From the Guidelines
Thrombophilia Panel for Unprovoked Deep Vein Thrombosis (DVT)
A thrombophilia panel is strongly recommended for patients with unprovoked Deep Vein Thrombosis (DVT) to identify underlying coagulation disorders that may increase the risk of recurrent thrombosis 1.
Components of the Thrombophilia Panel
The panel should include tests for:
- Factor V Leiden
- Prothrombin G20210A mutation
- Antithrombin
- Protein C
- Protein S Additionally, tests for antiphospholipid antibodies, including lupus anticoagulant, anti-cardiolipin, and anti-β2-glycoprotein I antibodies, should be considered 1.
Management of Unprovoked DVT with Confirmed Thrombophilia
Patients with unprovoked DVT and a confirmed thrombophilia should be considered for extended anticoagulation with a vitamin K antagonist, such as warfarin, with a target INR of 2.0-3.0, or a direct oral anticoagulant, such as rivaroxaban 20mg daily, apixaban 5mg twice daily, or dabigatran 150mg twice daily 1. The duration of anticoagulation should be individualized based on the patient's risk of recurrent thrombosis and anticoagulant-related bleeding.
Additional Testing
It is also recommended to test for homocysteine levels and to consider testing for other rare thrombophilic conditions, such as Factor VIII and Factor XI, in selected patients 1.
Key Considerations
- The risk of recurrent VTE is high in patients with unprovoked DVT, with an estimated risk of 10% by 1 year and up to 30% by 5 to 10 years 1.
- The decision to extend anticoagulation should be based on the patient's risk of recurrent thrombosis and anticoagulant-related bleeding 1.
- Regular monitoring and reassessment of the patient's risk-benefit profile is essential to guide management decisions 1.
From the Research
Thrombophilia Panel for Unprovoked Deep Vein Thrombosis (DVT)
The thrombophilia panel for unprovoked DVT includes several factors that can help predict the development of recurrent events. These factors are:
- Thrombophilia 2, 3, 4, 5
- Clinical presentation with primary DVT 2, 4, 5
- Proximal location of DVT 4, 5
- Obesity 4, 5
- Old age 2, 4, 5
- Male sex 4, 5
- Non-0 blood group 5
- Persistence of residual vein thrombosis at ultrasound assessment 4, 5
- Persistently high values of D-dimer 4, 5
- Early development of the post-thrombotic syndrome 5
Role of Thrombophilia
Thrombophilia is a factor that can increase the risk of recurrent VTE in patients with unprovoked DVT 2, 3, 4, 5. However, the role of inherited thrombophilia is controversial 4, 5.
Assessment of Recurrent VTE Risk
The assessment of recurrent VTE risk can be done using clinical prediction guides that stratify patients with unprovoked VTE according to their risk for disease recurrence 3. These guides can help clinicians in decisions about the duration of anticoagulation.
Management of Unprovoked VTE
The management of patients with unprovoked VTE is a common and challenging clinical problem 3. The latest international guidelines suggest indefinite anticoagulation for most patients with the first episode of unprovoked VTE 4, 6, 5. However, new scenarios and opportunities are being offered by the identification of risk stratification models and by strategies that have the potential to help identify patients in whom anticoagulation can be safely discontinued 4, 5.