Note on treating venous thromboembolism (VTE)

Generally recommend treating VTE with a full-dose anticoagulant for at least 3 months and up to 6 months, especially for pulmonary embolism....

Introduction

Discover key insights into managing venous thromboembolism (VTE) with our concise guide. From preferred anticoagulants to treatment duration and recurrence management, we unravel critical considerations for optimal patient care.

Which anticoagulant is preferred?
How long should anticoagulation be used?
When might a low-dose DOAC be considered long-term?
When might a low-dose DOAC be considered long-term?
What should you do if a patient has a VTE on anticoagulation?

NPS-adv

Questions and answers

Which anticoagulant is preferred?

Think of a direct oral anticoagulant (DOAC) first for most patients. These work as well as warfarin, have lower risk of major bleeding and can be easier to use. Point out that no study compares DOACs head-to-head. But suggest Eliquis (apixaban) or Xarelto (rivaroxaban).

Pradaxa (dabigatran) or Savaysa (edoxaban) needs 5 to 10 days of pretreatment with an injectable anticoagulant, such as enoxaparin.
Recommend warfarin for some patients such as most with CrCl below 30 mL/min or if cost is an issue.

How long should anticoagulation be used?

Generally, recommend treating VTE with a full-dose anticoagulant for at least 3 months and up to 6 months, especially for pulmonary embolism. But expect anticoagulation to be continued long-term for secondary VTE prophylaxis in most patients with persistent risks such as, active cancer, inflammatory bowel disease, multiple unprovoked VTEs, etc. Review benefits and risks of anticoagulation at least annually.

When might a low-dose DOAC be considered long-term?

It's an option if long-term anticoagulation is preferred in patients at MODERATE risk of VTE recurrence. This includes patients with a clot above the knee from an unknown cause or a clot from a reversible cause plus other risks (obesity, etc).

In these cases, efficacy seems similar when switching after about 6 months from Eliquis 5 mg BID to 2.5 mg BID or Xarelto 20 mg/day to 10 mg/day.
But it's too soon to say if lower doses limit bleeding. Stick with full doses for patients at HIGH risk of VTE recurrence.

What should you do if a patient has a VTE on anticoagulation?

Check for non-adherence, interactions, or inappropriate dosing. For patients on a low-dose DOAC, advise bumping up to full dose. Or if adherent warfarin patients have erratic INRs, consider a DOAC. On the other hand, if DOAC adherence is a concern, think about switching to warfarin since it can be monitored. If patients already on a full-dose DOAC or well-controlled warfarin have a breakthrough VTE, consider other causes such as, undiagnosed cancer or a clotting disorder.

NPS-adv

References

Ortel, T.L., Neumann, I., and others (2020). American Society of Hematology 2020 guidelines for management of venous thromboembolism: treatment of deep vein thrombosis and pulmonary embolism. Blood Advances, [online] 4(19), pp.4693–4738.
Agnelli, G., Buller, H.R., Cohen, A., Curto, M., Gallus, A.S., Johnson, M., Porcari, A., Raskob, G.E. and Weitz, J.I. (2013). Apixaban for Extended Treatment of Venous Thromboembolism. New England Journal of Medicine, 368(8), pp.699–708.
American College of Cardiology. Anticoagulation Among Patients Hospitalized With COVID-19. [online] Available at: https://www.acc.org/latest-in-cardiology/journal-scans/2020/08/27/14/18/anticoagulation-mortality-bleeding-and-pathology.
New England Journal of Medicine, 376(13), pp.1211–1222 Europe PMC (2019). Colchicine therapy for deep vein thrombosis in a patient with vascular-type Behçet disease: A case report. Available at: https://europepmc.org/article/pmc/pmc7220338.