Effectiveness and safety of rivaroxaban compared to enoxaparin for thromboprophylaxis in orthopedic patients

Purpose: This retrospective study compared the effectiveness and safety of rivaroxaban to enoxaparin for prophylaxis against venous thromboembolism (VTE) in patients who had undergone total hip or knee arthroplasty (THA/TKA).

Methods: The medical records of randomly selected patients who received either rivaroxaban or enoxaparin for VTE prophylaxis post THA or TKA between January 1, 2011 and March 31, 2012 were reviewed. Data was collected for a comparative analysis of baseline characteristics and primary outcomes. The primary effectiveness outcome was any post-surgical VTE event, defined as any deep vein thrombosis (DVT) or pulmonary embolism (PE) within 35 days post THA and 17 days post TKA. Safety outcomes included incidence of any post surgical hemorrhagic or non-hemorrhagic adverse events, and all cause mortality.

Results: A total of 77 patients were analyzed (50 in the enoxaparin arm and 27 in the rivaroxaban arm). Baseline characteristics were similar in both groups.  DVT or PE events occurred in none of the patients in the rivaroxaban arm and 8% (4/50) of the patients in the enoxaparin arm. Post-surgical hemorrhagic events were reported in 15% (4/27) of patients in the rivaroxaban arm and 6% (3/50) of patients in the enoxaparin group. Surgery related non-hemorrhagic adverse events were noted in 7% (2/27) in the rivaroxaban arm and none in the enoxaparin arm.   There were no reports of mortality.

Conclusions: Rivaroxaban was associated with a lower incidence of VTE in patients who had undergone THA or TKA compared to enoxaparin. There was a higher rate of post-surgical hemorrhagic and non-hemorrhagic adverse events in patients on rivaroxaban compared to enoxaparin