Accuracy of contralateral Villalta score to assess for pre-existing chronic venous insufficiency in patients with unilateral deep vein thrombosis.

In our study of patients with a first unilateral proximal DVT, the proportion of patients with PTS who had a cl-VS > 4 is modest. However, cl-VS appears to be stable over time. Its assessment could constitute a simple way of documenting preexisting PVI and help to classify patients as having PTS.