Medical management of acute superficial vein thrombosis of the saphenous vein.

OBJECTIVE: Acute superficial vein thrombosis (SVT) of the axial veins, such as the great saphenous vein (GSV), is a common clinical condition that carries with it significant risk of propagation of thrombus, recurrence, and, most concerning, subsequent venous thromboembolism (VTE). Conservative therapy with nonsteroidal anti-inflammatory medication and heat does not prevent extension of thrombus or protect against recurrent or future VTE in patients with extensive SVT (thrombotic segment of at least 5 cm in length). To prevent future thromboembolic events, anticoagulation has become the treatment of choice for extensive acute SVT in the GSV. In spite of this, the dose and duration of anticoagulation in the treatment of SVT vary widely. This review summarizes the evidence from large prospective, randomized clinical trials on the treatment of SVT with anticoagulation (vs placebo or different doses and durations of anticoagulation) with respect to the outcome measures of thrombus extension, SVT recurrence, and future VTE.
METHODS: A systematic search was performed using the MEDLINE database to identify all prospective, randomized controlled trials of treatment with anticoagulation in patients with SVT in the GSV. Six prospective, randomized trials were identified that met the inclusion criteria and were reviewed in detail.
RESULTS: Treatment of acute SVT was most commonly managed in an outpatient setting using either low-molecular-weight heparin (LMWH) in four studies or, alternatively, a factor Xa inhibitor in one large multicenter trial. LMWH was associated with a lower rate of thrombus extension and subsequent recurrence, especially when an intermediate dose (defined as a dose between prophylactic and therapeutic doses) was used for a period of 30 days. The full effect of treatment with LMWH on the risk of subsequent VTE remains unclear, as do the optimal dose and duration of this drug. Prophylactic doses of fondaparinux, a factor Xa inhibitor, were found to be beneficial in reducing the rate of thrombus extension and recurrence as well as in reducing the risk of subsequent VTE both during treatment and after cessation of anticoagulation in the short term.
CONCLUSIONS: These data suggest that treatment of acute SVT of the GSV with anticoagulation, at doses below therapeutic levels, does offer the benefit of decreased risk of thrombus propagation, recurrence, and, at least in one large randomized clinical trial, subsequent VTE. Future studies to refine optimal dose and duration of anticoagulation to lower the rate of subsequent thromboembolic events and SVT recurrence are needed.