What is the treatment for near complete occlusion of the main portal vein at the confluence associated with Superior Mesenteric Vein (SMV) and Splenic vein extrinsic compression?

From the Guidelines

The treatment for near-complete occlusion of the main portal vein at the confluence with associated superior mesenteric vein (SMV) and splenic vein extrinsic compression requires prompt anticoagulation therapy, as recommended by the most recent guidelines 1.

Key Considerations

• The patient's condition involves near-complete occlusion of the main portal vein, which is a significant indication for anticoagulation therapy to prevent further complications such as intestinal ischemia, variceal bleeding, and progressive liver dysfunction.
• The involvement of more than one vascular bed (SMV and splenic vein) and the presence of extrinsic compression suggest a high risk of thrombus progression and potential liver transplantation candidacy, which are factors that increase the benefit of recanalization 1.
• The American Gastroenterological Association (AGA) clinical practice update on management of portal vein thrombosis in patients with cirrhosis recommends anticoagulation for patients with recent (<6 months) portal vein thrombosis that is >50% occlusive or involves the main portal vein or mesenteric vessels 1.

Treatment Approach

• Immediate initiation of low molecular weight heparin (LMWH) such as enoxaparin 1 mg/kg twice daily subcutaneously is recommended, followed by transition to oral anticoagulants like warfarin (target INR 2-3) or direct oral anticoagulants (DOACs) such as rivaroxaban 15-20 mg daily for at least 3-6 months 1.
• Concurrent management should include addressing the underlying cause of extrinsic compression, which may require surgical intervention, endovascular stenting, or treatment of underlying conditions like pancreatitis, malignancy, or inflammatory processes.
• Patients should undergo regular imaging follow-up with Doppler ultrasound every 3 months initially to monitor recanalization.
• Supportive measures include management of portal hypertension complications if present, such as beta-blockers (propranolol 20-40 mg twice daily) for varices prophylaxis and diuretics (spironolactone 100 mg daily with furosemide 40 mg daily) for ascites.

Rationale

• The AGA clinical practice update on management of portal vein thrombosis in patients with cirrhosis provides the most recent and highest-quality guidance on the management of portal vein thrombosis, including the use of anticoagulation therapy for patients with recent portal vein thrombosis that is >50% occlusive or involves the main portal vein or mesenteric vessels 1.
• The use of LMWH and oral anticoagulants is supported by the guidelines, which recommend individualized decision-making based on patient preference and Child-Turcotte-Pugh class 1.
• The management of portal hypertension complications and the use of supportive measures such as beta-blockers and diuretics are also recommended by the guidelines 1.

From the Research

Near Complete Occlusion of Main Portal Vein at Confluence

• The main portal vein occlusion at confluence associated with SMV and splenic vein extrinsic compression is a complex condition that requires careful management.
• According to 2, anticoagulant therapy is recommended for patients with acute symptomatic portal vein thrombosis to obtain greater vessel recanalization and reduce the occurrence of portal-hypertension related complications.

Treatment Options

• Different treatment options can be considered, including unfractionated or low molecular weight heparin, vitamin K antagonists, and direct oral anticoagulants (DOACs) 2.
• In cases where the occlusion is caused by tumor invasion, segmental resection of the SMPV confluence at the time of pancreaticoduodenectomy may be necessary 3.

Risk Factors and Prevention

• Patients undergoing splenectomy have an increased risk of splenic/portal vein thrombosis, with risk factors including big spleens and hereditary hemolytic anemias 4.
• Postoperative antithrombotic prophylaxis may be necessary to prevent splenic vein thrombosis, although well-designed randomized studies on this topic are urgently needed 4.

Management of Portal Vein Thrombosis

• The management of portal vein thrombosis depends on the underlying cause and may involve anticoagulant therapy, thrombectomy, or other interventions 5, 6.
• The presence of PVT should be considered as a clue for prothrombotic disorders, liver disease, and other local and general factors that must be carefully investigated 6.