Definition: Post deep vein thrombosis syndrome is a series of syndromes such as swelling, pain, skin pigmentation and even skin refractory ulcers caused by venous obstruction and impaired deep vein valve function after deep vein thrombosis, resulting in long-term venous hypertension and impaired venous return to the limb. Typical symptoms and signs: The typical symptoms of PTS are swelling and swelling of the limbs, pain, heaviness, and easy fatigue, which are obvious when standing up. Long-term venous hypertension and venous reflux disorders can cause impaired blood circulation in the skin of the lower extremities, resulting in tissue malnutrition, manifested as skin pigmentation, dry and thickened skin, and subcutaneous fibrous tissue hyperplasia. The progression of the disease can also cause venous claudication and refractory skin ulcers, which can seriously affect the quality of life and even loss of work capacity. Incidence: Even after regular anticoagulation treatment, the incidence of PTS after acute DVT is still 25%-50%. Treatment: 1, conservative treatment: medical elastic stockings, intravenous active drugs, intermittent compression therapy of limbs and functional exercise of limbs; 2, endoluminal treatment, opening of occluded veins; 3, venous valve repair surgery. Medical compression stockings: Medical compression stockings are an important means of administering compression therapy. They have long been considered effective in the prevention and treatment of PTS. The thigh-length stockings or below-knee stockings are more effective in preventing PTS. Choice of medication: In clinical practice, medications such as mydriasis and rutin and flavonoids are commonly used to reduce the symptoms of PTS and chronic venous insufficiency, and their efficacy has been confirmed in clinical studies. As a pharmacological treatment measure for chronic venous insufficiency, Mezrin can improve blood circulation and increase venous tone, and its efficacy and safety are comparable to compression therapy. Interventional endoluminal treatment of PTS: Venous obstruction after DVT is one of the important pathogenesis of PTS, with the advancement of endoluminal technology. The treatment of diseased vessels and opening of occluded iliac vena cava by endoluminal means to relieve venous compression caused by May-Thumer syndrome is gradually becoming one of the important means to effectively relieve chronic venous hypertension after DVT and treat PTS. The opening of the iliac vena cava not only helps to resolve the obstruction of the venous outflow tract and restore venous blood flow, but also improves the function of the calf vein pump, improves the symptoms of PTS, promotes the healing of venous ulcers, and improves the quality of life of patients. The medium- and long-term efficacy of iliac vena cava stenting is satisfactory. And its long-term patency rate is also confirmed by clinical studies, with the first and second stage patency rates of 6l%-78% and 80%-95%. Venous valve repair surgery: In cases of severe PTS with predominantly valvular regurgitation, autologous valve transplantation and valve transposition are treatments worth considering.