Staged Transcatheter Treatment of Portal Hypoplasia and Congenital Portosystemic Shunts in Children

Novel Staged Device Occlusion of Portosystemic Shunt With Atrial Flow Regulator in IVC Stent Platform

We present the cases of 2 children diagnosed with extrahepatic portosystemic shunts, a very rare vascular anomaly, on investigation of cardiac symptomatology. Poorly developed portal venous systems necessitated staged shunt occlusion. This was achieved using atrial flow regulator devices positioned in an inferior vena cava stent platform performed in the cardiac catheterization laboratory.

Off-label use of muscular VSD device for closure of a rare congenital portosystemic shunt

BACKGROUND

Congenital portosystemic shunt (CPSS) is a vascular malformation in which portal blood drains toward the systemic circulation, leading to pulmonary hypertension.

CASE PRESENTATION

A 10-year-old patient was brought for evaluation because of dyspnea on exertion. Echocardiography revealed a pulmonary hypertension of 75 mmHg, and multi-slice CT angiography revealed the presence of a CPSS. Closure was finally implemented using a muscular ventricular septal defect device. Follow-up of the patient revealed a gradual decline in pulmonary hypertension.

CONCLUSIONS

CPSS is an overlooked cause of reversible pulmonary hypertension (PH). Closure of such lesions and reversal pulmonary hypertension are possible via catheterization. The preferred device type depends largely on the intervening team. Plugs are the first choice for interventional radiologists, while ventricular and atrial septal occluder devices and duct occluders are preferred by pediatric cardiologists.

Expert management of congenital portosystemic shunts and their complications

Congenital portosystemic shunts are often associated with systemic complications, the most challenging of which are liver nodules, pulmonary hypertension, endocrine abnormalities, and neurocognitive dysfunction. In the present paper, we offer expert clinical guidance on the management of liver nodules, pulmonary hypertension, and endocrine abnormalities, and we make recommendations regarding shunt closure and follow-up.

Embolization in Pediatric Patients: A Comprehensive Review of Indications, Procedures, and Clinical Outcomes

Embolization in pediatric patients encompasses a large spectrum of indications, ranging from the elective treatment of congenital diseases of the cardiovascular system to the urgent management of acute hemorrhagic conditions. In particular, the endovascular treatment of central and peripheral vascular malformations and hypervascular tumors represents a wide chapter for both congenital and acquired situations. Thanks to the progressive availability of low-profile endovascular devices and new embolic materials, the mini-invasive approach has gradually overtaken surgery. In this review, the main embolization procedures will be illustrated and discussed, with a focus on clinical indications and expected outcomes. The most recent mini-invasive techniques will be described, with hints on the cutting-edge devices and embolic materials.

Endovascular Treatment of Congenital Portosystemic Shunt: A Single-Center Prospective Study

PURPOSE

To design a prospective study on endovascular closure of congenital portosystemic shunts. The primary endpoint was to assess the safety of endovascular closure. The secondary endpoint was to evaluate the clinical, analytical and imaging outcomes of treatment.

METHODS

Fifteen patients (age range: 2 days to 21 years; 10 male) were referred to our center due to congenital portosystemic shunts. The following data were collected prior to treatment: age, sex, medical history, clinical and analytical data, urine trimethylaminuria, abdominal-US, and body-CT. The following data were collected at the time of intervention: anatomical and hemodynamic characteristics of the shunts, device used, and closure success. The following data were collected at various post-intervention time points: during hospital stay (to confirm shunt closure and detect complications) and at one year after (for clinical, analytical, and imaging purposes).

RESULTS

The treatment was successful in 12 participants, migration of the device was observed in two, while acute splanchnic thrombosis was observed in one. Off-label devices were used in attempting to close the side-to-side shunts, and success was achieved using Amplatzer^™ Ductus-Occluder and Amplatzer^™ Muscular-Vascular-Septal-Defect-Occluder. The main changes were: increased prothrombin activity (p=0.043); decreased AST, ALT, GGT, and bilirubin (p=0.007, p=0.056, p=0.036, p=0.013); thrombocytopenia resolution (p=0.131); expansion of portal veins (p=0.005); normalization of Doppler portal flow (100%); regression of liver nodules (p=0.001); ammonia normalization (p=0.003); and disappearance of trimethylaminuria (p=0.285).

CONCLUSION

Endovascular closure is effective. Our results support the indication of endovascular closure for side-to-side shunts and for cases of congenital absence of portal vein.

A new variant of Abernethy malformation treated by transhepatic interventional closure: a case report

Background

Congenital portosystemic shunts (CPSS) are rare vascular malformations and can be classified into extrahepatic and intrahepatic shunts. Extrahepatic CPSS, also termed Abernethy malformations are associated with severe long-term complications including portopulmonary hypertension, liver atrophy, hyperammoniemia and hepatic encephalopathy. We report a hitherto undescribed variant of Abernethy malformation requiring an innovative approach for interventional treatment.

Case presentation

We describe a 31-year-old patient following surgical repair of atrioventricular septal defect at the age of 6 years. In the long-term follow-up he showed persistent pulmonary hypertension which deteriorated despite dual pulmonary vasodilative treatment. When he developed arterial desaturation and symptomatic hyperammoniemia detailed reassessment revealed as underlying cause a hitherto undescribed variant of Abernethy malformation connecting the portal vein with the right lower pulmonary vein. Following interdisciplinary discussions we opted for an interventional approach. Since the malformation was un-accessible to interventional closure via antegrade venous or retrograde arterial access, a transhepatic percutaneous puncture of the portal vein was performed. Temporary balloon occlusion of the malformation revealed only a slight increase in portal venous pressure. Interventional occlusion of the large vascular connection was achieved via this transhepatic approach by successive implantation of two large vascular occluding devices. The postinterventional course was unremarkable and both ammonia levels and arterial saturation normalized at follow-up of 12 months.

Conclusions

Portal vein anomalies should be included in the differential diagnoses of pulmonary hypertension or pulmonary arterio-venous malformations. Based on careful assessment of the anatomy and testing of portal vein hemodynamics interventional therapy of complex Abernethy malformations can be performed successfully in specialized centers.

Transcatheter closure of congenital portosystemic shunts – A multicenter experience

Background:

Congenital portosystemic shunts (CPSS) are rare and present variably with hepatic encephalopathy, pulmonary arteriovenous malformations (PAVMs), and pulmonary hypertension (PH).

Objective:

The objective of the study was to see the feasibility of transcatheter closure of CPSS and their outcome.

Materials and Methods:

We analyzed the data of 24 patients of CPSS who underwent transcatheter closure from five institutions (March 2013 to April 2019). Baseline evaluation included echocardiography with bubble contrast study, ultrasound examination of the abdomen, computed tomography angiogram, and cardiac catheterization with test balloon occlusion of the CPSS. The evaluation showed cyanosis due to PAVM in 12, PH in 8, and respiratory distress in 2. Two had both cyanosis and PH. Criteria for eligibility for complete catheter closure of CPSS included demonstration of intrahepatic portal vein (PV) radicals together with a PV pressure of ≤18 mmHg on occlusion.

Results:

The median age and weight were 8 years (0.5–21) and 19.5 kg (4.2–73), respectively. Transcatheter closure was performed in 21 patients (22 procedures) using a variety of occlusive devices and stent-graft exclusion was done in one patient. Closure was not done in 3 in view of high portal venous pressures and hypoplastic PVs. During the follow-up (median: 42 months and range: 61 days–4.8 years), saturation normalized in 14 patients with PAVM. PH declined in all eight patients who underwent the procedure. Respiratory distress improved in two patients.

Conclusions:

Early and short-term follow-up results of catheter closure of CPSS appear promising. However, further, follow-up is needed to demonstrate long-term effectiveness.

Percutaneous treatment of a huge patent ductus venosus and severe portal vein hypoplasia using a Figulla Flex II atrial septal defect occluder in a 2-year-old infant: a case report

Background

Intra- or extrahepatic porto-caval shunts (PCSs) can account for multiorgan dysfunction with pulmonary arterial hypertension and portosystemic encephalopathy as the most serious consequences of bypass of the hepatic circulation. The ductus venosus (DV) represents a rare foetal PCS and might be persistently patent in newborns after birth. Treatment strategies include surgical ligation and percutaneous device closure. The degree of portal vein hypoplasia limits therapy making liver transplantation the only option in some of them.

Case summary

In a newborn female patient a huge persistently patent DV, known already prenatally, resulted in severe secondary portal vein hypoplasia. She presented with hyperammonaemia, elevated liver enzymes, and pulmonary hypertension. With only diminutive portal venous branches and exceedingly high portal venous pressures during test-occlusion of the DV, shunt closure was not possible. At the age of 2 years more favourable portal venous pressures allowed transcatheter device closure with a nitinol atrial septal defect occlusion device. Pulmonary artery pressures and ammonia levels normalized after the procedure without any signs of portal hypertension.

Discussion

The case highlights the importance of meticulous imaging using balloon occlusion angiography of PCSs like the DV, to search for intrahepatic portal veins. Moreover, portal vein pressure during test-occlusion can identify patients amenable for surgical or endovascular shunt closure. Occlusion devices licensed for other indications like atrial septal defect closure can be used safely in huge PCS vessels in a one-step or staged procedure. Optimal timing of the intervention should be tailored to the patient’s needs

Restriction of congenital portosystemic shunt using the modified microvascular plug

Congenital portosystemic shunts (CPSS) may produce a variety of severe, clinically detrimental presentations. When indicated, closure is recommended; however, if the intrahepatic portal venous system (IPVS) is underdeveloped complete closure may not be possible and may result in severe acute portal hypertension. Staged restriction of CPSS flow by both surgical and complex transcatheter interventions has been successful in augmenting development of the IPVS such that complete occlusion of the CPSS can be performed. We report use of a modified microvascular plug to restrict CPSS flow with subsequent IPVS development and safe complete occlusion of CPSS.

Multistage closure of a congenital extrahepatic portosystemic shunt

Background

Congenital extrahepatic portosystemic shunts (CEPS) are rare shunts connecting the extrahepatic portal system with the inferior vena cava. Shunt dimensions and the risk of portal hypertension determines the closure strategy. Endovascular treatment is indicated for single stage occlusion of longer length shunts, whereas the remaining shunt types are preferentially surgically occluded. Herein we describe the technical details of a novel endovascular treatment for short length CEPS.

Case presentation

A 15-years-old male with a short length CEPS complicated with multinodular liver disease was submitted to a multistage closure, as indicated by the high portal pressure values during shunt balloon occlusion venography. Initially a transjugular intrahepatic portosystemic shunt (TIPS) was created and the CEPS occluded with an atrial septal defect occluder. In a second procedure the TIPS was embolized with a flow reductor stent and an amplatzer vascular plug II. At a 1 year follow up the liver nodules size reduced, the patient remains asymptomatic, and the shunt adequately closed.

Conclusion

This paper outlines the potential use of a TIPS and an atrial septal defect occluder combination in complex CEPS, supporting its usage as an alternative to the standard surgical treatment.

Level of Evidence: Level 4, Case report.

Novel transcatheter treatment for staged closure of Abernethy malformation with portal hypoplasia

Portosystemic shunts are rare congenital malformations that come to attention due to various hepatic and extrahepatic manifestations. Management of this malformation is dictated by the presence and adequacy of intrahepatic portal radicals. Staged occlusion of the shunt is recommended in patients with severely hypoplastic portal radicals. We describe a novel transcatheter technique that we improvised for staged occlusion of Abernethy malformation in a 2-year-old girl.

Congenital absence of the portal vein: Define the portosystemic shunt, avoid liver transplantation

Liver transplantation has been historically recommended for patients with congenital absence of the portal vein associated with extrahepatic congenital portosystemic shunts. Here, based on a case report of a 2-year-old girl and a thorough review of all published cases from 1974 to 2020, we show that such a diagnosis most often conceals a hypoplastic portal vein, which can be successfully re-permeabilized through the closure of the shunt in order to re-establish a physiological vascular anatomy. This highlights the importance of achieving a detailed anatomical description of extrahepatic congenital portosystemic shunts with a balloon occlusion test in order to plan the best surgical approach and avoid unnecessary liver transplantation.

Percutaneous major aortopulmonary collateral artery banding using a covered stent in an infant

We report a 6-month-old infant with pulmonary atresia with ventricular septal defect who was successfully treated with a novel technique of percutaneous major aortopulmonary collateral artery (MAPCA) banding with a covered stent. He suffered from heart failure due to a residual MAPCA of 4.5 mm in diameter. A covered stent tied with 2 5-0 size nylon threads was successfully deployed into the MAPCA in a dumbbell shape with a banding diameter of 2.8 mm. Banding covered stent implantation is a useful method to reduce the pulmonary blood flow in patients with MAPCA, which could be a less-invasive alternative to surgery.

Pre and postnatal diagnosis of congenital portosystemic shunt: Impact of interventional therapy

INTRODUCTION

Congenital portosystemic shunts (CPSS) are rare vascular malformations that can lead to severe complications. With advanced imaging techniques, diagnosis is becoming more feasible occurring in fetal life. Different approaches have been adopted to manage these cases, with an increased utilization of interventional therapy recently. This cohort aims to describe the course of children diagnosed with CPSS and the impact of interventional therapy on the outcome.

METHODS

Retrospective chart review was done for all patients who were diagnosed with CPSS in our institution between January 2006 and December 2015.

RESULTS

Six patients were diagnosed with CPSS. During this period, 8,680 mothers carrying 9548 fetuses underwent fetal ultrasound examinations. Three patients were diagnosed antenatally at a median [IQ] gestational age of 33 [26-33] weeks, and three patients were diagnosed postnatally at 0, 2, and 43 months, respectively. At a median follow-up of 87 [74-110] months, 5 patients are alive; 4 of whom had received transcatheter closure for different indications, and one who had spontaneous resolution of her CPSS. One infant died at the age of 6 weeks secondary to sepsis.

CONCLUSION

CPSS can result in significant complications in children. Interventional therapy is feasible at any age group, but long-term follow-up is warranted.

Congenital Portosystemic Shunts: Current Diagnosis and Management

Congenital portosystemic shunts are increasingly recognized in several settings and at any age. The following are some of the most common presentations: prenatal ultrasound, neonatal cholestasis, incidental finding on abdominal imaging, or systemic complications such as unexplained cardiopulmonary or neurological disease, or the presence of liver nodules in a noncirrhotic liver. The purpose of the present review is to summarize clinical presentation and current recommendations for management, and highlight areas of future research. Illustrative examples from the veterinary literature complement our current lack of knowledge of this rare malformation often masquerading as a multisystem disease.

Abernethy malformation: Our experience from a tertiary cardiac care center and review of literature

Abernethy malformation, also called as congenital extrahepatic portosystemic venous shunt, is a rare anomaly involving the portal venous system. Although rare, it is increasingly being reported and is important to diagnose given the adverse clinical consequences in untreated patients. It has myriad of clinical presentations, from being completely asymptomatic to causing hepatic carcinoma, hepatic encephalopathy, severe pulmonary hypertension, and diffuse pulmonary arteriovenous malformation. We describe our experience with five cases in a tertiary pediatric cardiac care center with Abernethy malformation, with review of literature and also discuss possible therapeutic implications.

Congenital extrahepatic portosystemic shunt: description of four cases and review of the literature

Congenital extrahepatic portosystemic shunt (CEPS), also known as Abernethy malformation, is a rare condition in which the splenomesenteric blood drains directly into a systemic vein, bypassing the liver through a complete or partial shunt. The diagnosis is frequently made during childhood in the setting of neonatal cholestasis, hypergalactosemia, failure to thrive, mental retardation or other congenital defects. In adulthood, CEPS is usually found incidentally during diagnostic work-up for abdominal pain, liver test abnormalities, liver nodules, portopulmonary hypertension, portopulmonary syndrome or portosystemic encephalopathy. The diagnosis depends on imaging and portal venography, but sometimes only liver biopsy can be resolutive, demonstrating the absence of venules within the portal areas. Here we report four recent cases of Abernethy malformation diagnosed in young adults, in which ultrasound (US) was the initial imaging technique and allowed to suspect the diagnosis. Furthermore, we reviewed clinical presentations, associated anomalies and treatment of the 310 cases of CEPS previously reported in the literature.

Outcome of intrahepatic portosystemic shunt diagnosed prenatally

We analyzed the characteristics of the population with congenital portosystemic shunt diagnosed during the antenatal period and the organization of their perinatal care. This multicentric retrospective study included all the patients with a prenatal diagnosis of congenital portosystemic shunt. Between 1999 and 2015, 12 patients were included. Prenatal diagnosis was done at a median 26.5 weeks of gestation (21-34). All the patients presented intrahepatic CPSS, three of them had associated congenital cardiopathy, and one a Bannayan-Zonana syndrome. Ten patients had simple outcome on conservative treatment, eight of them having a spontaneous closure of their portosystemic shunt within the first 2 years of life. One patient had surgical treatment which failed and he developed a focal nodular hyperplasia. Another patient had radiological interventional closure of his shunt which was complicated by a venal portal thrombosis.

CONCLUSION

Outcome of intrahepatic portosystemic shunt diagnosed prenatally is good in the majority of cases. What is known: • Multiples studies exist on congenital porto systemic shunt but when the diagnosis is done after birth. • The evolution, management, and complication are well known. What is new: • There is very few studies with only patients diagnosed in antenatal and it is a large series of cases. • Outcome of intrahepatic portosystemic shunt diagnosed prenatally is good in the majority of cases.

Abernethy malformation: beware in cases of unexplained hepatic encephalopathy in adults-case report and review of the relevant literature

The Abernethy malformation consists of a congenital extrahepatic portosystemic shunt and is believed to be extremely rare in humans. The potential implications of abnormal portovenous shunting and decreased hepatic portal flow are numerous and potentially serious. Although congenital extrahepatic portosystemic shunts are increasingly suspected and diagnosed in specialized centres, much of their clinical presentation and natural history is not fully understood. Symptoms of portosystemic shunt are mainly caused by increased levels of ammonia, which lead to signs of encephalopathy. Therapeutic options depend on the type of shunt and its clinical course, so the classification of the congenital portosystemic shunt is a key finding in these patients.

Congenital Malformations Leading to Paradoxical Embolism

The absolute separation of the right and left circulations and the filtration of blood by the pulmonary circulation are essential to prevent the passage of thrombotic material from the venous system into the systemic arterial circulation. Any breach of the intracardiac septae or circumvention of the pulmonary capillary network may cause a paradoxical embolus. The most common causes are atrial septal defects and pulmonary arteriovenous malformations. This article discusses unusual connections and pathways related to congenital malformations. Although anticoagulation is necessary to prevent paradoxical emboli, the hematologic disturbances and the most appropriate therapy in these patients warrant further investigation.

Single Stage Endovascular Treatment of a Type 2 Abernethy Malformation: Successful Nonsurgical Outcome in a Case Report

Abernethy malformations are a rare collection of congenital hepatic portosystemic shunts. Our 19-year-old patient is with a type 2 Abernethy malformation elected permanent shunt closure following worsening dyspnea. This report details a single stage endovascular technique wherein shunt closure was achieved immediately by placement of an aortic endograft. At 5-month follow-up, the patient reported decreased shortness of breath. Furthermore, ultrasound investigation demonstrated a patent portal vein and right heart catheterization 6 months after procedure revealed decreased pulmonary hypertension relative to preprocedure values. This one step method may serve as an alternative treatment strategy to multistage endovascular closure techniques of type 2 Abernethy malformations.

Congenital portosystemic shunts with and without gastrointestinal bleeding - case series

BACKGROUND

The clinical presentation of congenital portosystemic shunt is variable and gastrointestinal bleeding is an uncommon presentation.

OBJECTIVE

To describe the imaging features of congenital portosystemic shunt as it presented in 11 children with (n = 6) and without gastrointestinal bleeding (n = 5).

MATERIALS AND METHODS

We performed a retrospective study on a clinical and imaging dataset of 11 children diagnosed with congenital portosystemic shunt.

RESULTS

A total of 11 children with congenital portosystemic shunt were included in this study, 7 with extrahepatic portosystemic shunts and 4 with intrahepatic portosystemic shunts. Six patients with gastrointestinal bleeding had an extrahepatic portosystemic shunt, and the imaging results showed that the shunts originated from the splenomesenteric junction (n = 5) or splenic vein (n = 1) and connected to the internal iliac vein. Among the five cases of congenital portosystemic shunt without gastrointestinal bleeding, one case was an extrahepatic portosystemic shunt and the other four were intrahepatic portosystemic shunts.

CONCLUSION

Most congenital portosystemic shunt patients with gastrointestinal bleeding had a shunt that drained portal blood into the iliac vein via an inferior mesenteric vein. This type of shunt was uncommon, but the concomitant rate of gastrointestinal bleeding with this type of shunt was high.

Noncirrhotic Extrahepatic Portosystemic Shunt Causing Adult-Onset Encephalopathy Treated with Endovascular Closure

A 54-year-old woman presented with a six-month history of episodic confusion and progressive ataxia. A comprehensive metabolic panel was notable for elevated values of alkaline phosphatase (161 U/L), total bilirubin (1.5 mg/dL), and serum ammonia of 300 umol/L (normal range 9–47). Hepatitis panel, relevant serological tests, tumor markers (CA-19-9, CEA), and urea cycle enzyme studies were unrevealing. Lactulose and rifaximin therapy failed to normalize serum ammonia levels. Imaging revealed a structural vascular abnormality communicating between an enlarged inferior mesenteric vein and the left renal vein, measuring 16 mm in greatest diameter. The diagnosis of congenital extrahepatic portosystemic shunt was made and endovascular shunt closure was performed using a 22 mm Amplatzer II vascular plug. Within a day, serum ammonia levels normalized. Lactulose and rifaximin were discontinued, and confusion and ataxia resolved.

The classification based on intrahepatic portal system for congenital portosystemic shunts

BACKGROUND/PURPOSE

Liver transplantation was previously indicated as a curative operation for congenital absence of portal vein. Recent advances in radiological interventional techniques can precisely visualize the architecture of the intrahepatic portal system (IHPS). Therefore, the therapeutic approach for congenital portosystemic shunt (CPS) needs to be reevaluated from a viewpoint of radiological appearances. The aim of this study was to propose the IHPS classification which could explain the pathophysiological characteristics and play a complementary role of a therapeutic approach and management for CPS.

METHODS

Nineteen patients with CPS were retrospectively reviewed. The median age at diagnosis was 6.8 years old. Eighteen of these patients underwent angiography with a shunt occlusion test and were classified based of the severity of the hypoplasia of IHPS.

RESULTS

The eighteen cases who could undergo the shunt occlusion test were classified into mild (n=7), moderate (n=6) and severe types (n=5) according to the IHPS classification. The IHPS classification correlated with the portal venous pressure under shunt occlusion, the histopathological findings, postoperative portal venous flow and liver regeneration. Shunt closure resulted in dramatic improvement in the laboratory data and subclinical encephalopathy. Two patients with the severe type suffered from sepsis associated with portal hypertension after treatment, and from the portal flow steal phenomenon because of the development of unexpected collateral vessels. The patients with the severe type had a high risk of postoperative complications after shunt closure in one step, even if the PVP was relatively low during the shunt occlusion test.

CONCLUSION

The IHPS could be visualized by the shunt occlusion test. The IHPS classification reflected the clinicopathological features of CPS, and was useful to determine the therapeutic approach and management for CPS.