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ORIGINAL ARTICLE

Acta Medica Indonesiana - The Indonesian Journal of Internal Medicine

Transcatheter Closure of Atrial Septal Defects in Adolescents and Adults: Technique and Difficulties

Mulyadi M. Djer1, Nuvi N. Ramadhina1, Nikmah S. Idris1, Dedi Wilson1, Idrus Alwi2, Muhammad Yamin2, Ika P. Wijaya2

1 Department of Child Health, Faculty of Medicine Universitas Indonesia - Cipto Mangunkusumo Hospital, Jakarta Indonesia. 2 Department of Internal Medicine, Faculty of Medicine Universitas Indonesia - Cipto Mangunkusumo Hospital, Jakarta, Indonesia.

Correspondence mail:Department of Child Health, Faculty of Medicine Universitas Indonesia - Cipto Mangunkusumo Hospital. Jl. Diponegoro no. 71, Jakarta 10430, Indonesia. email: muldjer@yahoo.com.

ABSTRAKTujuan: mengevaluasi tindakan penutupan atrial septal defect (ASD) transkateter pada remaja dan dewasa.

Metode: studi seri kasus terhadap pasien yang menjalani tindakan penutupan ASD transkateter di RS Cipto Mangunkusumo Jakarta tahun 2002 sampai 2013. Sebelum penutupan, dilakukan ekokardiografi transesofagus, pengukuran hemodinamik, dan angiografi. Tes oksigen dilakukan jika tekanan arteri pulmonal lebih dari 2/3 tekanan aorta. Jika respons tes oksigen negatif, uji oklusi dengan alat penutup dilakukan. Jika tidak didapatkan kenaikan tekanan arteri pulmonal dan atrium kanan, alat penutup di-release. Hasil: subjek berjumlah 54 orang, 7 (13%) di antaranya lelaki, dan 14 (26%) adalah remaja. Median berat badan 49 (26-75) kg dan ukuran ASD 21 (9.4-39.6) mm. Tindakan dilakukan dalam anestesi umum pada 26% pasien. Tes oksigen dilakukan pada 6/54 (11%) dan tes oklusi pada 1 (2%) pasien. Penutupan ASD berhasil dilakukan pada semua pasien dengan teknik biasa (31%), right pulmonary vein assisted (65%), left pulmonary assisted (2%), atau cutting long sheath (2%). Tidak ditemukan residual ASD atau komplikasi serius. Median waktu floroskopi adalah 29 (SB 18) menit, waktu prosedur 109 (SB 36) menit, dan lama rawat 1 (1-3) hari. Kesimpulan: penutupan ASD pada remaja dan dewasa memiliki angka keberhasilan tinggi.

Kata kunci: penutupan transkateter, atrial septal defect, hipertensi pulmonalis, tes oksigen, tes oklusi.

ABSTRACTAim: to evaluate the results of transcatheter closure of atrial septal defect (ASD) in adolescents and adult.

Methods: a case series of patients undergoing transcatheter closure of ASD in RS Cipto Mangunkusumo, Jakarta during 2002 -2013. Transesophageal echocardiography, hemodynamic study, and angiography were performed before the procedure. Oxygen test was done if PA pressure was more than 2/3 of aortic pressure, followed by an occlusion test if no response observed to determine whether the device could be released. Results: we enrolled 54 patients, of whom 26% were adolescents and 3% were males. Median body weight was 49 (26-75) kg and ASD size was 21 (9.4-39.6) mm. The procedure was done under general anesthesia in 26% of patients. Oxygen test was applied in 11% patients and occlusion test in 2% of patient. Transcatheter closure of ASD was successful in all patients using common technique (31%), right pulmonary vein-assisted (65%), left pulmonary assisted (2%), and cutting long sheath (2%). There was neither residual ASD nor complications observed. Mean fluoroscopy and procedure time were 29 (SD 18) and 109 (SD 36) minutes, respectively. Median hospital stay was 1 (1-3) day. Conclusion: transcatheter closure of ASD in adolescents and adults is safe and effective.

Key words: transcatheter closure, atrial septal defect, device, oxygen test, occlusion test, pulmonary hypertension.

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INTRODUCTIONAtrial septal defect (ASD) is the second most

common acyanotic congenital heart disease that presents at any age.1,2 It may be undetected until adolescence or adulthood. Patients with isolated atrial septal defects will have good outcomes if the diagnosis and management are suitable for the conditions. The size of the defect and relative diastolic filling properties of the right ventricle should be considered in every case. Surgical repair for adult cases of ASD and its results appear less favorable than intervention closure using device.3-6

Transcatheter ASD closure has been shown to be feasible and safe in children, but data in adults are less established.7-11 Amplatzer septal occluder (ASO) is one of the devices that was already recommended by US Food and Drugs Administration (FDA) for ASD closure.12-16 The benefits of using transcatheter closure compared to surgical closure are short hospital stay, no need for cardiopulmonary bypass (CPB), and no scar at the chest wall.3-6

Interartrial communication between the left atrium and right atrium brings the blood from the left atrium to the right atrium, resulting in lung overflow. The body respons to this condition by increasing the pulmonary pressure which could lead to pulmonary hypertension. The ideal age for ASD closure is preschool age between 4 and 5 years old,1,2 and delay in ASD closure until adolescense or adult age is a challenge. The aim of this study was to evaluate the result of transcatheter closure of atrial septal defect (ASD) in adolescents and adults in Cipto Mangunkusumo Hospital Jakarta, Indonesia.

METHODSThis study was a case series non-

comparative from a group of adolescents and adults who underwent transcatheter ASD closure with the Amplatzer® septal occluder at the Integrated Cardiovascular Services, RS Dr. Cipto Mangunkusumo since 2002 until 2013. The diagnosis of ASD was established by the history, physical examination, chest radiography, electrocardiography and confirmed by transthoracic echocardiography. All patients

underwent 2D transthoracic echocardiography to assess defect location, size with respect to anterior and posterior rim length. Colour Doppler echocardiography was performed to examine the shunts, left-to-right shunt, bidirectional shunt or right-to-left shunt.

Continuous-wave echocardiography was done to measure the pressure gradient from tricuspid valve in order to predict pulmonary arterial pressure. Once the diagnosis of ASD was established, all patients underwent the trans-esophageal echocardiography (TEE) to assess ASD morphology in more details, including the shunt and the length of anterior and posterior rim. If the posterior rim length was more than 5 mm, the patients underwent cardiac catheterization to study the hemodynamic and angiography. All catheterization procedures in adolescents were carried out under general anaesthesia whereas in adults, they were done with local anaesthesia and sedation.

All patients underwent cardiac catheterization of the right and the left heart. The sheaths were introduced into the right femoral artery, right femoral vein, and left femoral vein. Pressure and oxygen saturation (with 21% oxygen fraction) were taken from inferior vena cava (IVC), right atrium (RA), superior vena cava (SVC), right ventricle (RV), and pulmonary artery (PA) for the right-heart study and from the aorta, left ventricle (LV), and left atrium (LA) for the left-heart study. The flow ratio of pulmonary to systemic shunt was calculated. A pigtail diagnostic catheter was placed at the right pulmonary artery (RPA) for angiography to measure the size of ASD. If pulmonary pressure was more than 2/3 systemic pressure, the oxygen test procedure was performed by giving 100% oxygen with respect to reversibility of the pulmonary hypertension. In patients with low pulmonary to systemic flow and high pulmonary pressure after oxygen test, the Amplatzer® septal occluder was deployed at the ASD site for 20 minutes (occlusion test) and the pulmonary artery and right atrial pressures were observed. If the pulmonary artery and right atrial pressures were stable, the device was released. If the pulmonary pressure increased during the occlusion test, the device was withdrawn.

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Amplatzer® septal occluder was chosen for ASD closure, made from nitinol (nickel and titanium) wire mesh with retention discs on the left-side and right side, which were connected with a waist, so it resembles the letter of”H”. The nitinol wire mesh has a diameter of 0.004 inches. Inside the nitinol wire mesh, there are dacron layers which are favourable for thrombosis that will lead to ASD closure. The device is self-expandable and could be compressed under a catheter and can re-shape again after being deployed. It was designed to allow the discs to emerge at the ASD side. The device size was shown as the waist size. The left-sided disc retention width was 7 mm more than the device’s waist. The right-sided disc is slightly smaller than the left-sided disc. For ASD closure with this device, we need a delivery sheath or along sheath or a Mullin sheath, a delivery cable, a loading catheter, and a plastic versa.

Transesophageal echocardiography was performed in all patients to assess the ASD size and posterior rim length. After TEE, the defect size in stretch condition was confirmed with balloon sizing. The balloon was inflated until there was no flow across the defect (stop flow technique) and the waist was measured using the balloon marker. The device size was 2 mm larger than the streched diameter if the waist on balloon was clearly seen. If there was no anterior rim, the device size was 4 mm larger than the streched diameter. After balloon sizing, the balloon was withdrawn and the delivery sheath was introduced from right femoral vein to the left pulmonary vein with guidance of the Amplatzer® super-stiff wire. The dilator delivery sheath was withdrawn. The device was then screwed at the tip of the delivery cable and compressed inside the loading catheter. After that, it was introduced into the delivery sheath and the cable was pushed into the sheath. Using the fluoroscopy guidance, the delivery cable was advanced into the left atrium until the left atrial disc emerged and spontaneously reshaped. Then, the delivery system was withdrawn until the right atrium disc touch the atrium septum, then the sheath alone was withdrawn further over the delivery cable to allow the right atrial disc to emerge and reshape on the right atrial

side. Device position was assessed with TEE. If the device was not in a good position, it was retrieved into the delivery sheath and we re-deployed the device. If this procedure did not succed, we deployed the device using the left or right pulmonary vein assisted techniques. If these techniques also did not work, we cut the curve edge of the delivery sheath, leaving only the straight part. Using the RPV or LPV-assisted technique, the collapsed device was placed into the pulmonary vein, then the delivery sheath was withdrawn until the device was completely uncovered by the sheath. After this, the delivery cable was pushed to open the right disc, then by further pushing the cable, the left disc reshaped by itself after slipped out from the pulmonary vein. After the device was deployed at the atrium septum, blood flow in the pulmonary veins and mitral valve was assessed before the delivery cable was unscrewed to release the device. The stability of the device was then tested by gently pulling and pushing the cable several times. If the device was stable, we unscrewed the plactic versa counter clock-wise with fluoroscopy guidance until the device was released from the delivery cable. On the left anterior oblique 700 projection, RPA angiogram was performed to evaluate the shunt from LA to RA.

Patients underwent follow-up examinations, including chest radiography in antero-posterior (AP) and lateral positions and echocardiography to measure the pressure gradient across the tricuspid valve. Patient was given aspirin 5 mg/kg daily peroral for 6 months.

All data were processed using SPSS 17.0 version for Window. All data were expressed as mean (SD), or median and range.

RESULTSDuring the study period, 54 patients, of

whom 14 were adolescents (12-18 years-old) were referred for atrial septal defect closure. Baseline patients characteristics are shown in Table 1. Females outnumbered males by a ratio of almost 7:1. Most patients (59%) were within level I or II functional class.

Adolescent patients (14 patients, 26%) underwent catheterization intervention under general anesthesia while adults with local

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anaesthesia with sedation if necessary. The size of ASD was mostly large with a median of 26.4 mm. Median PA pressure after the procedure showed a little decrease compared to that before procedure. The majority (88%) of patients had a pulmonary artery pressure of less than two third of aortic pressure.

All patients underwent a transcatheter procedure and the ASD was closed by the Amplatzer® septal occluder as shown in Table 2.

The largest device used was the Amplatzer® device size number 38, whereas the most common size used were number 36 and 18 (8 patients each), followed by number 24 (7 patients). The remainders used number 20 and

22 (5 patients each), 28 (4 patients), number 26, 30, 32 and 34 (each in 3 patients), number 38 (2 patients), and number 14, 16 and 21 (each in 1 patient). The right pulmonary-assisted technique was the most common method used to deploy the device. A minority of patients (2%) used the cutting delivery sheath or left pulmonary assisted technique.

ASD closure by using Amplatzer® septal occluder was shown to be feasible and safe. The results are shown on Table 3. Most patients achieved complete closure immediately after the procedure, only around 5% who showed smoky residual shunt. The average length of the procedure is about 100 minutes.

Table 1. Patients’ characteristics

Variables Results

Age, median (range) years 30.1 (12-68)

Body weight, median (range) kg 49.1 (26-75)

Gender

- Male n(%) 7 (13)

- Female n(%) 47(87)

Clinical data

- Cephalgia n (%) 2 (4)

- Heart failure

- NYHA I n (%) 12 (22)

- NYHA II n (%) 34 (37)

- NYHA III n (%) 6 (11)

- NYHA IV n (%) 0 (0)

Electrocardiography

- RVH n (%) 24 (44)

- Normal QRS axis, n (%) 38 (70)

- RAD n (%) 16 (30)

Echocardiography

- ASD size (TTE) 21 (9.4-39.6)

- PG tricuspid valve (mmHg) 30 (23.8-44)

Catheterization data

- ASD (balloon sizing) 26.4 (14-38)

- PA pressure prior procedure (mmHg)

28.1 (11-74)

- PA pressure after procedure (mmHg)

27.5 (14-76)

- Flow ratio 3.1 (1.3-17.4)

- PARI 2.2 (SD 1.1)

ASD, atrial septal defect; NYHA, New York Heart Association; PARI, pulmonary artery resistance index; PA, pulmonary artery; PG, pressure gradient; RAD, right axis deviation; RVH; right ventricular hypertrophy; TTE, transthoracic echocardiography

Table 2. Device size and delivery techniques

Variables Results

Device size, median (range) mm 26 (14-38)

Balloon sizing, n (%) 54 (100)

Technique

Usual, n (%) 17 (31)

RPVAT, n (%) 35 (65)

PVAT, n (%) 1 (2)

Cutting delivery sheath, n (%) 1 (2)

Table 3. Amplatzer septal occluder results

Variables Results

Results ASO

- Complete closure n (%) 51 (87.9)

- Smoky residual n (%) 3 (5.2)

Fluoroscopy time 29.5 (18.1)

Procedure time 109 (36.7)

Complication

- Bradycardia n (%) 3 (6)

- SVT n (%) 2 (4)

Length hospital stay

- 1 day n(%) 44 (81)

- 2 days n(%) 9 (17)

- 3 days n (%) 1 (2)

ASO, Amplatzer® septal occluder; SVT, supraventricular tachycardia

No major complication was observed during the procedure. Transient bradycardia occurred in 3 patients and spontaneously-resolved SVT in 2 patients. Almost all patients were discharged

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from hospital on the next day after procedure and 9 were discharged on the second day. Only 1 patient was discharged on the third day because of heparinisation due to pulseless dorsalis pedis artery.

DISCUSSIONAtrial septal defects can be undetected until

adolesence or adulthood. The main problem in treating ASD in adults is pulmonary hypertension or even Eisenmenger syndrome.1,2 Traditionally, if a patient has Eisenmenger syndrome, it is contraindicated to close the ASD by either transcatheter procedures or surgery. But recently, with new techniques in transcatheter closure, we can perform an occlusion test to check whether PA and RA pressures increase by closing the ASD.17 If it happens, it means that the ASD itself is needed as a rescue to permit blood from right side of heart escaping to the left side because the blood may not be possible to go to the lung because of the very high resistance in the lung. Using the occlusion technique, if the PA and RA pressures increased after the ASD occlusion, we can retrieve the device again. In contrast, in surgical closure of ASD, surgeons are not able to do occlusion test because they work when the heart does not beat.3-6 If PH crisis happened after the surgical closing, the patch cannot be taken out and usually the patient will die. We performed an occlusion test in a patient who did not response to oxygen test. If there was no change in the PA and RA pressures after 20 minutes, we planned to release the device. In one case, we successfully released the devise without any change in PA or RA pressure. The symptoms of right heart failure disappeared and the patient can be discharged on the following day. Admosudigdo17 reported the success of using occlusion technique in all patients. Different from our study, he used balloon sizing to close the defect temporarily during testing.17 The disadvantage of this technique is that the inflated balloon is not stable and easily slips to RA. Moreover, the inflated balloon length is too long and sometimes it closes the pulmonary veins during the test, resulting in bradycardia.18 In this study we used the ASD device in the occlusion test in such a way that we deployed both disks in the ASD while it was

still attached to the cable in order to retrieve it in case a pulmonary crisis occurred.

Because of transcatheter closure of ASD needs TEE to evaluate the ASD and to confirm the position of the device before the release, we need cooperation of the patient. So, in adolescents the procedure was done under general anaesthesia. But in adults, we performed the procedure under local anaesthesia. If the patient was uncomfortable by the placement of TEE probe into his mouth, we gave sedation. In our series of 14 adolescents, we performed this procedure under general anesthesia, while in 40 adults, we performed the transcatheter closure using local anesthesia and sedation. Other study also reported similar procedures performed in various cardiac centers.7-16

Surgical closure of ASD in older adult has been found to be associated with significant mortality.3-6 Transcatheter closure ASD is significantly less invasive and results in less complications in older adults, including in patients with co-morbidities. In our 10 year experience, the transcatheter closure of ASD using Amplatzer® septal occluder were successfully attempted in 54 patients. The average age was 30.1 years old and the eldest patient was 68 years old. The presenting symptoms in adults were limited exercise capacity graded with NYHA functional class and cephalgia. Right ventricle hypertrophy was found in 44% patients and right axis QRS deviation was found in 30% of patients. The ASD size varied from 9.4-39.6 mm and the morphology led to different ways to approach the ASD. In our study we did not have serious complication like reported in other study.18-21

Technically, transcatheter closure of ASD in adults is easier compared to children. In children, there is a maximum size of the device that can be implanted. Using a size over maximum size will cause the device not open well into the heart chambers because the space is not enough. Some study reported that the maximum device that can be used in children is less than or maximally equal to the left atrial systolic dimension (LASD) minus 14 mm. If the required device is larger than maximal size possible for the child, we cannot close it transcatheterly and we send the patient to the surgeon. In adults, we can use the

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largest size that is available, such as size number 38 mm or even 40 mm without any difficulty. In adults, we can close all secundum ASD as long as the posterior rim is sufficient, which is at least of 7 mm length. Eventhough a patient has no sufficient anterior rim, if the posterior rim presents, we still can close the ASD by transcatheter technique. In our series, all of the patients underwent transcatheter closure of ASD successfully.

The technique that we tried initially is the common technique. Using this technique, we opened first the left side of the device in the left atrium, and then we withdrew all the system until the left disk touched the atrial septum, followed by withdrawing the sheath to open the right disk. This technique only succeeded in 17/54 (31%) patients with ASD of less than 20 mm. In large ASD (more than 20 mm) during the deployment the right disk, the left disk will prolapse into the right atrium because the right disk will be opened by pulling the left disk to the right atrium.22,23 They reported that to overcome prolapse of the left disk into the right atrium, he used another technique, such as right or left pulmonary assisted techniques or by using a straight delivery sheath.22,23 By right or left pulmonary vein technique we open the collapse left disk inside the pulmonary vein, followed by pulling the delivery sheath until the collapsed device being uncovered out of the sheath and then we push the delivery cable to open up the right disk first. By further pushing of the cable, the left disk will open by itself after it slipped out from the pulmonary vein. He reported that all of his patients who failed with common technique have success closures using this technique. In our series, we successfully implanted the device using the right pulmonary vein technique in 35/54 (65%) patient and the left pulmonary vein technique in 1/54 (2%). In 1/54 (2%) patient, after trying all the described techniques above, the device still prolapsed into the right atrium. We finally used the last technique using a straight delivery sheath by cutting the curve of the delivery sheath, leaving its straight. As an alternative to the cutted long delivery sheath, we can use steerable long delivery sheath (Fustar®). Literatures mentioned

successful results of closing of large ASDs using the steerable long sheath.22,23

To choose the device to be implanted, some experts did not use balloon sizing anymore.24 But in this study, we still use balloon sizing in all patients. We inflated the balloon until the flow through the ASD stops as monitored using the TEE (the stop-flow technique). If the waist of the balloon is seen clearly, the measured ASD size is 2 mm above the waist diameter, but if the waist is not clearly seen, we add at least 4 mm to the waist diameter. The disadvantage of not using balloon sizing is that we overestimate or underestimate the appropriate device size. If the size is not appropriate, we have to take another new device. Because the price of device is expensive, so we should avoid this mistake. If we used oversize device, it will cause erosion of the atrial wall and the patient may suffer from cardiac tamponade and urgent surgery must be done as reported by some study.19,20

The co-morbidities of our series of case mostly were mild pulmonary hypertension but on the catheterization, the Qp:Qs ratio was around 3.1 with pulmonary arterial resistance index was 2.2. We only had one patient with severe pulmonary hypertension. Symptomatic improvement was observed in all patients and most of the patients were discharged on the next day after the procedure. Advanced modalities and interventions for ASD closure should be considered once the diagnostic is established, irrespective of age.7-16

CONCLUSIONTranscatheter ASD closure using Amplatzer

septal occluder can be safely performed at any age from adolescents to adults. Problems in these age group are pulmonary hypertension or arrhythmias. The difficulties of the ASD morphology where its size and position and the need to modified techniques to deploy the device. Being significantly less invasive, transcatheter closures using the Amplatzer® septal occluders are associated with fewer complications especially in older adults with the possibility of pulmonary hypertension. The best outcome is achieved in patients with less functional impairment and less elevated

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PA pressure. Morbidity is low and the patients usually can be discharged from the hospital within 24 hours after the procedure.

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