Hepatic Blood Flow Obstruction

Introduction

• Due to dual blood supply the liver does not typically infarct
• Flow can be obstructed in 3 places
  • pre-hepatic
    • caused mainly by vessel thrombosis
      • transplant rejection (hepatic artery) 
      • polyarteritis nodosa (hepatic artery) 
      • pyelphlebitis (portal vein)
      • hepatocellular carcinoma (portal vein)
  • intra-hepatic
    • causes
      • cirrhosis
      • Budd-Chiari syndrome/centrilobular hemorrhagic necrosis 
        • ischemic sequelae of heart failure
        • centrilobular region perfused last and is the first to infarct
  • post-hepatic
    • caused by thrombosis of hepatic vein due to
      • malignancy invasion (e.g. hepatocellular carcinoma)
      • polycythemia vera 
      • hypercoagulable states (e.g. pregnancy)
    • Budd-Chiari syndrome 
      • occlusion of hepatic veins that causes blood to back up into the liver 
        • can lead to centrilobular congestion and necrosis
          • congestive liver disease can ensue with symptoms of:
            • hepatomegaly
            • ascites
            • varices
            • abdominal pain
            • liver failure
          • potential causes
            • polycythemia vera
            • CHF
            • hepatocellular carcinoma
            • postpartum state
            • hypercoaguable state
            • anything that causes hepatic vein thrombosis
          • pathological findings
            • classicaly described as a “nutmeg liver”
          • treatment
            • sodium restriction
            • anticoagulation:
              • heparin
              • warfarin
            • surgical shunts
            • liver transplanation in patient with fluminant liver failure
• recurrence of disease is common

Presentation

• Physical exam
  • pre-hepatic
    • portal hypertension
    • ascites
    • NO hepatomegaly
  • intra-hepatic
    • hepatomegaly
    • portal hypertension
    • ascites
  • post-hepatic
    • hepatomegaly
    • portal hypertension
• ascites

Evaluation

• Intra-hepatic
  • liver biopsy
    • “nutmeg” appearance
      • secondary to blood congestion/necrosis around central veins
  • labs
    • ↑ transaminases
• Post-hepatic
  • ultrasound is test of choice
  • labs
    • ↑ transaminases