Comparison of the Villalta post-thrombotic syndrome score in the ipsilateral vs. contralateral leg after a first unprovoked deep vein thrombosis.

Background: Post-thrombotic syndrome (PTS) is the most frequent complication of a deep vein thrombosis (DVT). International guidelines recommend assessing PTS with the Villalta scale, a clinical measure that incorporates venous symptoms and signs in the leg ipsilateral to a DVT. However, these signs and symptoms are not specific for PTS and their prevalence and relevance in the contralateral leg have not previously been studied. Methods: Using data from the REVERSE prospective multicentre cohort study, we compared the Villalta total score and prevalence of venous signs and symptoms in the ipsilateral vs. contralateral leg in patients with a first, unilateral DVT 5 to 7 months previously. Results: Among the 367 patients analyzed, the mean Villalta score was higher in the ipsilateral than in the contralateral leg (mean +/- standard deviation [SD] 3.7 [3.4] vs. 1.9 [2.5], respectively; P < 0.0001). Villalta scores in the ipsilateral and contralateral legs were strongly correlated (r = 0.68; P < 0.0001). Ipsilateral PTS (defined by a Villalta total score > 4) was present in 31.6% (n = 116) of patients. Among these, 39.7% (n = 46) of patients had a Villalta score > 4 in the contralateral leg, and the distribution of Villalta symptoms and signs components was similar between the legs. Conclusions: Villalta scores in the ipsilateral and contralateral legs are strongly correlated. Almost half of cases considered to be PTS might reflect pre-existing symptomatic chronic venous disease. Alternatively, patients with pre-existing chronic venous disease might be more prone to developing PTS after a DVT. Performing a bilateral assessment of Villalta scores at the acute phase of DVT could be of clinical interest from a diagnostic, prognostic and therapeutic point of view.