Aspirin alone was noninferior to rivaroxaban followed by aspirin for preventing symptomatic venous thromboembolism after hip or knee arthroplasty (0.48% vs 0.45%; P<0.001 for noninferiority).
RCT (n=5,429)
Double-blind
randomized
Yes
Does aspirin alone prevent symptomatic venous thromboembolism as effectively as rivaroxaban followed by aspirin in patients after total hip or knee arthroplasty?
Aspirin alone is noninferior to a strategy of short-course rivaroxaban followed by aspirin for the prevention of symptomatic venous thromboembolism after total hip or knee arthroplasty.
Effect estimate: risk difference 0.02 percentage points (95% CI -0.34 to 0.39)
Absolute Event Rate: 0.48% vs 0.45%
p-value: p=<0.001 for noninferiority
BackgroundAspirin after an initial short course of rivaroxaban has been shown to be safe and effective for the prevention of venous thromboembolism after total hip or total knee arthroplasty, but uncertainty remains about the use of aspirin alone. MethodsIn this multicenter, double-blind, randomized, controlled trial, we assigned patients to receive once-daily thromboprophylaxis with either 81 mg of aspirin or 10 mg of oral rivaroxaban for the first 5 days after total hip or total knee arthroplasty. All the patients then received further thromboprophylaxis with 81 mg of aspirin daily for 9 additional days after knee arthroplasty and for 30 additional days after hip arthroplasty. Patients were followed for 90 days for symptomatic venous thromboembolism, which consisted of either proximal deep-vein thrombosis or pulmonary embolism (primary effectiveness outcome), and for bleeding complications (primary safety outcome). The noninferiority margin for aspirin alone as compared with rivaroxaban–aspirin was 0.7 percentage points. ResultsA total of 5429 patients underwent randomization. Venous thromboembolism developed in 13 of 2718 patients (0.48%) in the aspirin-alone group and in 12 of 2647 patients (0.45%) in the rivaroxaban–aspirin group (risk difference, 0.02 percentage points; 95% confidence interval CI, −0.34 to 0.39; P<0.001 for noninferiority). Major bleeding or clinically relevant nonmajor bleeding events occurred in 45 of 2718 patients (1.66%) in the aspirin-alone group and in 54 of 2647 patients (2.04%) in the rivaroxaban–aspirin group (risk difference, −0.38%; 95% CI, −1.11 to 0.34). ConclusionsAfter total hip and total knee arthroplasty, the use of aspirin alone was not inferior to a strategy of using rivaroxaban followed by aspirin for the prevention of symptomatic venous thromboembolism, with no clinically relevant difference in bleeding events. (Funded by the Canadian Institutes of Health Research; EPCAT III ClinicalTrials.gov number, NCT04075240.)
“Although ASA can be combined with an initial 5-day period of DOAC therapy after hip or knee replacement, it is uncertain if it can be used as a standalone prophylaxis regimen in such patients. Two large ongoing trials, EPCAT-3 and PEPPER, are addressing this question.”
Shivakumar et al. (Sun,) conducted a rct in Total hip or total knee arthroplasty (n=5,429). Aspirin alone vs. Rivaroxaban 10 mg once-daily for 5 days followed by aspirin 81 mg daily was evaluated on Symptomatic venous thromboembolism (proximal deep-vein thrombosis or pulmonary embolism) (risk difference 0.02 percentage points, 95% CI -0.34 to 0.39, p=<0.001 for noninferiority). Aspirin alone was noninferior to rivaroxaban followed by aspirin for preventing symptomatic venous thromboembolism after hip or knee arthroplasty (0.48% vs 0.45%; P<0.001 for noninferiority).