Anticoagulation for deep venous thrombosis (DVT)

Anticoagulation is the main treatment approach in venous thromboembolism treatment.

• patients with proximal DVT/PE should be anticoagulated for at least 3 months
  
• patients with isolated distal DVT
  • at high-risk of recurrence – anticoagulated as for proximal DVT
  • at low-risk of recurrence - shorter treatment (4–6 weeks), even at lower anticoagulant doses, or ultrasound surveillance may be considered (1,2)

Current guidelines recommend a two phase anticoagulation treatment:

• initial phase of intensified anticoagulation followed by anticoagulation therapy for 3 months
• extended phase of anticoagulation
  • beyond first 3-6 months
  • should consider between the risk for VTE recurrence without long term anticoagulants vs bleeding with anticoagulants (3)

NICE suggest (4):

Anticoagulation treatment for proximal DVT or PE

• measure baseline full blood count, renal and hepatic function, PT and APTT but start anticoagulation before results available. Review and if necessary act on results within 24 hours
• offer anticoagulation for at least 3 months. Take into account contraindications, comorbidities and the person’s preferences
• after 3 months (3 to 6 months for active cancer) assess and discuss the benefits and risks of continuing, stopping or changing the anticoagulant with the person. See long-term anticoagulation for secondary prevention(linked item)

Anticoagulant considerations considered in terms of:

• No renal impairment, active cancer, antiphospholipid syndrome or haemodynamic instability
  • offer apixaban or rivaroxaban
  • if neither suitable, offer one of:
    • LMWH for at least 5 days followed by dabigatran or edoxaban
    • LMWH and a VKA for at least 5 days, or until INR at least 2.0 on 2 consecutive readings, then a VKA alone
      
      
• Renal impairment (CrCl estimated using the Cockcroft and Gault formula; see the BNF)
  
  • CrCl 15 to 50 ml/min, offer one of:
    • apixaban
    • rivaroxaban
    • LMWH for at least 5 days then
      • edoxaban or
      • dabigatran if CrCl >= 30 ml/min
    • LMWH or UFH and a VKA for at least 5 days, or until INR at least 2.0 on 2 consecutive readings, then a VKA alone
      
      
  • CrCl < 15 ml/min, offer one of:
    • LMWH
    • UFH
    • LMWH or UFH and a VKA for at least 5 days, or until INR at least 2.0 on 2 consecutive readings, then a VKA alone
  • Note cautions and requirements for dose adjustments and monitoring in SPCs. Follow local protocols, or specialist or MDT advice
• Active cancer (receiving antimitotic treatment, diagnosed in past 6 months, recurrent, metastatic or inoperable
  
  • Consider a DOAC
  • if a DOAC is not suitable, consider one of:
    • LMWH
    • LMWH and a VKA for at least 5 days or until INR at least 2.0 on 2 consecutive readings, then a VKA alone
  • Offer anticoagulation for 3 to 6 months. Take into account tumour site, drug interactions including cancer drugs, and bleeding risk
• Antiphospholipid syndrome (triple positive, established diagnosis)
  • Offer LMWH and a VKA for at least 5 days or until INR at least 2.0 on 2 consecutive readings, then a VKA alone

Notes (4):

• PE with haemodynamic instability - Offer continuous UFH infusion and consider thrombolytic therapy
• Body weight
  • if body weight <50 kg or >120 kg consider anticoagulant with monitoring of therapeutic levels.
    Note cautions and requirements for dose adjustments and monitoring in SPCs. Follow local protocols, or specialist or MDT advice
• INR monitoring
  • Do not routinely offer self-management or self-monitoring of INR
• Prescribing in renal impairment and active cancer
  • some LMWHs are off label in renal impairment, and most anticoagulants are off label in active cancer
• Follow GMC guidance on prescribing unlicensed medicines
• Treatment failure
  • If anticoagulation treatment fails:
    • check adherence
    • address other sources of hypercoagulability
    • increase the dose or change to an anticoagulant with a different mode of action

References:

1. Streiff MB et al. Guidance for the treatment of deep vein thrombosis and pulmonary embolism. J Thromb Thrombolysis. 2016;41(1):32-67.
2. Mazzolai L et al. Diagnosis and management of acute deep vein thrombosis: a joint consensus document from the European society of cardiology working groups of aorta and peripheral circulation and pulmonary circulation and right ventricular function. Eur Heart J. 2017 Feb 17.
3. Wang K-L, Chu P-H, Lee C-H, et al. Management of Venous Thromboembolisms: Part I. The Consensus for Deep Vein Thrombosis . Acta Cardiologica Sinica. 2016;32(1):1-22
4. NICE. Venous thromboembolic diseases: diagnosis, management and thrombophilia testing. NICE guideline NG158. Published: 26 March 2020. Last updated: 02 August 2023