PROfunda Femoris Vein Thrombosis Evaluation and Clearance to Improve Outcomes of Endovascular Treatment for Acute Iliofemoral Deep Vein Thrombosis

Inclusion Criteria: 1. Age ≥ 18 years and ≤ 85 years; 2. Diagnosed with acute iliofemoral DVT involving iliac vein, common femoral vein, and the proximal segment (orifice) of PFV (confirmed by preoperative ultrasound, CT venography, or pre-procedural venography); 3. Time from symptom onset to endovascular treatment ≤ 14 days; 4. Patient receives endovascular treatment with rapid endovascular thrombus removal device; 5. Patient provides written informed consent. Exclusion Criteria: 1. Presence of pre-existing PTS in the limb scheduled for treatment, or a history of symptomatic DVT in the same limb; 2. Concurrent symptomatic acute DVT involving the iliac vein and/or common femoral vein in the contralateral limb; 3. Known allergy to heparin, low-molecular-weight heparin, contrast media, or other relevant agents; 4. Concomitant severe pulmonary embolism with hemodynamic compromise, such as hypoxia or hypotension; 5. Intolerance to endovascular intervention due to concurrent acute systemic illness, severe dyspnea, or other contraindications; 6. Concomitant severe renal insufficiency with creatinine clearance \< 30 ml/min; 7. Presence of active bleeding, severe hepatic insufficiency, bleeding diathesis, or other coagulation disorders; 8. Concomitant severe anemia (hemoglobin \< 8.0 mg/dL) or thrombocytopenia (platelet count \< 80,000/mL); 9. History of subarachnoid hemorrhage, intracranial hemorrhage, intracranial vascular malformation, or intracranial aneurysm; 10. Pregnancy; 11. Presence of other diseases (e.g., advanced malignancy, cardiac insufficiency) with an estimated life expectancy \< 24 months; 12. Participation in another clinical trial of a drug or medical device within the past 1 month that may interfere with the present study; 13. Unwillingness to participate in this trial.