Outpatient management of acute deep vein thrombosis: results from the OTIS-DVT registry.

Objectives: We aimed to investigate clinical practice patterns for the outpatient management of acute deep vein thrombosis (DVT).

Methods: In the prospective Outpatient Treatment of Deep Vein Thrombosis in Switzerland (OTIS-DVT) registry, 534 consecutive outpatients with acute DVT (49% proximal, 24% recurrent, and 12% cancer-associated) were enrolled: 41% patients were managed in private angiology practice, 34% in an outpatient hospital department, and 25% in private general or internal medicine practice.

Results: For diagnosis, ultrasound was used in 95% and D-dimer testing in 53%. Low-molecular-weight heparin (LMWH) was prescribed for a median (IQR) duration of 7 (5-12) days in 83% of patients, and vitamin K-antagonists for 163 (92-183) days in 81%. Mechanical measures to prevent post-thrombotic syndrome were prescribed in 83%; compression stockings or bandages for a median (IQR) duration of 364 (101-730) days from hospital physicians, and 92 (45-183) days from private practice physicians (p < 0.001). Among patients with symptomatic proximal DVT, mechanical measures were prescribed for at least 2 years in 24% patients; 55% in hospital, and 6% in private practice (p < 0.001). Among patients with cancer-associated DVT, the median (IQR) duration of LMWH therapy was 16 (8-45) days, and 35% received LMWH for less than 90 days.

Conclusions: The OTIS-DVT registry provides representative information on clinical practice patterns for outpatients with acute DVT managed by hospital or private practice physicians. The use of mechanical measures in patients with symptomatic proximal DVT and the administration of LMWH for a long-term therapy of cancer-associated DVT require improvement to comply with current guidelines.