Rivaroxaban versus enoxaparin after total knee arthroplasty

Alexander Turpie and colleagues

show that rivaroxaban, an orally active, highly selective, direct inhibitor of activated factor X, given at a fixed dose of 10 mg daily, holds the promise of greatly simplifying thromboprophylaxis in patients undergoing total knee arthroplasty. However, we feel that some concerns

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remain unresolved.

The risk of venous thromboembolism after orthopaedic surgery needs to be balanced against the unstudied potential complications of anticoagulant drugs. Most studies of anticoagulant therapy investigate the efficacy and safety of a drug to prevent venous thromboembolism, but they do not take into account many surgical outcomes which normally guide an orthopaedic surgeon’s choice of anticoagulant (ie, wound healing, drainage, infection, range of motion, and chronic pain).

To date, there is no specific antidote to reverse the effects of activated factor X inhibitors.

The unpredictable off-target effects of selective anticoagulants should also be considered, since proteases such as thrombin also have a role in disorders such as atherosclerosis and cancer. Therefore long-term clinical monitoring of their effects is required.

Until all these points are answered, we suggest that the non-selective administration of rivaroxaban instead of enoxaparin for thromboprophylaxis in all patients undergoing total knee arthroplasty remains questionable.

We declare that we have no conflicts of interest.