Intrahepatic Portosystemic Venous Shunt in a Non-Cirrhotic Adult Female with Encephalopathy

Abstract

Introduction: Intrahepatic portosystemic venous shunts (IPSVS) are rare anomalous vascular connections within the liver that are often asymptomatic. However, significant shunting of blood may present as encephalopathy. Cross sectional imaging and Doppler studies are essential to characterize the shunt and determine portosystemic shunt ratios. High flow shunts may be treated using coil embolization or surgery. Result: We present the case of a 57-year-old previously asymptomatic lady who was admitted for confusion and behavioral change. Work-up revealed deranged liver function and hyperammonemia. Triphasic CT scan showed an aneurysmal connection between the right anterior portal vein and the middle hepatic vein measuring 1.9 cm in widest diameter. The left portal vein was small. The liver had homogenous parenchyma and smooth borders. Aside from small hepatic cysts, there were no other lesions detected. Doppler ultrasound showed turbulent flow across the connection with a portovenous shunt ratio of 73%. The size of the shunt precluded safe coil embolization. Surgical treatment was then opted for and she underwent a hepatotomy from the superior border of the liver until the aneurysmal shunt connection was identified and isolated. The connection was then divided between clamps and the stumps sutured close. Blood flow in the left portal vein then increased immediately. Her postoperative course was unremarkable and she was discharged improved. She remains well 8 months after surgical correction of the shunt. Conclusion: A high index of suspicion should prompt the search for IPSVS in patients presenting with encephalopathy in the absence of liver cirrhosis. Imaging studies are essential in assessing the type and severity of the portovenous shunting and in guiding the management. Symptomatic patients with high shunt ratios should be treated promptly using interventional radiologic procedures or surgery.