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)

Anticagulatant 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

Reference:

• (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 (March 2020). Venous thromboembolic diseases: diagnosis, management and thrombophilia testing.