2. • Atrial septal defect (ASD) is the most common congenital lesion in adults
after bicuspid aortic valve.
• Although patients with this defect are often asymptomatic until adulthood,
potential complications of an untreated ASD include atrial arrhythmias,
paradoxical embolization, cerebral abscess, right ventricular failure, and
pulmonary hypertension that can become irreversible and lead to right-to-left
shunting (Eisenmenger syndrome).
3. PREPROCEDURAL ASSESSMENT
• Preprocedural assessment in patients with indications for ASD closure includes
review of the transthoracic echocardiogram (TTE).
• Some patients require additional testing such as transesophageal echocardiogram
(TEE), cardiovascular computerized tomography (CT), or cardiac magnetic
resonance (CMR) imaging to confirm the diagnosis and identify or exclude
associated defects prior to surgical or percutaneous closure.
• In patients with pulmonary hypertension, cardiac catheterization is usually
recommended to determine the best management strategy.
4. • Conditions that are likely to require surgical correction should be identified prior to
intervention:
• Primum ASD, sinus venosus ASDs, and coronary sinus defects require surgical closure.
• Primum ASD is usually accompanied by a cleft mitral valve.
• A cleft mitral leaflet should be repaired at the time of ASD closure, even if associated mitral
regurgitation is not severe, to avoid the need for another operation since mitral regurgitation
usually progresses.
• Primum ASDs may also be associated with tricuspid valve abnormalities, left ventricular
outflow tract obstruction, ventricular septal defects, and a more extensive defect involving
the atrioventricular septum (atrioventricular septal defect).
5. • Sinus venosus ASDs are usually associated with one or more anomalous right-sided
pulmonary veins.
• Sinus venous ASDs and the associated anomalous veins are often missed on standard TTE.
• Agitated saline contrast administered during a TTE should demonstrate prompt filling of
the left heart chambers with bubbles in the presence of a sinus venosus atrial septal defect.
• Additional imaging options include TEE, CT, or CMR. However, these types of ASDs and
anomalous pulmonary veins can be missed even with advanced imaging techniques.
• These defects should be sought in patients with right heart enlargement.
• Our practice is to delineate the anatomy, including all of the anomalous pulmonary veins,
before the patient goes to the operating room for surgical intervention.
6. • Coronary sinus defects (also known as "unroofed coronary sinus") are often
missed despite echocardiography.
• They are often associated with left-sided superior vena cava and may
accompany other congenital anomalies including ostium primum or
secundum ASDs.
• Observation of agitated saline in the left atrium initially, rather than the right
atrium, after injection into a left-sided arm vein suggests the presence of a
coronary sinus defect and left-sided superior vena cava.
7. • Multiple ASDs may be present (eg, concurrent secundum and primum
ASDs).
• Some patients with multiple small secundum ASDs are amenable to
percutaneous closure; others require surgical closure.
8. • Some patients with ASDs have concomitant valve disease (in addition to cleft mitral
valve with primum ASD as discussed above).
• Moderate or more tricuspid regurgitation may persist after ASD closure in the adult.
• We favor surgical ASD closure when there is moderate or more tricuspid
regurgitation to facilitate both ASD closure and tricuspid repair at the time of
operation
9. CHOICE OF CLOSURE PROCEDURE
• Percutaneous transcatheter device closure is an alternative to surgical repair
for the majority of patients with secundum ASDs. Surgical closure is
recommended for patients with secundum ASD requiring closure when
percutaneous repair is not feasible or appropriate .
• Anatomic requirements for percutaneous closure are discussed below.
• A secundum ASD with a large atrial septal aneurysm or a multifenestrated
atrial septum requires careful evaluation to determine whether percutaneous
device closure is appropriate
10. • Sinus venosus, coronary sinus, and ostium primum defects are preferably
closed surgically, as they are not generally amenable to percutaneous device
closure (although there are case reports of percutaneous closure of these
defects).
11. • Percutaneous versus surgical closure for secundum ASD —
• Observational studies comparing surgical and percutaneous transcatheter closure of
secundum ASD suggest that mortality rates are similar, the rate of procedural success is
comparable or slightly better with surgery, and the rate of early complications and length of
hospital stay are reduced with the percutaneous approach.
• Differing types of complications occur following the two procedures as illustrated by the
following studies.
12. • An atrial septal aneurysm (ASA) is defined as redundant and mobile
interatrial septal tissue in the region of the fossa ovalis with phasic excursion
of at least 10 to 15 mm during the cardiorespiratory cycle.
• ASA is commonly associated with patent foramen ovale or one or more
ASDs
13. • A perforated aneurysm may be associated with a significant left-to-right shunt and
present with clinical and hemodynamic features of an ASD.
• Perforated aneurysms can be closed surgically or percutaneously, depending upon
their morphology.
• In a retrospective review of 50 patients, perforated aneurysms were classified as
follows
14.
15. Atrial Septal Aneurysm
• Type A - aneurysm with persistent foramen ovale
• Type B - aneurysm with single ASD
• Type C - aneurysm with two perforations
• Type D - aneurysm with multiple perforations
16. PERCUTANEOUS CLOSURE OF
SECUNDUM ASD
• Percutaneous device closure is an alternative to surgical closure in patients
with secundum ASDs who have appropriate anatomic characteristics.
• Two devices have both US Food and Drug Administration approval and
CE-mark and are commercially available in the United States and Europe for
percutaneous ASD closure the Amplatzer Septal Occluder and the Gore
CARDIOFORM Septal Occluder.
• The Occlutech ASD Occluder, the Ceraflex ASD Occluder, and the Nit-
Occlud ASD-R have received CE-mark and are in clinical use in Europe
17.
18.
19.
20.
21. • Of note, the Gore CARDIOFORM Septal Occluder does not have self-
centering properties, which limits its use for larger defects and it is used
mostly for patent foramen ovale closure.
• However, in selected patients with centrally located ASDs or multiperforated
atrial septum, the CARDIOFORM Septal Occluder is a valid alternative
device with less foreign material and excellent occlusion properties.
22. • The Amplatzer septal occluder and the CARDIOFORM device are characterized by
relatively stiff delivery mechanisms, so the angulation of the device changes after device
release.
• In contrast to these occluders, the Occlutech and Ceraflex occluders have more flexible
delivery mechanisms, which enable optimal septal alignment prior to device release.
• The device remains in its final configuration and does not change its angulation at release.
• An additional advantage of the flexible properties of the Occlutech and Ceraflex occluders
is that the left atrial disc has less of a tendency to slip along the aortic root into the right
atrium during device placement, and hence, fewer adjunctive procedures (eg, device
deployment with an additional balloon) are needed.
23. • A few other devices that had been approved and were previously used for
ASD closure are no longer available, including the CardioSEAL Septal
Occlusion System, the STARFlex device (a next-generation version of the
CardioSEAL device), and the Gore HELEX (a predecessor of the
CARDIOFORM device).
• The following discussion will review the efficacy and complications
associated with percutaneous device closure of secundum ASD.
24. Contraindications and cautions
• Pulmonary hypertension — Severe fixed pulmonary hypertension is considered a
contraindication to ASD closure.
• However, advances in the medical management of patients with pulmonary vascular
disease together with the development of novel percutaneous closure techniques
may make ASD closure feasible in this setting.
• It has been suggested that patients with a net left-to-right shunt, a pulmonary
vascular resistance less than 800 to 960 dyne sec cm (-5) m2 (10 to 12 Wood units),
and a resting systemic arterial oxygen saturation ≥90 percent might benefit from
ASD closure
25. • The potential efficacy of percutaneous closure was demonstrated in a report of 29
patients with a secundum ASD and a baseline peak pulmonary artery pressure >40
mmHg (mean 65 mmHg) in whom an Amplatzer device was implanted .
• Complete ASD occlusion was achieved in 28 patients (97 percent). Immediately
after the procedure, the mean peak pulmonary artery pressure decreased to 54
mmHg; at a mean of 21 months, it decreased further to 31 mmHg.
• There were no procedural complications. Functional status was improved after the
procedure and was maintained at a mean of 21 months.
• Six of 12 patients who had AF at baseline recovered sinus rhythm by discharge.
26. Diastolic dysfunction
• Unrecognized left ventricular diastolic dysfunction may be present in older patients with ASDs.
• The presence of the left-to-right shunt at the atrial level may function to "offload" the stiff left
ventricle in these patients.
• One series demonstrated that temporary test occlusion of the ASD with a soft balloon catheter
in adult patients may help identify individuals whose left heart filling pressures will worsen if
device closure is performed .
• Our practice is to generally perform ASD test occlusion in patients 40 years old or older.
• If the mean left atrial or pulmonary capillary wedge pressure or left ventricular end-diastolic
pressure increases significantly with test occlusion, then we forego device closure in most cases.
• Further research needs to be conducted to identify a threshold increase in filling pressures, above
which ASD closure may be detrimental.
32. • Anatomic requirements — Percutaneous device closure is generally
applicable only to secundum ASDs .
• Sinus venosus, primum, and coronary sinus defects are not often amenable
to percutaneous repair, although cases of percutaneous repair of these
defects have been reported
33. • The ideal lesion for percutaneous closure is a secundum defect ≤38 mm in diameter
with a rim of tissue around the defect of at least 5 mm to prevent obstruction of
the coronary sinus, right pulmonary veins, venae cavae, or atrioventricular valves.
• The presence of a "retroaortic" superior-anterior atrial septal rim is favorable for
device closure, but septal deficiency in this region is common and not necessarily a
contraindication to percutaneous closure.
• Retroaortic rim deficiency has been associated with risk of erosion, as discussed
below.
34. • Approximately one-half to two-thirds of secundum ASDs in adults meet these
criteria .
• While smaller defects are often more amenable to device closure, larger defects can
also be closed percutaneously.
• The Amplatzer device is available in sizes ranging from 4 to 38 mm, reflecting the
diameter of the central device of the waist and generally correlating with the size of
the ASD to be closed.
• By comparison, the CARDIOFORM device comes in only three sizes (20, 25, and
30 mm), reflecting the diameter of the device disk at full deployment.
• The CARDIOFORM device can be used to close defects up to approximately 18
mm in diameter.
• Closure of multiple ASDs has been performed using one or more closure devices,
including use of an Amplatzer multifenestrated "cribriform" septal occluder device
or one or more CARDIOFORM device .
35. • Rarely, secundum ASD is associated with a partial anomalous pulmonary
venous connection that should generally be managed with surgical ASD
closure and concomitant baffling of the anomalous pulmonary venous
return.
• Thus, prior to percutaneous closure, a search for anomalous pulmonary veins
or other concurrent lesions that might require surgery should be undertaken,
particularly if right heart chamber enlargement is out of proportion to the
size of the ASD.
36. Echocardiographic monitoring
• The use of transesophageal echocardiography (TEE) or intracardiac echocardiography (ICE) can facilitate the deployment
of percutaneous ASD closure devices.
• Measurement of the size and location of the ASD by TEE can help select the appropriate device.
• In addition, TEE and ICE can be used to guide the procedure in real time, an approach that may eliminate the need for
fluoroscopy.
• Two- and three-dimensional (3D) TEE is particularly helpful when multiple devices are inserted to close multiple ASDs .
• TEE during the procedure can also determine whether disruption of systemic or pulmonary venous inflow or valve
function occurs with device placement.
37. • In one series, 94 patients underwent ICE during percutaneous closure of an ASD or patent foramen ovale (PFO) .
• All devices were deployed successfully. During the procedure, ICE identified a previously unrecognized anatomical
diagnosis in 32 patients (an additional ASD or PFO, a redundant atrial septum, or an atrial septal aneurysm).
• Procedural complications occurred in four patients: atrial fibrillation (AF) in three and supraventricular tachycardia in one.
Two of the arrhythmias resolved spontaneously and two required cardioversion with no recurrence.
• 3D echocardiography enables direct and complete visualization of the ASD, so that the area of the defect can be estimated
and the anatomy of the entire interatrial septum can be defined.
• This 3D information facilitates optimal deployment and positioning of all types of interatrial closure devices.
• Clinical series suggest that percutaneous ASD closure can be safely and effectively be performed using only
echocardiographic guidance without fluoroscopy
38. Outcomes of percutaneous closure
Observational studies of percutaneous closure have generally reported efficacy
rates similar to surgical closure with shorter hospital stays and lower rates of
complications .
Defect closure is associated with a reduction in left atrial volume and
improvements in right and left ventricular function and functional capacity
even in adults who were asymptomatic at baseline.
39. Complications
• Complications associated with transcatheter closure of a secundum ASD
include device embolization or malposition, access site complications, atrial
arrhythmias, atrioventricular conduction block (often transient),
erosion/perforation, and sudden death (in at least some cases related to
erosion)
40. • Early — The type and frequency of early complications were evaluated in a report of 417
patients (mean age 27 years) who underwent secundum ASD closure with the
AMPLATZER or CardioSEAL/STARFlex device .
• Thirty-four patients (8.6 percent) experienced a complication during hospitalization:
●Device embolization or malposition requiring surgery in 2.4 percent and managed
percutaneously in 1 percent.
●AF or supraventricular tachycardia in 2.4 percent.
●Other complications (heart block, pericardial effusion, thrombus formation on the left
atrial portion of the device, iliac vein dissection, groin hematoma) in 2.2 percent.
41. • A similar rate of early complications (11.5 percent) and no mortality were reported in a multi-center study of 688 patients
undergoing ASD closure with the Amplatzer, CardioSEAL/STARflex, or HELEX septal occluder .
• Device embolization occurred in 1.4 percent of patients with 0.4 percent of cases requiring surgical device removal.
• In contrast, in another series of 124 patients, 6.5 percent required surgery for device malposition or embolization .
• Embolized Amplatzer ASD occluders may be removed relatively safely by snaring the detachment hub and withdrawing
through an adequately sized sheath.
• The Occlutech and Ceraflex occluders, especially the larger sizes, are more difficult to be removed since a snare may slip
off the detachment hub. The additional use of a dedicated biotome can be very helpful in these rare cases .
• Transient atrioventricular block has been described with a frequency ranging from 1 to 6 percent .
• Atrioventricular block may be more common with larger devices and smaller patients. This problem appears to resolve or
improve spontaneously in most cases.
42. • Thrombus formation — Antiplatelet therapy (aspirin and clopidogrel) is given for at least six months to all
patients receiving a percutaneous closure device to protect against thrombus formation .
• Thrombus formation can occur in the left and/or right atrium .
• Anticoagulation is used in patients with ASD closure devices who have another indication for anticoagulation
therapy, such as AF.
• The frequency with which thrombus formation occurs was evaluated in a review of 407 consecutive patients
with an ASD and 593 consecutive patients with a PFO who were treated with a variety of devices . The
following findings were noted:
●Thrombus on the device was detected by TEE at four weeks in 14 patients (1.4 percent) and at six months in
six patients (0.6 percent).
The overall rate of thrombus formation was 1.2 percent in patients with an ASD and 2.5 percent in patients
with a PFO.
43. • After the investigators discontinued use of heparin therapy after implantation, thrombus
occurred in only 1 of 183 patients (0.5 percent) treated with aspirin and clopidogrel.
●Thrombus formation was significantly more common with the CardioSEAL and STARFlex
devices than with the Amplatzer device (5.9 versus 0 percent).
An intermediate rate of 3.6 percent was noted with the Atrial-Septal-Defect-Occlusion-System
(ASDOS) device.
●The thrombus resolved in 17 of 20 patients after anticoagulation with heparin and/or warfarin; in
the remaining three patients, the thrombus was removed surgically. Four of the 20 patients suffered
embolic events (strokes in three and a transient ischemic attack in one).
• Left atrial thrombus formation with transient ischemic attacks has been described as late as three
years after implantation
44. EFFECT OF DEFECT CLOSURE ON
RISK OF ATRIAL ARRHYTHMIAS
• Atrial arrhythmias, primarily atrial fibrillation and atrial flutter, occur in approximately 20 percent of adult patients with an ASD and are often
the presenting symptom.
• The risk of these arrhythmias increases with patient age (especially over age 40) and with higher pulmonary artery pressures .
• In a report of 211 adults, for example, the incidence of AF or atrial flutter prior to surgery was 1 percent for those aged 18 to 40, 30 percent
for those aged 40 to 60, and 80 percent in those over the age of 60.
• Observational data suggest that ASD closure may reduce but does not eliminate the risk of atrial tachyarrhythmias.
• The effect of surgical or percutaneous defect closure on the prevalence of atrial arrhythmias was evaluated by a systematic review, including
26 studies in which a total of 1841 patients (with median or mean age at least 18 years prior to intervention) underwent surgical closure and
945 patients underwent percutaneous closure .
• Meta-analysis demonstrated a reduction in the prevalence of atrial tachyarrhythmias after ASD closure (odds ratio [OR] = 0.66, 95% CI 0.57-
0.77).
• This effect was found after both surgical closure (OR = 0.72, 95% CI 0.60-0.87) and percutaneous closure (OR = 0.49, 95% CI 0.32-0.76). A
significant decline in atrial tachyarrhythmias was seen both at <30 days and midterm (30 days to five years) follow-up.
• Limitations of the analysis include differences in methods for monitoring arrhythmias before and after closure in most of the studies.
45. • The risk of AF after ASD closure is presumably primarily related to irreversible
factors, such as incomplete atrial remodeling, that predispose to the arrhythmia.
• Surgical techniques, such the Maze procedure performed at the time of surgical
ASD closure, decrease the long-term incidence of AF in selected patients.
• This procedure involves the placement of incisions or cryolesions in the atria to
interrupt the macroreentrant circuits that sustain atrial flutter and AF .
• The use of radiofrequency ablation to create endocardial lesions is also effective in
preventing recurrences of AF, although data are limited in the patients with ASD
