What is the management approach for anticoagulation after portal vein thrombectomy in patients undergoing liver transplantation?

From the Guidelines

Anticoagulation after portal vein thrombectomy in patients undergoing liver transplantation should be managed with immediate postoperative heparin followed by transition to oral anticoagulants, with a preference for direct oral anticoagulants like rivaroxaban or apixaban in select patients with good liver function, as evidenced by recent studies 1. The management approach for anticoagulation after portal vein thrombectomy in patients undergoing liver transplantation involves several key considerations, including the risk of rethrombosis, bleeding risks, and the patient's underlying liver function.

• Unfractionated heparin is usually started within 24-48 hours post-transplant once hemostasis is achieved, with an initial target aPTT of 40-60 seconds.
• Low molecular weight heparin (such as enoxaparin 40-60 mg twice daily) may be substituted once liver function stabilizes.
• Patients are then transitioned to warfarin with a target INR of 2-3, generally maintained for 3-6 months.
• Direct oral anticoagulants like rivaroxaban or apixaban are preferred in select patients with good liver function, due to their ease of use and convenience, as noted in recent studies 1.
• Antiplatelet therapy with aspirin 81-100 mg daily is often added to the regimen. Regular monitoring of coagulation parameters, liver function, and imaging studies (Doppler ultrasound) is essential to assess portal vein patency and adjust anticoagulation accordingly.
• The anticoagulation approach aims to prevent rethrombosis while balancing bleeding risks, particularly important given the tenuous hemostatic balance in post-transplant patients with evolving liver function.
• Anticoagulation duration may be extended in patients with underlying hypercoagulable states or those with complete portal vein thrombosis prior to transplantation, as suggested by recent guidelines 1.

From the Research

Management Approach for Anticoagulation after Portal Vein Thrombectomy in Patients Undergoing Liver Transplantation

• The management of portal vein thrombosis (PVT) after liver transplantation is a complex issue with no consensus on the ideal treatment 2.
• Anticoagulation and antiplatelet therapies are increasingly used in liver transplant candidates and recipients due to cardiovascular comorbidities, portal vein thrombosis, or to manage posttransplant complications 3.
• Systemic anticoagulation alone can have a positive effect for early PVT patients, while interventional therapy combined with systemic anticoagulation is a good choice for the management of PVT after liver transplantation 2.

Surgical Management of Portal Vein Thrombosis

• A stepwise broad-minded strategy should always be adopted when approaching advanced portal vein thrombosis during liver transplantation 4.
• Thrombectomy was successful in 46 patients (84%) with portal vein thrombosis, and 43 patients had patent portal inflow (93.5%) 5.
• Surgical procedures such as interposition vein grafts, jump grafts from the superior mesenteric vein, and renoportal anastomosis may be necessary to restore portal flow 4.

Anticoagulation Therapy

• The role of anticoagulant treatment in patients with portal vein thrombosis undergoing liver transplantation is still debated 6.
• Systemic anticoagulation (low molecular weight heparin and warfarin) therapy was administered to four patients with PVT after liver transplantation, with positive effects in early PVT patients 2.
• Minimally invasive interventional therapies combined with systemic anticoagulation (heparin and warfarin) were applied for three patients with PVT after liver transplantation 2.