Congenital intrahepatic portosystemic shunt

Endovascular treatment of a portosystemic shunt presenting with hypoglycemia; case presentation and review of literature

Here we present a rare case of hyperinsulinemic-hypoglycemia due to congenital intrahepatic and extrahepatic portosystemic shunts. Performing percutaneous closure of such shunts has been reported to improve symptomatic hypoglycemia in this setting. This case is unique given the type of shunt (both with intrahepatic and extrahepatic components) and the clinical improvement following placement of a single vascular plug to occlude both intrahepatic and extrahepatic connections.

Ultrasound with Doppler evaluation of congenital hepatic vascular shunts

Congenital aberrant hepatic vascular communications result from intrahepatic or extrahepatic errors in vascular development or involution during the transition from fetal to newborn hepatic circulation. These hepatic vascular shunts can be fortuitously discovered and asymptomatic, or can cause symptoms of varying severity, often presenting diagnostic dilemmas. Some hepatic vascular shunts resolve spontaneously while others require interventional radiologic or surgical closure. Affected patients are often first studied with real-time and Doppler ultrasound, so radiologists should familiarize themselves with the expected ultrasound findings of these vascular shunts for effective diagnosis, triage and management. In this review, the authors focus on ultrasound and Doppler findings of hepatic vascular shunts with underlying embryology, clinical features and management strategies. Broadly, these aberrant hepatic vascular communications include portosystemic venous shunts (which can be intra- or extrahepatic and include persistent patent ductus venosus), arterioportal, arteriovenous or mixed shunts.

Congenital portosystemic venous shunt

Congenital portosystemic venous shunts are rare developmental anomalies resulting in diversion of portal flow to the systemic circulation and have been divided into extra- and intrahepatic shunts. They occur during liver and systemic venous vascular embryogenesis and are associated with other congenital abnormalities. They carry a higher risk of benign and malignant liver tumors and, if left untreated, can result in significant medical complications including systemic encephalopathy and pulmonary hypertension.

CONCLUSION

This article reviews the various types of congenital portosystemic shunts and their anatomy, pathogenesis, symptomatology, and timing and options of treatment. What is Known: • The natural history and basic management of this rare congenital anomaly are presented. What is New: • This paper is a comprehensive review; highlights important topics in pathogenesis, clinical symptomatology, and treatment options; and proposes an algorithm in the management of congenital portosystemic shunt disease in order to provide a clear idea to a pediatrician. An effort has been made to emphasize the indications for treatment in the children population and link to the adult group by discussing the consequences of lack of treatment or delayed diagnosis.

Liver resection for the treatment of a congenital intrahepatic portosystemic venous shunt

Intrahepatic portosystemic shunts (IPSS) are rare congenital anomalies arising from disordered portal vein embryogenesis. It has been described in both children and adults and may be asymptomatic or be associated with a variety of neurophysiological and pulmonary complications. When recognized, early intervention to occlude the shunt will reverse the associated complications. Literature review reports of surgical and radiological occlusion of the shunt, but due to its rarity, a standard therapeutic protocol has not been established. A case of a 38-year-old woman with abdominal pain and low grade encephalopathy, diagnosed with an IPSS and treated by right hepatectomy was reported.

Clinical and radiologic manifestations of congenital extrahepatic portosystemic shunts: a comprehensive review

Congenital extrahepatic portosystemic shunt (CEPS) is a rare condition in which the portomesenteric blood drains into a systemic vein, bypassing the liver through a complete or partial shunt. Most often, the diagnosis is made primarily with Doppler ultrasonography. Computed tomographic angiography and magnetic resonance angiography are used for further classification of the shunt and assessment of accompanying anomalies. Conventional angiography is necessary when results of the other tests disagree or are inconclusive. CEPS is classified into two types according to the pattern of anastomoses between the portal vein and systemic vein. In type 1, intrahepatic portal venous supply is absent; in type 2, intrahepatic portal venous supply is preserved. Type 1 usually occurs in girls with associated malformations, such as situs ambiguous with polysplenia and congenital heart defects. Associated anomalies are less frequent in type 2, and symptoms usually develop later without a gender preference. Hepatic encephalopathy and liver dysfunction are possible complications of both types and usually develop during adulthood. Both types are also associated with regenerative hepatic nodules. The clinical setting and imaging appearance of these nodules can help one avoid misdiagnosis. Definitive treatment of CEPS is determined by the type of shunt. Liver transplantation is the only effective treatment for symptomatic type 1 CEPS; surgical closure or embolization of the shunt is the therapeutic approach for type 2.

Radiological and histopathological manifestations of hepatocellular nodular lesions concomitant with various congenital and acquired hepatic hemodynamic abnormalities

Congenital and acquired hepatic hemodynamic abnormalities are classified into four categories: hepatic arterial inflow disorder, portal vein inflow disorder, hepatic vein outflow disorder, and presence of a third inflow to the liver. Although their detailed etiology is not fully understood, these hepatic hemodynamic abnormalities may cause the formation of hepatocellular nodules. Recent advances in imaging modalities now enable visualization of these hepatocellular nodules concomitantly with the identification of various congenital and acquired hemodynamic abnormalities. Most of these nodular lesions are benign hyperplastic nodules, such as focal nodular hyperplasia, nodular regenerative hyperplasia, and other types of regenerative nodules. However, neoplastic nodules such as hepatic adenoma and hepatocellular carcinoma may also occur in conjunction with hepatic hemodynamic abnormalities. Distinguishing neoplastic nodules, especially malignant liver tumors, from hyperplastic nodules is important. Detection of intranodular Kupffer cells with superparamagnetic iron oxide enhanced magnetic resonance imaging is a key indicator that a nodule is regenerative rather than neoplastic.

Congenital Hepatic Shunts

Abnormal vascular connections within the hepatic parenchyma are occasionally seen at ultrasonography (US) and require further evaluation. The radiologic findings in 42 children with infantile hepatic hemangioma (n = 28), vascular malformations (n = 10), or infradiaphragmatic total anomalous pulmonary venous return (TAPVR) (n = 4) associated with congenital vascular shunting were retrospectively reviewed. Arteriovenous connections are seen in infantile hepatic hemangiomas and arteriovenous malformations and manifest with aortic tapering at the level of the celiac trunk, hepatic artery enlargement with a low resistivity index (RI), and increased flow velocities in the hepatic veins that may assume an arterialized spectral pattern in late-stage disease. Congenital arterioportal shunts demonstrate a low RI in the hepatic artery, hepatofugal arterialized flow in the portal vein, and rapid development of signs of portal hypertension. Portosystemic shunting may be intra- or extrahepatic. A pulsatile triphasic spectral pattern is seen in the portomesenteric venous system in children with portosystemic shunting, and macroscopic connections between the portal system and the hepatic veins are evident. Infradiaphragmatic TAPVR is associated with a tortuous vessel that parallels the aorta, ends at the intrahepatic left portal vein or the ductus venosus, and has hepatopetal flow. Familiarity with the US features of various congenital abnormal hepatic vascular connections will aid in diagnosis and treatment.

Symptomatic intrahepatic portosystemic venous shunt: embolization with an alternative approach

OBJECTIVE

Intrahepatic portosystemic venous shunt is relatively rare and not well recognized. Awareness of intrahepatic communications is important because they can cause encephalopathy, and most of these shunts can be completely cured by transcatheter embolization. In this study, we describe the angiographic findings and transcatheter embolization techniques using several approaches for the treatment of intrahepatic portosystemic venous shunt.

MATERIALS AND METHODS

Between 1989 and 2001, we treated 10 patients with symptomatic intrahepatic portosystemic venous shunt by performing transcatheter embolization with Gianturco coils, fibered platinum coils, detachable balloons, and detachable microcoils using one of three approaches to access the portal venous system: transileocolic obliteration (n = 2), percutaneous transhepatic obliteration (n = 4), or retrograde transcaval obliteration (n = 4).

RESULTS

In all patients, complete obliteration or nearly complete obliteration was confirmed angiographically, and symptoms related to portal-systemic encephalopathy improved after treatment. Complications were observed in three patients: adhesive ileus in a patient treated by transileocolic obliteration and thrombosis of intrahepatic portal branches in two patients treated by percutaneous transhepatic obliteration.

CONCLUSION

On angiography, two types of intrahepatic portosystemic venous shunt were seen: intrahepatic portal venous-hepatic venous communication and intrahepatic portal venous-perihepatic venous communication. Transcatheter embolization is effective for treatment of intrahepatic portosystemic venous shunt. Retrograde transcaval obliteration is the least invasive technique and is recommended as the first choice for treatment of portosystemic venous shunt except in patients with multiple shunts.

Intrahepatic portal-hepatic venous anastomosis: a portal-systemic shunt with neurological repercussions

Intrahepatic shunts are rarely diagnosed as a cause of neurocognitive abnormality. A complaint of fatigue led to the diagnosis of a right portal vein-hepatic vein aneurysmal communication in a 23-yr-old, otherwise healthy woman. Neuropsychological testing, imaging, and MR spectroscopy revealed changes similar to those described in patients with cirrhosis and subclinical hepatic encephalopathy. T1-weighted MRI showed a hyperintense globus pallidus, a feature seen in subjects with and without portal-encephalopathy. Portal-systemic shunting in the absence of parenchymal liver disease reproduces neurological features described in cirrhosis.