De-escalated rivaroxaban in postoperative isolated distal deep vein thrombosis: a propensity score–matched study

Background In postoperative isolated distal deep vein thrombosis (IDDVT), anticoagulation intensity is frequently constrained by bleeding risk, which may compromise treatment continuity and clinical effectiveness. Objectives To compare the effectiveness and safety of a de-escalated (rivaroxaban 10 mg once daily) versus standard-maintenance rivaroxaban regimen for postoperative IDDVT in a real-world surgical cohort. Methods This single-center retrospective cohort study included patients diagnosed with IDDVT following urological surgery between 2013 and 2025. Patients received rivaroxaban at either a low maintenance dose (10 mg once daily) or a standard maintenance dose (20 mg once daily) according to routine clinical practice. Propensity score matching (1:1) was applied to balance baseline characteristics, incorporating surgical approach (endoscopic vs. major structural procedures) as a surrogate for surgical trauma and bleeding risk. The primary outcome was thrombus progression to proximal deep vein thrombosis or pulmonary embolism. Secondary outcomes included IDDVT resolution and clinically relevant non-major bleeding (CRNMB). Competing-risk analyses were performed. Results After matching, 152 patients were included (76 per group). Thrombus progression did not differ significantly between groups (subdistribution hazard ratio [SHR] 1.29; 95% CI 0.48–3.46; P = 0.613). No statistically significant difference in IDDVT resolution was detected between the two groups (SHR 0.93; 95% CI, 0.64–1.36; P = 0.721). The low-dose regimen was associated with a significantly lower risk of CRNMB (HR 0.31; 95% CI, 0.11–0.85; P = 0.023) and fewer early bleeding-related treatment interruptions. Early postoperative hematuria was more frequent in the standard-dose group. Conclusions In this single-center retrospective cohort of patients with isolated distal deep vein thrombosis after urological surgery, low-dose rivaroxaban (10 mg once daily) was associated with a lower incidence of clinically relevant non-major bleeding than 20 mg once daily. No statistically significant differences were detected between regimens in thrombus progression or complete thrombus resolution. However, these findings should not be interpreted as evidence of equivalent antithrombotic efficacy, given nonrandomized treatment allocation, residual confounding, limited sample size, and wide confidence intervals for thrombotic outcomes. The results are hypothesis-generating and support studies—preferably randomized non-inferiority trials—to determine whether dose de-escalation can provide an acceptable balance between thrombotic protection and bleeding risk in postoperative patients.