What is the management of subclavian deep vein thrombosis (DVT) in patients with a Port-a-Cath (implantable venous access device)?

From the Guidelines

Management of subclavian deep vein thrombosis (DVT) in patients with a port catheter typically involves anticoagulation therapy while maintaining the catheter in place if it's still functional and needed. The recommended approach is to start with therapeutic anticoagulation using low molecular weight heparin (LMWH) such as enoxaparin 1 mg/kg twice daily or 1.5 mg/kg once daily, or direct oral anticoagulants (DOACs) like rivaroxaban 15 mg twice daily for 21 days followed by 20 mg daily, or apixaban 10 mg twice daily for 7 days followed by 5 mg twice daily, as suggested by the NCCN guidelines 1.

Key Considerations

• Treatment should continue for at least 3 months or for as long as the catheter remains in place.
• The port catheter can be retained if it's still functioning properly, has no infection, is still needed for treatment, and is correctly positioned.
• Catheter removal should be considered if there's infection, malfunction, or if the catheter is no longer needed.
• If removal is necessary, provide anticoagulation for at least 3-5 days before removal and continue for at least 4-6 weeks afterward to prevent clot embolization.
• Regular monitoring for symptoms of pulmonary embolism, catheter dysfunction, or infection is essential.

Rationale

This approach balances the need to treat the thrombosis while preserving venous access that may be crucial for ongoing patient care, as catheter-related thrombosis often responds well to anticoagulation without necessitating immediate catheter removal, as indicated by the guidelines 1.

Additional Recommendations

• Consider catheter-directed therapy (pharmacomechanical thrombolysis or mechanical thrombectomy) in appropriate candidates, as suggested by the NCCN guidelines 1.
• Follow patients with contraindication to anticoagulation until the contraindication resolves or DVT progression occurs, at which point re-evaluation of the risk/benefit of anticoagulation is recommended 1.

From the Research

Management of Subclavian DVT in Patients with Port Catheter

• The management of subclavian deep vein thrombosis (DVT) in patients with a port catheter is crucial to prevent complications such as pulmonary embolism and post-thrombotic syndrome.
• According to the study by 2, the treatment of DVT includes anticoagulation options such as unfractionated heparin, low molecular weight heparin, fondaparinux, and direct oral anticoagulants (DOACs).
• Low molecular weight heparin (LMWH) has been shown to be effective and safe in the treatment of DVT, as demonstrated in studies by 3 and 4.
• The study by 4 compared fixed-dose subcutaneous enoxaparin with adjusted-dose intravenous unfractionated heparin in the treatment of proximal DVT and found that enoxaparin was at least as effective and safe as unfractionated heparin.
• In patients with subclavian/axillary DVT, the possibility of thoracic outlet syndrome should be considered, as mentioned in the study by 2.
• The optimal duration of anticoagulation therapy is dictated by the presence of modifiable thrombotic risk factors, and long-term anticoagulation should be considered in patients with unprovoked DVT or persistent prothrombotic risk factors such as cancer, as stated in the study by 2.

Anticoagulation Options

• Unfractionated heparin: can be used as an initial treatment for DVT, but requires close monitoring of activated partial thromboplastin time (aPTT) levels, as mentioned in the study by 3.
• Low molecular weight heparin (LMWH): has been shown to be effective and safe in the treatment of DVT, and can be administered subcutaneously, as demonstrated in studies by 3 and 4.
• Direct oral anticoagulants (DOACs): are as effective as conventional therapy with LMWH and vitamin K antagonists, but may have a higher risk of bleeding, as mentioned in the study by 2.

Special Considerations

• Patients with a port catheter may require special consideration when initiating anticoagulation therapy, as the catheter can increase the risk of thrombosis, as mentioned in the study by 2.
• The study by 5 demonstrated that therapeutic-dose LMWH can reduce major thromboembolism and death in high-risk hospitalized patients with COVID-19, but the results may not be generalizable to patients with subclavian DVT and a port catheter.