Retrospective Observational Study on Diagnosis and Treatment Trends of DVT in Japan: Japanese Vein Study XXVI.

Objectives: The introduction of direct oral anticoagulants (DOACs) has significantly changed the management of deep vein thrombosis (DVT) in Japan. This study aimed to elucidate recent trend0s in the diagnosis and management of DVT following this shift. Methods: This retrospective observational study involved 154 patients with acute and subacute DVT, and 96 patients with chronic or unknown-onset DVT, diagnosed between October 1 and 31, 2020, across 29 institutions affiliated with the Japanese Society of Phlebology. Data included patient demographics, diagnostic modalities, thrombus location, treatments, and clinical outcomes. Results: The mean age was 70.0 years, and 57.8% of patients were female. Duplex ultrasonography was the predominant diagnostic modality (96.1%). DOACs were prescribed in 64.9% of patients, replacing warfarin and heparin. Compression therapy was used in 41.6% of patients. Soleal vein thrombosis was significantly more common in isolated distal DVT (right: 50.6% vs. 30.0%, p = 0.0082; left: 66.3% vs. 35.2%, p = 0.0001). Major bleeding occurred in 3.2% of patients. Post-thrombotic syndrome was observed in 0.6% of patients with acute/subacute DVT and 12.0% of those with chronic DVT patients. Conclusions: Since the introduction of DOACs, DVT management in Japan has evolved considerably. Periodic multicenter surveys would be beneficial for evaluating long-term outcomes, treatment safety, and evolving clinical practices.