Intervention challenges in patients with congenital heart disease with coexisting interruption of the inferior vena cava - A case series :Saurabhi Das, Mahua Roy, Amitabh Chattopadhya, Debasree Ganguly, Heart Views

CASE REPORT
Year : 2021 | Volume : 22 | Issue : 3 | Page : 224--230

Intervention challenges in patients with congenital heart disease with coexisting interruption of the inferior vena cava - A case series

Saurabhi Das¹, Mahua Roy¹, Amitabh Chattopadhya², Debasree Ganguly¹,
¹ Department of Paediatric Cardiology, Rabindranath Tagore International Institute of Cardiac Sciences, Kolkata, India
² Department of Paediatric Cardiology, Narayana Super Speciality Hospital, Howrah, West Bengal, India

Correspondence Address:
Dr. Saurabhi Das
Department of Paediatric Cardiology, Rabindranath Tagore International Institute of Cardiac Sciences, Mukundapur Market, Stadium Colony, Mukundapur, Kolkata - 700 099, West Bengal
India

Abstract

Interruption of the inferior vena cava with azygos continuation is a rare congenital anomaly. This anomaly becomes clinically important during cardiac interventions.

How to cite this article:
Das S, Roy M, Chattopadhya A, Ganguly D. Intervention challenges in patients with congenital heart disease with coexisting interruption of the inferior vena cava - A case series.Heart Views 2021;22:224-230

How to cite this URL:
Das S, Roy M, Chattopadhya A, Ganguly D. Intervention challenges in patients with congenital heart disease with coexisting interruption of the inferior vena cava - A case series. Heart Views [serial online] 2021 [cited 2023 Dec 8 ];22:224-230
Available from: https://www.heartviews.org/text.asp?2021/22/3/224/328020

Full Text

Introduction

Interruption of the inferior vena cava (IVC) with azygos continuation is a rare congenital anomaly. In this condition, the IVC is interrupted below the hepatic vein and venous return beyond this point is re-established by the dilated azygos and hemiazygos veins draining into the superior vena cava (SVC).[1] Isolated congenital anomalies of IVC are rarely reported. The incidence of this anomaly approximates 0.6% in patients with congenital heart defects.[2] Interruption of IVC with well-developed azygos or hemiazygos continuation often goes undiagnosed due to lack of physiologic abnormality.

This anomaly becomes clinically important during catheterization, transcatheter interventions, radiofrequency ablation, and planning of surgery in heterotaxy patients. Moreover, the venous approach to the heart becomes difficult in interrupted IVC, mainly due to the acute angulation at the azygos–SVC junction.[3]

There is lack of data on the unique challenges, technical issues, and complications and mid-to-long–term outcomes in these patients managed by transcutaneous interventions. Here, we described a case series of eight patients diagnosed with interrupted IVC and managed through various transcatheter interventions at Department of Paediatric Cardiology, Rabindranath Tagore International Institute of Cardiac Sciences, Kolkata, India.

Case Presentation

Patient 1

A 6-year-old male child weighing 20 kg presented for the evaluation of his incidental heart murmur. The patient was found to have mild cardiomegaly with right ventricular (RV) type of apex, prominent "a" waves in jugular venous pressure (JVP), and systolic thrill on left second intercostal space (ICS) present on palpation. On auscultation, fixed wide S2 split and a Grade 4/6 ejection systolic murmur at the second left ICS up to left supraclavicular region along with a prominent ejection click were present.

Electrocardiogram (ECG) showed sinus rhythm with an incomplete right bundle branch block. Chest X-ray (CXR) revealed mild cardiomegaly with RV apex, normal pulmonary vascular markings, and prominent main pulmonary artery (PA) segment. Transthoracic echocardiography (TTE) detected a 14 mm × 10 mm ostium secundum atrial septal defect with adequate rims all around and systolic doming of pulmonary valve (PV) with severe stenosis (gradient of 75 mmHg). PV annulus was 15 mm. Right atrium (RA) and RV were dilated and mild tricuspid regurgitation (TR) was present.

Initially, we planned simultaneous transcatheter closure of ASD with balloon pulmonary valvuloplasty (BPV). However, we diagnosed an IVC interruption with azygos continuity in the preprocedure echocardiography in the catheterization laboratory. Hence, we opted for right internal jugular venous (RIJV) route and placed a 5 F short sheath (Terumo®) along with 2000 U of intravenous heparin. We also introduced a 5 F NIH catheter through the same route and kept it in RV apex (RIJV–SVC–RA–RV).

An angiogram was done in anteroposterior (AP) and shallow left anterior oblique projection (LAO) cranial view to delineate the stenotic PV. The PV annulus was 15 mm. We used a Cobra catheter (Terumo®) to cross the stenotic PV with a straight tip (0.032 inch × 260 cm) glide wire (Terumo®) and kept it in the left PA (LPA) (RIJV–SVC–RA–RV–PV–LPA). The PA pressure was 21/16/20 mmHg and the peak systolic gradient across the PV was 54 mmHg. Then, we kept a 0.032 inch × 260 J tip Teflon wire (Cordis Corp., Florida, USA) in the LPA and passed a 16 mm × 40 mm Tyshak II® balloon catheter over the wire and inflated until the full disappearance of waist. We took out the balloon and put the same Cobra catheter across the PV again. The pullback gradient came down to from 54 to 14 mmHg. Then, we introduced 5 Fr right coronary artery catheter (Medtronic Inc.,) with a hydrophilic guide wire through the ASD into the LA. We tried to keep it in one of the pulmonary veins but failed even after repeated attempts. We obtained a stable position in the LA just in front of mitral valve (MV). We also kept a 0.035 inch × 260 cm Amplatz extra-stiff guide wire (Cook Medical Inc., Bloomington, IN, USA) in the same place and a 9 Fr delivery sheath (St. Jude Medical, St Paul, MN, USA) with dilator was advanced with great care. The dilator was removed with the check flow of the sheath under water to prevent air embolism.

Under TTE and fluoroscopic guidance, we passed a 16-mm Amplatzer® atrial septal occluder (ASO) (St. Jude Medical, St Paul, MN, USA) device through the delivery catheter without exiting from the tip of the sheath. Then, we withdrew the whole system into the LA cavity and placed the tip of sheath above the MV. The left disc of the device was unsheathed within the LA and gently pulled against the interatrial septum. With gentle tension on the delivery system, we pulled back the sheath and opened the right atrial disc. We then positioned the device parallel to the septum. Control transesophageal echocardiography demonstrated a stable occluder device with cessation of the interatrial shunt, and the procedure was completed without any complications. The child is doing well on follow-up for the last 7 years.

Patient 2

This was a referred case of an incidental murmur in a 9-year-old female child, weighing 15 kg. Echo revealed IVC, 3 mm patent ductus arteriosus (PDA) with left-to-right shunt, peak gradient of 88 mmHg, and dilated LA and left ventricle (LV).

Initially, the patient was planned for PDA device closure. The access was made from the RIJV with 5F radial sheath. We passed a Judkin's right heart coronary catheter (5 F) over J tip 0.025 inch exchange length guide wire (Terumo®) from right IJV to main PA past the RA and RV and directed into the PA. We exchanged the 0.025 inch wire with extra stiff Amplatz wire (AGA Medical Corp, Golden Valley, MN, USA). A 6 Fr delivery sheath was advanced over the super stiff wire and placed in the descending aorta with almost 90° curve from RA to PA and another acute curve of 30°–40° from PA to aorta. Positioning or advancing the device across the sheath went smoothly. A 6/4 mm Amplatzer duct occluder (ADO) device was passed through the delivery sheath and aortic end opened in the descending aorta, and gradually, the device was successfully deployed across the PDA. There was minor intradevice leak, which subsided after 12 h [Table 1]. The child was doing well on follow-up [Figure 1].{Table 1}{Figure 1}

Patient 3

A 5-year-old female child presented with complaints of tachypnea, failure to gain weight, and recurrent lung infections. On palpation, cardiomegaly, LV apex, prominent A wave in JVP, systolic thrill present on the second ICS of both sides. On auscultation, S2 split and a Grade 3/6 continuous murmur at the second left ICS up to left supraclavicular region were present.

ECG showed normal sinus rhythm with normal axis and LV dominance. CXR revealed cardiomegaly with prominent pulmonary vascular markings and prominent main PA segment. TTE performed at the out patient department showed a 4mm moderate PDA with moderate pulmonary stenosis (PS) with a peak gradient 48mm Hg, a 16mm PV annulus , a bicuspid aortic valve with severe aortic stenosis (AS) with a peak/mean gradient of 72/48 mm Hg, a 14 mm AV annulus , and an interrupted IVC with azygos continuation.

There was LV hypertrophy with an ejection fraction of 72%. The posterior wall thickness to the ventricular septal thickness was 16 mm/14 mm.

We planned to do device closure of the PDA along with balloon aortic valvuloplasty (BAV) and percutaneous balloon pulmonary valvuloplasty (BPV) after consent. We took three access: the right internal jugular vein (RIJV) venography access, the right femoral vein, and the right femoral arterial access. We planned to do BAV first, followed by the BPV and finally device closure of the duct.

An ascending aortic pressure showed a systolic pressure gradient of 110 mmHg. The valve was crossed with a 0.025 inch straight tip Terumo® wire on a 5 Fr Judkins right catheter. After parking the Judkins right in the LV, we took the LV systolic pressure, which came out to be 57 mmHg systolic and a gradient of 53 mmHg across the valve was obtained. The Terumo® wire was exchanged for a 0.25 inch amplatzer super stiff wire and a 14 mm × 20 mm Tyshak II balloon was positioned across the valve. A temporary pace maker(TP) was passed through the RIJV route and was placed in the RV before inflating the balloon. The RIJV route was used because of the presence of interruption.

The BAV was done successfully under temporary pacing. This was followed by BPV where the PV was crossed from the RIJV to RA to RV to PA. A 5 Fr Judkins right catheter over a 0.025 inch straight tip Terumo® wire was used to cross the PV. The 0.025 inch Amplatzer super stiff wire was parked in LPA and valvuloplasty was successfully done using an 18 mm × 40 mm Tyshak II balloon. Finally, the patent ductus was closed through the retrograde route using a 5/4 ADO II device [Figure 2].{Figure 2}

Patient 4

A 7 month-old infant weighing 5.5 Kg was diagnosed with moderate PDA(4 mm) and interrupted IVC without pulmonary arterial hypertension(PAH). We made both right femoral venous and right femoral arterial access and found interruption of the IVC with azygous continuation. An aortic angiogram subsequently detected a 4-mm PDA. Under fluoroscopic guidance, we closed the ductus with a 5/4 ADOII device using a 5 Fr guiding Judkins catheter through retrograde approach. Postprocedure angiogram showed complete closure of the ductus.

Patient 5

An 8-year-old boy presented with complaints of easy fatigability. We found a precordial bulge and a continuous murmur was heard over the left second ICS on clinical examination. Echo showed a moderate size PDA (4 mm), interrupted IVC with hemiazygous continuation, and no PAH.

We planned for a transcatheter device closure through IVC–azygous route. We crossed the PDA by 5 F multipurpose catheter (MP catheter) and a J tip 0.025-Terumo® wire. We passed a super stiff wire through MP catheter and snared through the femoral arterial route to form an arteriovenous loop and put a 6 Fr Amplatzer delivery sheath over it. This was a difficult track for a delivery sheath, passing at two angulations, first at azygous–SVC junction and second at RV outflow tract to PDA; however, due to the arteriovenous loop, the sheath was smoothly positioned into descending aorta. Then, we passed an 8/6 mm device through the delivery sheath and its aortic end opened in the descending aorta. While pulling the delivery system from the descending aorta to the PDA, the control was low due to a curve at IVC–azygous route with stretching of RA, leading to transient bradycardia. We waited for 10 min until the vitals stabilized and then successfully deployed the PDA device under fluoroscopy via RIJV. We kept the child under observation for 24 h postprocedure and then discharged with no postoperative complications.

Three patients (6–8)

A 9-month-old male, 7-month-old female, and 2–year-old male with 9 kg, 6.5 kg, and 10 kg weights, respectively, presented with complaints of recurrent lower respiratory infection and murmur on cardiac auscultation. All three of them had moderate-sized PDA (3 mm), dilated left-sided cardiac chambers, and no PAH on echocardiography.

We planned transcatheter duct closure for all the three patients. The device selection is based on patent ductus arteriosus size [Table 1]. In the first two cases, we diagnosed IVC interruption on the table after recurrent failures to pass catheter directly into RA. We proceeded with percutaneous closure of PDA using an ADO II through a retrograde approach in all of these three cases. We placed one 5 Fr sheath in the right femoral vein and another in the right femoral artery.

A contrast injection in the IVC showed an interrupted IVC with azygos continuation draining to the SVC. A descending aortogram was performed with a 5 Fr pigtail catheter (Cook, Bloomington, USA) showed a Krichenko Type A PDA of 3 mm at pulmonary end and 6 mm at the ampulla.

Hemodynamic data showed a Qp/Qs of 1.5, 1.9, and 1.4 in the 6, 7, and 8 case, respectively, and all the three patients' pulmonary pressure were within normal limits. We followed similar procedure of intervention in all three cases. First, we crossed the PDA with a 5 F Judkins right catheter (Cordis, Minneapolis, MN, USA) and a 0.025 inch × 260 exchange length Terumo® wire. We parked the wire in the RV and followed by the removal of the catheter. We advanced a 5 F TorqVue low profile delivery catheter (AGA Medical, Golden Valley, MN, USA) over the wire from the descending aorta into the PA.

We occluded the PDAs with ADO II 6 mm × 6 mm device screwed onto the delivery cable and pushed through the delivery catheter. Postprocedure angiogram showed complete closure of the ductus in all three cases.

Discussion

Interruption of the IVC is a relatively rare abnormality with an estimated incidence of 1 in 5,000 cases.[4] Developmentally, IVC is formed during 6th–8th weeks of gestation. When the union between the hepatic and prerenal segments fails during embryologic development, "intrahepatic interruption of the IVC with azygos continuation" happens. As a result, blood shunts from the supra-subcardinal anastomosis through the mildly dilated retrocrural azygos vein.[1],[5]

Different percutaneous interventions in patients with IVC interruption have been described by various literatures. In this series of cases with interrupted IVC treated through various interventions, we like to highlight the challenges faced during procedures and our management methods. Commonly available devices, delivery systems and balloon catheters for percutaneous device closure, balloon dilatation of valve, and placement of temporary pacemaker lead are designed to be used through the femoral venous route.

However, in interrupted IVC, this classical, time-tested route cannot be utilized. Open-heart surgery (OHS) is opted even for these "simple defects" which are otherwise amenable to transcatheter intervention. The limitations associated with OHS justify exploring alternative route for intervention in interrupted IVC patients. There are many alternative approaches for ASD device closure in interrupted IVC patients such as (1) through IJV approach (RIJV–SVC–RA–ASD–LA), (2) azygos continuation route (femoral vein–intrahepatic IVC–azygos vein-RA–LA) or (3) transhepatic route (hepatic vein–RA–ASD–LA).[6]

We used RIJV route for ASD device closure along with BPV for Patient 1 and along with BAV and BPV in Patient 3. For PDA device closure we had used RIJV for Patient 2. For Patient 5 where azygos vein was dilated and capcious, we had chosen azygos continuation route. For patients 4, 6, 7, and 8, PDA closure was done by retrograde approach.

Transjugular venous access for ASD device closure is well described in the literature.[7]

Ozbarlas et al. published the first report of the use of IJV access to device closure of ASD in a child with heterotaxia and interrupted IVC.[8] Kumar et al. reported that RIJV route was advantageous over femoral route in presence of septal malalignment. RIJV approach perhaps helped successful device closure in postoperative residual ASD, which was associated with septal malalignment.[9]

Percutaneous ASD device closure by RIJV approach was also reported in elderly patient, in whom routine femoral venous approach was not feasible because of severe scoliosis.[10]

In our first case in the series (Patient 1) with ASD and severe PS, we opted for transjugular approach and successfully completed ASD device closure and BPV. Most reports mentioned previously,[8],[9],[10] where RIJV access was used, had shown that manipulating and maintaining a stable wire position into the pulmonary vein was very difficult. The most challenging part was deployment of the device from the sheath pointed toward the LV inflow (MV) or left atrial appendage.

Similarly, we also faced this particular problem in our Patient 1 and failed to keep sheath in any of the pulmonary veins. Finally, we crossed MV to have had a stable wire and delivery sheath position. A similar technique of device deployment was mentioned by Xu et al.[11] The likelihood of damage of the MV and subvalvar apparatus is high in this technique, and great care should be taken while manipulating delivery system or device close to LV inflow. There is also marginally increased risk of air embolism in this route. The risk of air embolism can be negated by the underwater technique of removal of dilator from the sheath.[9]

IJV approach had been reported to be used for BPV in PS and crossing of stenotic PV was consistently easy and quick with this route.[12] We had a contradictory experience in Patient 1 where we failed to cross PV with different catheters on repetitive attempts. We used RIJV–RA–RV–PV route and chose Cobra catheter along with straight tip exchange length glide wire, which ultimately crossed stenotic PV.

Our second patient was diagnosed with PDA and the closure was done through RIJV route. There was no major challenge except a minor intradevice leak which subsided after 12 h.

Our third patient was unique that child had moderate PS and severe AS with moderate PDA. But each lesion was amenable to the intervention. We planned BAV, BPV, and PDA device closure. For BAV, we needed a stable balloon and wire position that could be achieved by either rapid ventricular pacing or adenosine administration.

As per the institutional protocol, we were more comfortable with rapid RV pacing rather than IV adenosine. We introduced temporary pacing wire from RIJV route instead of femoral vein with excellent outcome. Hajizadeh et al.[13] reported a 75-year-old patient with complete heart block where they had introduced temporary pacing wire through hemiazygos continuation route with great difficulties. However, we did not have similar experience. After BAV, we did BPV by same RIJV route and at last PDA device closure by retrograde aortic approach with ADO II device.

Percutaneous PDA device closure via the azygos route is an alternate known option. The challenges with this route are kinking of catheters, failure to advancing the delivery sheath, and kinking at the acute angle of azygos–SVC junction and RV outflow tract. There is undue stretch at azygos–SVC level while pulling the delivery sheath across PDA. Agarwal et al stated that it is extremely difficult to take two 180°curvatures in the azygos route. Glide wire and MP catheter may be negotiated, but manipulating device delivery system was extremely difficult. According to that report, it is better to do by RIJV route rather than azygous. The success of our case was due to the following factors: (1) The SVC was spacious in caliber. (2) Snaring of super-stiff Amplatzer wire and making one stable arteriovenous loop so that delivery system can take two 180° turn smoothly.[3],[14]

In our present case series, Patient 5 was managed by PDA device closure through azygos continuation route, but our experience of ASD device closure by similar approach is lacking.

Another possible route for PDA device closure is retrograde aortic approach. This is well described in interrupted IVC patient. By this approach, manipulating delivery system through azygos route or RIJV can be avoided.[3] We used this route in four patients (4 and 6–8) and did PDA closure by ADO II device.

ADO II is a self-expanding multi-layer device with nitinol wire braid. It has two symmetric retention discs and one articulating connecting center waist. The discs are 6 mm larger than the diameter of the connecting waist. There is no sewn-in polyester fabric in the device and is low profile. The connecting waist diameter is between 3 and 6 mm and its length is available in 4 and 6 mm. The initial experience in children using ADO II for small and moderate-to-large PDAs was promising as reported by Thanopoulos. The device is highly effective in occluding PDAs of wide variety of sizes.

ADO II device can cause aortic and LPA obstruction in smaller kids. Moreover, the device cannot be used with large PDAs. Amplatzer vascular plugs and septal occluders have also been used in PDA closure due to the considerable variation in the shape and size of PDAs.[15],[16]

In the published literature on alternate routes used for PDA closure, Akhtar et al.[17] mentioned using a RIJV approach in a patient with interrupted IVC and blood flow directed to a hepatic venous plexus whereas Sivakumar and Francis[18] reported having PDA closure through retrograde approach from the aorta with a reversed device position, the aortic disc facing the PA and the tubular end facing the aorta. Koh et al. used the transarterial approach but with an ADO II device.[3]

Another alternative route is a transhepatic approach, which is in use for a long time for venous access in the pediatric patients. The advantages of this route are the large caliber of hepatic veins and the inferior approach that makes sheath placement optimal and catheter stability better, respectively. The complication rate of transhepatic approach in cardiac procedures as <5% in a pediatric population. However, the cardiologist needs to be careful to avoid complications such as abdominal bleeding, peritonitis, perforation of the gallbladder, thrombosis of portal vein, liver injury, and pneumothorax.[19]

Conclusion

Isolated interrupted IVC is often clinically asymptomatic. Cardiologists have to use alternate routes to reach the right heart for cardiac procedures in these cases.

Our experience of using various routes [Table 2] beyond standard femoral access for managing congenital cardiac defects with concomitant interrupted IVC was technically challenging, but we were successful because of meticulous planning and seeking feasible alternate techniques wherever needed.{Table 2}

Technical challenges are imperative in alternative route for device closure or BPV or TP independently or in combination in patients with interruption. To our knowledge, procedures are reported in isolated cardiac defects through alternate routes but rare in combination such as ASD and BPV in a same patient or PDA and BPV with BAV along with TP in interrupted IVC patient in the published literature.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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