2332 Large Hepatic Arteriovenous Fistula Leading to Non-Cirrhotic Portal Hypertension and Associated Complications

Abstract

INTRODUCTION: Portal hypertension (and its complications including bleeding, ascites, encephalopathy) often occur in patients with liver cirrhosis as a result of intrahepatic resistance to portal blood flow and increased portal collateral blood flow. Non-cirrhotic portal hypertension (NCPH) is less common, but can also lead to similar complications. Arteriovenous fistulas are an uncommon presinusoidal intrahepatic cause of NCPH. We present a rare case of a patient with a remote history of a liver biopsy who presented with new onset ascites and found on imaging to have a large hepatic arteriovenous fistula which was subsequently treated with embolization. CASE DESCRIPTION/METHODS: A 61 year old male with no significant past medical history presented to clinic for evaluation of progressively worsening abdominal and lower extremity swelling. Laboratory findings on presentation were remarkable for hemoglobin 7.4 g/dL, platelets 59,000/microliter, INR 1.6, Na 137mmol/L, Cr 1.56 mg/dL T bilirubin 2.4 mg/dL. Paracentesis fluid studies showed high serum-ascites albumin gradient (SAAG) and high protein without evidence of heart failure on echocardiogram. Magnetic resonance imaging of the abdomen showed a 6.3 × 4 centimeters hepatic arteriovenous fistula within segment VIII of the liver; the portal vein was noted to be patent. Liver biopsy showed focal perivenular and subsinusoidal fibrosis without bridging (fibrosis stage 1/6) and nodular regenerative hyperplasia changes with bands of hepatocyte atrophy without any evidence of cirrhosis. Right hepatic arteriogram demonstrated a dilated and tortuous vessel with early filling of the portal venous system and a large aneurysm at the communication point between the arterial and venous fistula. Successful embolization of the anterior segmental branch of the right hepatic artery was achieved. The patient’s hospital course was also complicated by upper gastrointestinal bleeding secondary to esophageal varices which required banding x5. DISCUSSION: The presence of portal hypertensive changes with minimal hepatic fibrosis on liver biopsy is best categorized as non-cirrhotic portal hypertension (NCPH). This patient manifested complications of portal hypertension including variceal bleeding and recurrent ascites secondary to a large hepatic arteriovenous fistula which likely formed following his liver biopsy. Closure of large arteriovenous fistulas can be beneficial in preventing worsening portal hypertension and associated potentially fatal complications.