Clinical and Radiologic Manifestations of Congenital Extrahepatic Portosystemic Shunts: A Comprehensive Review

Abstract

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.

Portal vein variations in 1000 patients: surgical and radiological importance

“…CEPSs are associated with hepatic encephalopathy, nodular liver lesions (focal nodular hyperplasia, regenerative nodular hyperplasia, hepatic adenoma) hepatopulmonary syndrome and concomitant systemic congenital anomalies. 16 Association with biliary variations Embryologically, the intrahepatic bile ducts develop from bipotent liver progenitor cells which are in contact with the mesenchyme of the PV and thus form the "ductal plates". Thus, anatomic variations in intrahepatic branching pattern of PV are usually associated with variant biliary anatomy since embryological development of the hepatic duct occurs later than development of the primary divisions of the PV.…”

Extrahepatic shunt. Unusual cause of hepatic encephalopathy

“…Clinical manifestations are secondary to abnormal development of the liver in which low blood flow can lead to liver ischemia and compensatory increased arterial blood flow may appear as focal nodular hyperplasia or adenoma. Another clinical manifestation due to the presence of shunt is HE especially in older adults, whose brain is more sensitive to hyperammonemia (2). This disease should be suspected in patients with behavioral disturbances and fluctuations in the level of consciousness without evidence of chronic liver disease with elevated blood ammonium.…”

TIPS treatment in a patient with severe lower gastrointestinal bleeding with a misdiagnosis of cirrhotic portal hypertension

“…Ectopic varices, defined by large portosystemic venous collaterals occurring anywhere in the gastrointestinal tract, are less common and account for between 1% and 5% of all variceal bleeding (4,5). Bleeding from ectopic varices, which is rare in patients with portal hypertension, is generally massive and life threatening.…”