ObjectivesThe anticoagulation strategy of switching to rivaroxaban after one week of initial low-molecular-weight heparin (LMWH) therapy is recommended by a guideline for the treatment of acute iliofemoral deep vein thrombosis (DVT). However, the initial rivaroxaban dose in the switching strategy, as well as the effectiveness and safety of the early switching(less than one week )to rivaroxaban, remain inadequately substantiated. We aimed to evaluate the effectiveness and safety of early switching from LMWH to maintenance therapy of rivaroxaban (20 mg once daily) for acute iliofemoral DVT. MethodsA retrospective cohort study was conducted using data from patients with acute iliofemoral DVT who received initial LMWH anticoagulation followed by rivaroxaban maintenance therapy. The clinical outcomes were compared between early (LMWH course ≤ 7 days) and routine (LMWH course > 7 days) switching strategies within 3 months of initiating anticoagulation. Results217 patients were included, 59 (27.2%) receiving early switching and 158 (72.8%) receiving routine switching. Compared with routine switching, patients with early switching had a significantly shorter hospital stay (7 days vs. 14 days, p < 0.001). The length of hospital stay was significantly positively correlated with the duration of LMWH (r = 0.762, p < 0.001). The incidences of recurrent venous thromboembolism (5.1% vs. 2.5%, p = 0.606), major bleeding (0% vs. 1.9%, p = 0.564), clinically relevant non-major bleeding (1.7 % vs. 2.5%, p = 1.000) and all-cause mortality (6.8 % vs. 2.5%, p = 0.283) were not statistically different between the two groups. ConclusionsDirect early switching from LMWH to maintenance therapy of rivaroxaban is effective and safe for acute iliofemoral DVT.