Deep Vein Thrombosis
Conditions
Keywords
Deep venous thrombosis, Percutaneous mechanical thrombectomy, Post-thrombotic syndrome, Profunda femoris vein
Brief summary
Patients with iliofemoral vein thrombosis are prone to developing post-thrombotic syndrome (PTS). The profunda femoris vein (PFV) is an important inflow of the iliofemoral vein. Profunda femoris vein thrombosis clearance (PFV-TC) may improve the patency of iliofemoral vein and reduce the occurrence of PTS.
Detailed description
Acute lower extremity deep vein thrombosis (DVT) can lead to obstruction of veins, causing sudden lower limb swelling. Patients may also develop post-thrombotic syndrome (PTS) manifesting as recurrent lower limb swelling, skin disorders, and even non-healing ulcers, which severely affects the patient's quality of life. Among lower extremity DVT, thrombosis involving the iliofemoral veins is the most severe, with an incidence of PTS as high as 20%-50%. Percutaneous mechanical thrombectomy (PMT) utilizes mechanical aspiration to rapidly remove thrombus, relieve venous obstruction, and restore luminal patency. According to the results of a prospective clinical study, PMT can effectively improve the primary thrombus clearance rate and shorten hospital stay in patients with DVT. Among 329 patients, 192 (58.5%) achieved complete thrombus removal using the AngioJet catheter. PMT was once considered to be the first-line treatment option for DVT. However, the results of the ATTRACT study, published in 2017 in New England Journal of Medicine, sparked considerable controversy regarding the use of PMT for DVT. The ATTRACT study found that there was no significant difference in the incidence of PTS at two years after PMT compared with anticoagulation alone. Although PMT can rapidly remove thrombus, is it unable to improve the long-term outcomes for patients with DVT? According to previous studies, the primary patency rate at 12 months after PMT for acute iliofemoral venous thrombosis ranges from 77% to 85%, while the incidence of PTS at 24 months postoperatively is as high as 40%. Residual thrombus is an important cause of thrombus recurrence, re-occlusion of the vein, and poor clinical outcomes. Previous studies have primarily focused on thrombus clearance in the popliteal vein, superficial femoral vein, common femoral vein, and iliac vein, while neglecting the assessment and clearance of profunda femoris vein (PFV) thrombosis. As the PFV is an important inflow of the iliofemoral vein, whether PFV-TC can improve the patency rate and clinical outcomes of endovascular treatment for acute iliofemoral DVT remains unclear. In a preliminary study, the investigators analyzed and compared two cohorts: one receiving conventional endovascular treatment for acute iliofemoral venous thrombosis, and the other receiving conventional treatment combined with Profunda femoris vein thrombosis clearance (PFV-TC). The results showed that the 24-month patency rate of the iliofemoral vein was 90% vs. 72%, and the incidence of PTS was 11% vs. 32% (P\<0.05). These findings were published in November 2025 in European Journal of Vascular and Endovascular Surgery. This study has garnered widespread attention, and de Wolf MAF published an invited commentary on this study, acknowledging the value of this approach in the endovascular treatment of acute iliofemoral DVT. Therefore, the investigators hypothesize that PFV-TC can improve inflow and reduce the incidence of PTS for iliofemoral DVT. However, high-level evidence is still lacking. The present study is a prospective, multicenter, randomized, open-label, evaluator-blinded, 1:1 parallel-controlled clinical trial investigating PFV-TC, aiming to obtain higher-level evidence to guide endovascular treatment of acute iliofemoral DVT.
Interventions
PROCEDUREPercutaneous mechanical thrombectomy with profunda femoris vein thrombosis clearance (PMT with PFV-TC)
PMT with PFV-TC group (experimental group): Based on the control group, access is obtained via the contralateral common femoral vein using a crossover technique, or via a popliteal-profunda communicating vessel approach to PFV. The thrombus status of the PFV is assessed, and PMT is performed on the PFV thrombosis. After thrombectomy, venography is performed to evaluate the patency of the PFV. Successful PFV-TC is defined as the presence of continuous flow from the distal PFV to the CFV, including complete clearance (no residual thrombus) and partial clearance (continuous flow with residual thrombus). Conversely, the absence of continuous flow is defined as failed PFV-TC.
PROCEDUREPercutaneous mechanical thrombectomy without profunda femoris vein thrombosis clearance (PMT without PFV-TC)
An appropriate puncture approach is selected, including the ipsilateral calf vein, ipsilateral popliteal vein, or ipsilateral femoral vein. Under ultrasound guidance, a vascular sheath is inserted after puncture, and systemic heparinization is performed. Using a guidewire and catheter, the guidewire is advanced antegradely into the inferior vena cava to establish a pathway. After the pathway is established, PMT is performed using a mechanical thrombectomy device. Acceptable thrombectomy devices include commercially available mechanical aspiration thrombectomy devices such as the AngioJet catheter (Boston Scientific, USA) and the Indigo catheter (Penumbra Inc, USA). After thrombectomy, the outcome is evaluated by venography. If iliac vein stenosis greater than 50% is detected, balloon dilation is performed using a balloon matched to the normal vessel diameter. If residual stenosis remains greater than 50% after balloon dilation, stent implantation is performed.
Sponsors
RenJi Hospital
Wenzhou Central Hospital
West China Hospital
Chengdu University of Traditional Chinese Medicine
Shanghai Ninth People's Hospital Affiliated to Shanghai Jiao Tong University
Changhai Hospital
First People's Hospital of Hangzhou
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Masking description
Due to the procedure and differences in puncture access, blinding of the patients and the interventional operators during the procedure is not feasible. Therefore, the study will be conducted as an Assessor-Blind design. To minimize bias during follow-up assessments, the evaluator responsible for assessing the primary endpoint-the incidence of Post-Thrombotic Syndrome (PTS) using the Villalta score-will be strictly blinded to the patients' treatment group allocation. The blinded evaluator will conduct follow-up visits and score assessments without access to the subjects' operative records or randomization details. Measures will be implemented to ensure that subjects are instructed not to disclose their specific treatment procedure to the follow-up assessor.
Eligibility
Sex/Gender
ALL
Age
18 Years to 85 Years
Healthy volunteers
No
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 PMT; 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.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Incidence of Post-Thrombotic Syndrome (PTS) | at 24 months | Assessed by the Villalta score. The Villalta scale is the recommended tool for diagnosing and grading the severity of PTS. It is a composite score based on 11 items (5 patient-reported symptoms and 6 clinician-assessed signs), each rated from 0 (absent) to 3 (severe), yielding a total score ranging from 0 to 33. A score of 0-4 indicates no PTS, whereas a score of ≥5 or venous ulcer confirms the diagnosis of PTS. Specifically, scores of 5-9 indicate mild PTS, 10-14 indicate moderate PTS, and a score of ≥15 or venous ulcer indicates severe PTS. Higher scores reflect greater disease severity. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Rate of re-intervention | at 24 months | Assessed by documentation of clinical reintervention |
| Quality of life score | at 6, 12, and 24 months | Assessed by Venous Insufficiency Epidemiological and Economic Study Quality of Life questionnaire (VEINES-QOL). The minimum value is 0 and the maximum value is 100. Higher score means a better outcome. |
| Recurrence rate of symptomatic Deep Vein Thrombosis (DVT) | at 24 months | Assessed by symptoms combined with ultrasound examination in the ipsilateral limb |
| Incidence of PTS | at 6 and 12 months | Assessed by the Villalta score |
| Incidence of moderate-to-severe PTS | at 6, 12, and 24 months | Assessed by the Villalta score |
| Patency rate of the ipsilateral iliofemoral vein | at 12 months and 24 months | Assessed by color Doppler ultrasound |
Countries
China
Contacts
CONTACTQihong Ni
Outcome results
None listed