Use of Direct Oral Anticoagulation for Isolated Distal Deep Vein Thrombosis in Japanese Orthopedic Patients

Objectives: Although direct oral anticoagulants (DOAC) have become widely used, little is known about the efficacy of DOAC for isolated distal deep vein thrombosis (DVT). Methods: In-hospitalized orthopedic patients with isolated distal DVT who were diagnosed from 2016 to 2018 were enrolled and were followed for 1 year. Embolic events included symptomatic pulmonary embolism (PE) and DVT extension above the knee. Bleeding events were determined in the presence of bleeding academic research consortium (BARC) 2, 3 or 5 bleeding. Results: Of 196 orthopedic patients, 84% of patients (n = 164) received DOAC (DOAC+ group), whereas 16% of patients (n = 32) did not (DOAC- group). Cumulative incidence of embolic events was observed in 1.5% of the DOAC+ group and none of the DOAC- group (p = 0.443). Cumulative incidence of bleeding events was observed in 5.1% of the DOAC+ group and none of the DOAC- group (p = 0.157). The majority of bleeding events (80%) occurred in patients with HAS-BLED scores of 3 or greater. Conclusions: There were no significant differences in embolic events and bleeding events in retrospective data. Balancing thrombotic risk and bleeding risk remains to be key for isolated distal DVT.