Spontaneous Intrahepatic Portosystemic Venous Shunt

Abstract

Purpose: Intrahepatic portosystemic venous shunts are rare and not well recognized. We report the case of a patient with a spontaneous intrahepatic portosystemic venous shunt. Methods: A 48 year old Hispanic woman was referred for a 1.6 cm enhancing lesion of unclear etiology in the right lobe of the liver identified on a CT scan that was performed by her primary care physician for evaluation of her abdominal pain. At her initial office visit she reported mild abdominal discomfort. Physical exam was revealed tenderness in her right upper quadrant. Laboratory evaluation was unremarkable, including normal LFTs, a normal Alpha-fetoprotein, and negative viral hepatitis serologies. MRI of the liver was performed and demonstrated a vascular malformation in the right lobe of the liver being fed by a branch of the portal vein and drained by a tributary of the hepatic vein. This lesion is compatible with a rare spontaneous intrahepatic portosystemic venous shunt. Results: Spontaneous intrahepatic portosystemic venous shunts are rare, described mostly in small series or case reports. More commonly these shunts are acquired in the setting of trauma or developed in chronic liver disease, and are generally due to an abnormal communication between the portal circulation and an extrahepatic systemic vein. The clinical significance and treatment of these shunts remains controversial. Instances of intrahepatic portosystemic venous shunts causing encephalopathy and larger fistulas adversely effecting systemic hemodynamics as well as causing liver fibrosis from longstanding diversion of portal flow have been reported. Treatment options include conservative management, surgery, or transcatheter embolization in symptomatic patients. IPSVS found in asymptomatic patients without liver disease are not thought to require treatment. Conclusion: We report a case of an asymptomatic spontaneous intrahepatic portosystemic venous shunt. The long term sequelae of this anatomic abnormality are not well described.Figure: T1-weighted MRI of the liver demonstrating a vascular malformation in the inferior aspect of the right lobe of the liver being fed by a branch of the portal vein and drained by a tributary of the hepatic vein.