Non-vitamin K oral anticoagulants (NOACs) are increasingly replacing standard vitamin K antagonists (VKAs) and/or low-molecular-weight heparins (LMWHs) for the treatment of venous thromboembolism (VTE). Although these modern agents offer some advantages (no routine monitoring required, less variability), serious concerns exist in case of bleeding, due to the need for specific monitoring and the lack of specific antidotes.
In a post-hoc analysis of the EINSTEIN studies, Eerenberg et al. compared the incidence and severity of bleeding in patients treated with either VKA/LMWH or rivaroxaban in the context of VTE. The authors observed that treatment with VKA/LMWH was associated with a higher incidence of major bleeding episodes (1.7%) than rivaroxaban (1%; HR 0.54, 95% CI 0.37-0.79). In case of major bleeding, severe clinical presentations were reported in 25% of the cases in patients treated with rivaroxaban compared to 33% with standard therapies.
Despite major concerns related to the risk of major bleeding in patients treated with NOACs, recent sub-analyses seem to confirm that treatment with NOACs is safe and associated with significantly less major bleeding compared to VKAs. However, the use of specific algorithms for the management of NOAC-associated bleeding is recommended. Such protocols should be based on standard resuscitation strategies and the use of prothrombin complex concentrates, and might be updated when specific antidotes will become routinely available.
– David Faraoni