[Postthrombotic syndrome: an update].

Postthrombotic syndrome (PTS) is the most common chronic late complication after deep vein thrombosis (DVT): approximately 20-50% develop symptoms and a severe disease course with venous ulceration occurs in roughly 5-10%. The trigger is persistent venous hypertension caused by residual obstruction from incomplete recanalization and/or valve destruction leading to reflux; inflammatory processes further damage the vein wall and valves. Clinically, patients report heaviness, pain, tightness, edema, cramps and skin changes (hyperpigmentation, eczema, lipodermatosclerosis), potentially progressing to venous ulcers. The diagnosis is primarily clinical (typically within 18-24 months after DVT) and should be assessed with the Villalta score; duplex ultrasound is the standard imaging method to evaluate obstruction and reflux, although ultrasound findings do not always correlate with symptom severity. Major risk factors include proximal/iliofemoral DVT, recurrent thrombosis, obesity and delayed or inadequate initial treatment. Prevention and first-line management focus on early and adequate anticoagulation, mobilization and consistent compression therapy (often compression classes II-III) combined with regular exercise or training; for persistent edema, adjustable compression devices or intermittent pneumatic compression can be used. In severe, refractory PTS with pelvic vein obstruction, recanalization and stenting can be considered; venous ulcers require structured wound treatment.