What is the recommended treatment for portal vein thrombosis?

Treatment of Portal Vein Thrombosis

Anticoagulation is the cornerstone of treatment for portal vein thrombosis, with specific indications and agent selection based on the clinical presentation, degree of occlusion, and severity of underlying liver disease. 1

Indications for Anticoagulation

Definite Indications (Strong Recommendations)

• Symptomatic PVT: All patients with symptomatic portal vein thrombosis require therapeutic anticoagulation for a minimum of 6 months to prevent thrombus extension and bowel ischemia. 1

• Acute complete or partial main portal vein occlusion: Recent thrombosis (less than 6 months) that is completely or partially occlusive (>50%) of the main portal vein trunk requires anticoagulation. 1

• Progressive thrombosis: Asymptomatic but progressing PVT warrants anticoagulation for a minimum of 6 months unless clear contraindications exist. 1

• Liver transplant candidates: Extended anticoagulation should be continued for all patients with cirrhosis and PVT who are candidates for liver transplantation unless they are actively bleeding. 1

Conditional Indications

• Minimally occlusive thrombosis (<50%): If the thrombus progresses on short-term follow-up (1-3 months) or compromises the superior mesenteric vein, anticoagulation is indicated. 1

• Asymptomatic PVT in non-transplant candidates: May be considered on a case-by-case basis as anticoagulation may be associated with a survival benefit, with regular reassessment of bleeding risk at 6-monthly intervals. 1

Contraindications

• Chronic complete occlusion with cavernous transformation: AASLD recommends against anticoagulation in chronic complete occlusion of the main portal vein or cavernous transformation with established collaterals. 1

• Active bleeding: Anticoagulation should be withheld during active bleeding episodes. 1

Choice of Anticoagulant Agent

Child-Pugh A or B Cirrhosis

Either DOAC or LMWH with/without VKA are acceptable options for patients with Child-Pugh A or B cirrhosis. 1

• LMWH, vitamin K antagonists, and direct oral anticoagulants are all endorsed by recent guidelines (AASLD and Baveno Faculty). 1
• Initial therapy preferably with LMWH according to Baveno VII. 1
• Maintenance therapy can utilize LMWH, VKA, or DOAC. 1

Child-Pugh C Cirrhosis

LMWH alone is the preferred agent for patients with Child-Pugh C cirrhosis, or as a bridge to VKA in patients with a normal baseline INR. 1

• DOACs are contraindicated in Child-Pugh C cirrhosis due to risk of accumulation. 2
• LMWH is safer than unfractionated heparin in cirrhotic patients (bleeding rate 0% vs 19.2%). 2

Non-Cirrhotic Patients

• Initial therapy with unfractionated heparin or LMWH. 1
• Maintenance with LMWH, VKA, or DOAC are all reasonable options. 1, 3

Duration of Treatment

• Minimum 6 months for all patients with symptomatic or progressive PVT. 1, 3, 4

• Until transplantation for liver transplant candidates. 1, 3

• Lifelong anticoagulation should be considered for patients with superior mesenteric vein involvement, history of intestinal ischemia, or underlying permanent pro-coagulant conditions. 3, 4

• After recanalization: Consider prolonging anticoagulation as recurrence rates up to 38% have been reported when anticoagulation is stopped. 3

Critical Pre-Treatment Assessment

Evaluate for the presence of varices and ensure adequate management prior to initiating anticoagulant therapy. 1

• Screen for esophageal varices before starting anticoagulation. 3
• Use beta-blockers or band ligation to prevent variceal bleeding in patients with varices. 3
• Implement adequate prophylaxis for gastrointestinal bleeding before starting anticoagulation in cirrhotic patients. 3

Monitoring and Follow-Up

• Imaging every 3 months to assess treatment response. 3
• Recanalization can be expected to occur up to 6 months after starting treatment. 3
• Time interval less than 6 months between diagnosis and anticoagulation initiation is the most important predictor of successful recanalization. 3
• Regular reassessment of bleeding risk at 6-monthly intervals if anticoagulation is continued. 1

Advanced Interventions

Consider transjugular intrahepatic portosystemic shunt (TIPS) for liver transplant candidates with progressive PVT not responding to anticoagulation, or for patients with additional indications such as refractory ascites or variceal bleeding. 1, 3

• Local thrombolysis should be avoided due to high risk of major bleeding complications. 3
• Surgical thrombectomy has limited success and high recurrence rates. 3

Important Safety Considerations

• Overall bleeding complications with anticoagulation occur in approximately 5-14% of patients. 3
• Risk factors for bleeding include history of variceal bleeding, low serum albumin, and platelet count less than 50×10⁹/L. 3
• Over half of patients not achieving recanalization will develop gastroesophageal varices during follow-up. 3
• Severe portal biliopathy can develop in 30% of patients with acute PVT within 1 year. 3

Common Pitfalls to Avoid

• Do not withhold anticoagulation in cirrhotic patients based solely on elevated INR or thrombocytopenia, as these do not reliably predict bleeding risk. 1
• Do not delay anticoagulation beyond 6 months from diagnosis, as this significantly reduces recanalization success. 3
• Do not use DOACs in Child-Pugh C cirrhosis or in patients with creatinine clearance <30 mL/min without extreme caution. 2
• Do not forget to screen and manage varices before initiating anticoagulation. 1, 3