Treatment of Distal Deep Vein Thrombosis

Summary

A Cochrane review [Abstract] 1 included 8 studies with a total of 1 239 subjects with distal (below the knee) deep vein thrombosis (DVT). Five studies compared anticoagulation for up to 3 months with no anticoagulation, and 3 studies compared anticoagulation treatment for different time periods.

Anticoagulant compared to no intervention or placebo:Anticoagulation with a vitamin K antagonist (VKA) reduced the risk of recurrent venous thromboembolism (VTE) during follow-up compared with no intervention or placebo group (RR 0.34, 95% CI 0.15 to 0.77; 5 studies, n=496), and reduced the risk of recurrence of DVT (RR 0.25, 95% CI 0.10 to 0.67; 5 studies, n=496). No clear effect on risk of pulmonary embolism (PE) (RR 0.81, 95% CI 0.18 to 3.59; 4 studies, n=480) and no difference in major bleeding (RR 0.76, 95% CI 0.13 to 4.62; 4 studies, n=480) between anticoagulation therapy and no intervention or placebo was observed. An increase in clinically relevant non-major bleeding events in the group treated with anticoagulants (RR 3.34, 95% CI 1.07 to 10.46; 2 studies, n=322) was observed. There was one death, not related to PE or major bleeding, in the anticoagulation group.

Anticoagulation for 3 months or more compared to anticoagulation for 6 weeks: Anticoagulation with a VKA for 3 months or more reduced the incidence of recurrent VTE to 5.8% compared with 13.9% in participants treated for 6 weeks (RR 0.42, 95% CI 0.26 to 0.68; 3 studies, n=736), and the risk for recurrence of DVT was also reduced (RR 0.32, 95% CI 0.16 to 0.64; 2 studies, n=389), but there was little or no difference in PE (RR 1.05, 95% CI 0.19 to 5.88; 2 studies, n=389). No clear difference in major bleeding events (RR 3.42, 95% CI 0.36 to 32.35; 2 studies, n=389 participants) or clinically relevant non-major bleeding events (RR 1.76, 95% CI 0.90 to 3.42; 2 studies, n=389) were observed.