary
vein; and the partial externalization of the left disk in
the pulmonary vein, followed by sheath withdrawal to
the right atrium, in order to impact the right disk irst
in the interatrial septum.5,6
Procedural success was deined when the prosthesis
was implanted with proper placement and no residual
shunt or < 2 mm on transesophageal echocardiogram
performed during the procedure.
Follow-up
Patients were evaluated clinically and with transthoracic echocardiography before hospital discharge
and after one, three, six, and 12 months. They were
treated during this period with acetylsalicylic acid in
a single daily dose of 5 mg/kg (maximum dose of 100
mg/day) for six months. In adult patients, clopidogrel
was associated, at a dose of 75 mg/day for six months.
Antibacterial prophylaxis was prescribed, in the event
of surgical or interventional procedures during the irst
six months of evolution.
C
Hemostatic
valve
Release cable
120 cm - Stainless steel
Carrier
11/14 cm - PTFE
Figure 1 – Prosthesis, and set of delivery and release. (A) Schematic representation of the prosthesis: (1) Left disc diameter, (2) Right disc diameter,
(3) Central disc diameter, (4) Total thickness of the device. (B) Prosthesis discreetly stretched at the proximal and distal ends, showing both the upper
left and lower right discs, in addition to the central disc. (C) Prosthesis mounted on the delivery system, partially externalized, with the right disk
still not fully exposed. (D) The different components of the delivery and release system.
Haddad et al.
ASD Occlusion With Prosthesis Memopart®
Rev Bras Cardiol Invasiva.
2013;21(4):384-9
387
Table 1
Clinical, echocardiographic, and hemodynamic parameters of patients
Atrial septal defect diameter
Patient
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
Age
(years)
Weight
(Kg)
Gender
Transesophageal
echocardiogram
8
45
35
3
15
20
75
37
47
9
54
41
57
9
27
29
39
44
51
12
38
35
67
55
16
83
87
52
94
66
29
54
69
79
25
55
78
105
84
60
31
99
F
F
F
F
F
M
F
F
F
M
M
F
F
F
F
F
F
F
F
M
M
7
8
18
14
13
12
6
24
15
10
20
15
17
16
15
20
10
21
10
13
24
Residual flow
Cardiac
Prosthesis
catheterization QP-QS
(mm)
7
14
23
18
16
11
14
32
17
17
26
18
21
18
24
24
18
27
10
16
29
1.5
1.9
3.3
4.8
2.6
1.7
1.9
1.9
3.0
2.9
4.6
2.7
1.9
1.8
3.0
2.6
2.0
2.5
1.6
1.7
2.7
8
16
24
20
18
12
16
34
20
18
30
22
22
24
26
28
20
30
12
18
32
Immediate
24
hours
No
No
Minimum
No
No
No
No
No
No
No
No
No
No
No
No
Minimum
No
Minimum
No
Minimum
Minimum
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
No
QP/QS = pulmonary low/systemic low; F = female; M = male.
Statistical analysis
The continuous variables were described as maximum
and minimum values, as well as means and standard
deviations. Categorical variables were described as
frequencies or percentages.
RESULTS
A total of 21 patients underwent the procedure,
of whom 16 were females, with mean age of 33.1 ±
18.7 years and mean weight of 63.0 ± 24.81 kg. Transesophageal echocardiography disclosed the presence
of single septal defect in all patients, with maximum
diameter between 7 and 24 mm (14.66 ± 5.1 mm).
All treated patients had borders > 5 mm, but eight
patients had deicient or absent aortic border. Clinical,
echocardiographic and hemodynamic parameters are
shown in Table 1.
Cardiac showed revealed a mean pulmonary-tosystemic low ratio (QP/QS) of 2.47 ± 1.14, systolic
pulmonary artery pressure (SPAP) of 35.2 ± 9.5 mmHg,
and pulmonary arteriolar resistance of 0.9 ± 0.5 UW.
The ASD diameter measured by balloon-catheter ranged between 7 and 32 mm (19.04 ± 6.25 mm) and
determined the selection of the prosthesis; a total of
21 devices were used, varying in size between 8 and
34 mm (21.42 ± 6.73 mm).
Implantation was possible in all patients. In two
patients, it was necessary to position the sheath in the
right superior pulmonary vein; in one patient, the distal
portion of the left disc was released inside the pulmonary
vein and the sheath was withdrawn up to the right disk
opening, in the right atrium; the set was then pushed and
anchored in the interatrial septum, and the left disc was
released from the pulmonary vein, impacting on the left
side of the septum (30-mm prosthesis).
In all cases, the prosthesis was implanted without
technical dificulties. In ive patients (24%), there was
minimum residual low immediately after implantation,
through the central portion of the prosthesis, which
disappeared at the control Doppler echocardiography
prior to discharge. None of the patients needed intensive care and all were discharged on the day after the
implant. There were no deaths or other periprocedural
complications in this series.
During the mean follow-up period, which was
10.3 ± 5 months, all patients were free of cardiovascular symptoms and the echocardiographic assessment
showed absence of residual low. In 18 cases (86%),
388
Haddad et al.
ASD Occlusion With Prosthesis Memopart®
Rev Bras Cardiol Invasiva.
2013;21(4):384-9
A
E
B
F
A
D
C
C
G
E
D
B
H
Figure 2. Atrial septal defect of 16 mm without aortic border: short
axis (A, B, C and D) and Bicaval or long axis (E, F, G and H). (A and
E) Diameter of the defect. (B and F) Left-right low in color Doppler.
(C and G) Adequate positioning of the prosthesis, embracing the aorta
in the short axis and the borders of both cavas in the long axis. (D
and H) No residual low.
there was normalization of the right ventricle size; in
three patients, aged > 50 years, there was persistent right
ventricular dilation; however, with a signiicant reduction in its size. There were no late complications such
as erosion, pericardial effusion, arrhythmias, thrombus
formation, or infective endocarditis.
DISCUSSION
The literature review disclosed a single series
published with 73 patients undergoing percutaneous
closure of ASD using this prosthesis, performed at the
First People’s Hospital of Yanzhou (China).7
In this series, the rate of complete occlusion within
the irst 24 hours was 100%. In ive patients, minimal
central residual low was observed through the implant
immediately after implantation, which may be explained
by one of the occlusion mechanisms: the thrombogenicity of polyester laps and the fact that clotting time of
patients is variable. This adds to the fact that, during
the procedure, complete anticoagulation is achieved.
Complete occlusion was veriied in small, moderate,
and large defects, similarly to cases from published
studies using nitinol double-disc prostheses.8-13
F
Figure 3. Atrial septal defect (ASD) with no aortic border. (A) Echocardiogram in the short axis. (B) Color Doppler showing left-right low. (C)
Measuring balloon with discreet waist, determining an ASD diameter
of 19.5 mm. (D) Color Doppler with the implanted device and the
absence of residual low. (E and F) Fluoroscopy in the left anterior
oblique view of the implanted prosthesis, still attached to the delivery
cable and under mild tension (C), and released prosthesis showing a
more vertical position (D). The arrows show the greater separation of
the disks at the top, where the prosthesis embraces the aorta.
It is believed that the absence of complications
was due to the following factors: the prosthesis lexibility, ease of implantation, and accurate selection of
patients. All patients had optimal anatomic characteristics
for implant, and borders of appropriate thickness and
size > 5 mm, with the exception of the anterosuperior
border, where the graft can be anchored, embracing
the posterior aspect of the aorta.
The follow-up period of this study is considered
too short to exclude more severe and at times lateonset complications, i.e., the erosion of the atrial
walls with cardiac tamponade or of aortic wall with
formation of fistula at the left atrium. 14-16 However, the
following precautions were taken when selecting the
device to reduce the likelihood of this complication:
prevent prosthesis oversizing, do not implant a device
with left disk size greater than the maximum length
of the atrial septum, and even in cases with deficient
anterosuperior border, anchor the device embracing
the posterior portion of the aorta, so that the borders
of the discs, which have a higher erosion potential,
do not come into contact with the juxtaposition of
the atrial and aortic walls.
Rev Bras Cardiol Invasiva.
2013;21(4):384-9
CONCLUSIONS
The Memopart prosthesis has adequate lexibility
and low proile, and was easy to handle and implant.
Its use in percutaneous closure of ostium secundum
ASDs with favorable anatomy was shown to be a safe
and effective procedure, even in large-size defects
within the limits of this investigation. A larger series
with longer follow-up is needed to assess the possible
occurrence of late-onset complications.
CONFLICTS OF INTEREST
The authors declare no conlicts of interest.
ACKNOWLEDGEMENTS
The Lepu Medical Systems material used in the
procedures was donated to the USP-HCFMRP by Vallux Comércio de Materiais Hospitalares (Goiânia, GO,
Brazil), the representative in Brazil of Lepu (Shanghai
Shape Memory Alloy Co. Ltda., Shanghai, China).
REFERENCES
1. European Society of Cardiology. ESC Guidelines for the
management of grown-up congenital heart disease (new
version 2010). Eur Heart J [Internet]. 2010 [cited 2013 Oct
21];31:2925-57. Available from: http://eurheartj.oxfordjournals.
org/content/31/23/2915.full.pdf
2. Warnes CA, Williams RG, Bashore TM, Child JS, Connolly
HM, Dearani JA, et al. ACC/AHA 2008 guidelines for the
management of adults with congenital heart disease: a report
of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writting Committee to Develop Guidelines on the Management of Adults
With Congenital Heart Disease). Developed in Collaboration
With the American Society of Echocardiography, Heart
Rhythm Society, International Society for Adult Congenital
Heart Disease, Society for Cardiovascular Angiography and
Interventions, and Society of Thoracic Surgeons. J Am Coll
Cardiol.2008;52(23):e143-263.
3. Masura J, Gavora P, Formanek A, Hijazi ZM. Transcatheter
closure of secundum atrial septal defects using the new selfcentering amplatzer septal occluder: initial human experience.
Cathet Cardiovasc Diagn. 1997;42(4):388-93.
View publication stats
Haddad et al.
ASD Occlusion With Prosthesis Memopart®
389
4. Omeish A, Hijazi ZM. Transcatheter closure of atrial septal
defects in children & adults using the Amplatzer Septal Occluder. J Interven Cardiol. 2001;14(1):37-44.
5. Harper RW, Mottram PM, McGaw DJ. Closure of secundum
atrial septal defects with the Amplatzer septal occluder device: techniques and problems. Catheter Cardiovasc Interv.
2002;57(4):508-24.
6. Pinto R, Jain S, Dalvi B. Transcatheter closure of large atrial
septal defect in children using the left atrial disc engagementdisengagement technique (LADEDT) – technical considerations
and short term results. Catheter Cardiovasc Interv. 2013 Feb14.
[Epub ahead of print]
7. Sun WF, Dong ZF, Gong K, Zhang GP, Cui T, Xia YD, et al.
Transcatheter closure with use of the SHSMA occluder in 180
patients with congenital heart defects: preliminary results. Tex
Heart Inst J. 2010;37(5):531-7.
8. Du ZD, Hijazi ZM, Kleinman CS, Silverman NH, Larntz K;
Amplatzer Investigators. Comparison between transcatheter and
surgical closure of secundum atrial septal defect in children
and adults: results of a multicenter nonrandomized trial. J Am
Coll Cardiol. 2002;39(11):1836-44.
9. Kannan BRJ, Francis E, Sivakumar K, Anil SR, Kumar RK.
Transcatheter closure of very large (> or = 25 mm) atrial
septal defects using the Amplatzer septal occluder. Catheter
Cardiovasc Interv. 2003;59(4):522-7.
10. Pedra CAC, Pedra SRF, Costa RN, Braga SLN, Esteves CA,
Fontes VF. Experiência inicial no fechamento percutâneo da
comunicação interatrial tipo Óstio Secundum com a prótese
Figulla. Rev Bras Cardiol Invasiva. 2010;18(1):81-8.
11. Chamié F, Chamié D, Ramos S, Simões LC, Rossi Filho RI,
Tress JC, et al. Oclusão da comunicação interatrial com a
nova prótese atriasept-CARDIA: experiência inicial. Rev Bras
Cardiol Invasiva. 2009;17(1):91-101.
12. Costa RN, Ribeiro MS, Pereira FL, Pedra SR, Jatene MB, Jatene IB, et al. Percutaneous versus surgical closure of atrial
septal defects in children and adolescents. Arq Bras Cardiol.
2013;100(4):347-54.
13. Masura J, Gavora P, Podnar T. Long-term outcome of transcatheter secundum-type atrial septal defect closure using amplatzer
septal occluders. J Am Coll Cardiol. 2005; 45(4):505-7.
14. Chessa M, Carminati M, Butera G, Bini RM, Drago M, Rosti L,
et al. Early and late complications associated with transcatheter
occlusion of secundum atrial septal defect. J Am Coll Cardiol.
2002;39(6):1061-5.
15. Preventza O, Sampath-Kumar S, Wasnick J, Gold JP. Late
cardiac perforation following transcatheter atrial septal defect
closure. Ann Thorac Surg. 2004;77(4):1435-7.
16. Taggart NW, Dearani JA, Hagler DJ. Late erosion of na
amplatzer septal occluder device 6 years after placement. J
Thorac Cardiovasc Surg. 2011;142(1):221-2.