The most commonly affected superficial veins are the long (great) and short saphenous veins of the leg. Referral for investigation should not normally be necessary for a short segment of below knee SVT unless concomitant DVT is suspected.

Patients referred for suspected DVT should be assessed in the usual way for an underlying DVT: if during this investigation the SVT is adjacent to (within 3 cm of) the saphenofemoral junction (SFJ) then therapeutic anticoagulation is required for a 3 month period as there is a high risk of progression to DVT.

Otherwise SVT is a benign and self-limiting condition and in the past has been treated with NSAIDs. Although reasonable for mild cases, it has become recognised that for more symptomatic cases there is a better response to anticoagulation.

It is suggested that mild SVT (less than 5 cm in length) can be treated with non-steroidal anti-inflammatory drugs (NSAIDs). If there is no improvement after a week, then it may be better to switch to prophylactic dose dalteparin (5000 units SC daily) for 4 weeks.

If more than 5 cm in length, or treating a large distended thrombosed varicosity, it may be better treated with low molecular weight heparin for 4-6 weeks. In NHS Lothian it is advised to prescribe a treatment dose of dalteparin (200 units/kg subcutaneously daily) for 4-6 weeks duration.

It is important to offer a 1 week review to the patients after commencing treatment to ensure no worsening or extension.

Compression therapies:

Patients should be examined for foot pulses and, if present, patients may be offered Class 1 compression stockings, which may help symptoms. Patients without detectable foot pulses do not need compression. ABPI measurement is not required.

Patients with two or more episodes of thrombophlebitis of the proximal long or short saphenous veins should be referred to the Vascular Service electively.