Clinical question: Is fondaparinux an effective and safe treatment for patients with acute, symptomatic superficial-vein thrombosis in the legs?

Background: Superficial-vein thrombosis of the legs is a common condition, with an estimated incidence that may exceed that of deep-vein thrombosis (DVT). Patients with superficial-vein thrombosis are at increased risk for subsequent symptomatic venous thromboembolic complications including DVT and pulmonary embolism (PE).

Study design: Industry-sponsored, randomized, double-blind placebo controlled study.

Setting: 171 hospitals and outpatient clinics in 17 countries.

Synopsis: Data were collected on 3,000 patients presenting with ultrasound-confirmed symptomatic superficial-vein thrombosis of the legs.

Compared with placebo, fondaparinux reduced the risk of the composite of DVT or PE by 85%, the risk of clot extension to the saphenofemoral junction by 92%, the need for surgery for superficial vein thrombosis by 81%, and the development of a recurrence of superficial-vein thrombosis by 79%.

The number needed to treat (NNT) to prevent one event of the primary outcomes was 20, whereas the NNT to specifically prevent DVT or a PE was 88.

The rates of clinically relevant nonmajor, minor, and total bleeding and arterial thromboembolic complications did not differ significantly between the two groups. No episodes of thrombocytopenia were reported in the fondaparinux group.

Bottom line: Fondaparinux at a dose of 2.5 mg once a day for 45 days is effective in reducing the risk DVT and PE in patients with acute, symptomatic superficial-vein thrombosis of the legs without an associated increased bleeding risk.

Citation: Decousus H, Prandoni P, Mismetti P, et al. Fondaparinux for the treatment of superficial-vein thrombosis in the legs. N Engl J Med. 2010;363(13):1222-1232.

Reviewed for TH eWire by Steven Deitelzweig, MD, MMM, SFHM, Renee Meadows, MD, SFHM, David Lee, MD, MBA, FHM, Frank Wharton, MD, FHM, Srinivas Vuppala, MD, William Carter, MD, Prasad Ravipati, MD, Department of Hospital Medicine, Ochsner Health System, New Orleans.

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