What is the appropriate treatment for extrahepatic portal vein obstruction (EHPVO) and is a proximal splenorenal shunt or Transjugular Intrahepatic Portosystemic Shunt (TIPS) indicated?

Management of Extrahepatic Portal Vein Obstruction (EHPVO)

For patients with extrahepatic portal vein obstruction (EHPVO), surgical portosystemic shunts, particularly proximal splenorenal shunts, are the most effective definitive treatment when endoscopic therapy fails to control variceal bleeding, while TIPS is generally not indicated for EHPVO due to the absence of intrahepatic portal hypertension.

Initial Diagnosis and Management

• First-line investigation: Doppler ultrasound for initial diagnosis 1
• Confirmatory imaging: CT scan with vascular contrast to assess:
  • Absence of visible portal vein lumen
  • Presence of cavernoma (serpiginous vascular channels in porta hepatis)
  • Extension of thrombosis 1

Treatment Algorithm

First-Line Management

1. Anticoagulation therapy:

   • Immediate LMWH in absence of contraindications
   • Transition to oral vitamin K antagonists (target INR 2-3)
   • Continue for at least 6 months 1

2. Variceal management:

   • Screen all patients for gastroesophageal varices
   • Non-selective beta-blockers (propranolol) as first-line prophylaxis
   • Endoscopic band ligation for primary prophylaxis of variceal bleeding 1

Second-Line Management (When Endoscopic Therapy Fails)

Surgical Portosystemic Shunts:

• Proximal splenorenal shunt (PSRS) is the preferred surgical option for EHPVO with:

  • Low mortality rate (0.7% for elective procedures)
  • Good long-term results (15-year survival rate of 95%)
  • Effective control of variceal bleeding
  • Improvement in hypersplenism 2

• Alternative shunts when PSRS is not feasible:

  • Splenoadrenal shunt (SAS)
  • Interposition mesocaval shunt (iMCS)
  • Interposition PSRS (iPSRS)
  • Jejunal vein-cava shunt (JCS) 3

TIPS in EHPVO

TIPS is generally not indicated for EHPVO because:

1. The portal vein is obstructed extrahepatic, making transjugular access to the portal system technically challenging or impossible
2. TIPS creates an intrahepatic shunt, which doesn't address extrahepatic obstruction
3. Surgical shunts have shown better long-term patency rates and fewer reinterventions compared to TIPS in this specific condition 4

Special Considerations

Indications for Surgical Intervention Beyond Variceal Bleeding

• Massive splenomegaly with severe hypersplenism
• Growth retardation
• Isolated gastric and ectopic varices not amenable to endotherapy
• Portal cavernoma cholangiopathy 5

Surgical Outcomes

• Shunt patency: 89% long-term patency rate for proximal splenorenal shunts
• Resolution of hypersplenism in most patients
• Significant improvement in growth parameters in children
• Low risk of encephalopathy in non-cirrhotic EHPVO patients 5, 3

Important Distinctions

• Proximal splenorenal shunt: An end-to-side anastomosis between the splenic vein and renal vein after splenectomy (not a side-to-side shunt)
• Distal splenorenal shunt (Warren): A selective shunt that preserves portal flow, more commonly used in cirrhotic patients 6, 7

Follow-up and Surveillance

• Assess recanalisation with CT scan at 6-12 months
• Regular endoscopic monitoring for varices
• Imaging to assess shunt patency
• Monitoring for development of portal biliopathy 1

Remember that surgical shunts for EHPVO provide freedom from recurrent bleeding and repeated endoscopies for many years, and improve hypersplenism without deteriorating liver function or causing encephalopathy 7.