Perivenous Dexamethasone Therapy: Examining Reduction of Inflammation After Thrombus Removal to Yield Benefit in Subacute and Chronic Iliofemoral DVT

Inclusion Criteria:

1. Provision of signed and dated informed consent form prior to receiving anynon-standard of care, protocol-specific procedures.
2. Stated willingness to comply with all study procedures including completion ofquestionnaires and follow-up visits and availability for the duration of the study.
3. Male or female, aged 18 to 89 years.
4. For females of reproductive potential: negative pregnancy test ≤7 days before theprocedure, use of highly effective contraception for at least 1 month prior toscreening, and agreement to use such a method during study participation.
5. Negative COVID-19 test result within 5 days prior to procedure or evidence of COVID-19vaccine or booster within past 12 months.
6. Onset of DVT symptoms 14 to 60 days prior to intervention in the study limb with needfor stenting of the iliofemoral segment.
7. Ability to take oral medication and be willing to adhere to the prescribedanti-coagulant regimen.
8. Prescription for at least 14 days low molecular weight heparin followed by therapeuticanticoagulant of investigator's choice for 12-month minimum as part ofpost-interventional medication regimen.
9. Minimum of 30 days of prescribed antiplatelet agent (aspirin or P2Y12 inhibitor).
10. Hemodynamically significant DVT (>50% area obstruction) spanning at least (a) theiliofemoral and common femoral veins or (b) the common femoral vein with extensioninto the femoral vein and/or profunda vein. Extent of thrombus in the popliteal andcalf veins is allowed.
11. Successful recanalization of the target vein with at least one patent inflow vein (femoral or profunda).

Exclusion Criteria:

1. Current enrollment in another non-registry clinical study of systemic drug therapy oranother device study that has not completed its primary endpoint, including priorenrollment in this study. Concurrent enrollment in registry studies of approveddevices or drugs are acceptable.
2. Lack of capability of understanding the nature, significance and implications of theclinical trial.
3. Body Mass Index > 40 kg/m2.
4. Non-ambulatory status prior to DVT occurrence.
5. In the target vein segment: previously treated symptomatic DVT within the previous 12months.
6. In the contralateral (non-study) leg: symptomatic DVT that, in the opinion of theoperating physician, will require surgery in the following 30 days.
7. Limb-threatening circulatory compromise with ankle-brachial index <0.4, absolute anklepressure <50 mmHg or absolute toe pressure <30 mmHg.
8. Pulmonary embolism (PE) defined as either massive (Systolic blood pressure < 90 mmHgand/or patient on IV vasoactive medication to support blood pressure), or intermediatehigh-risk PE, as defined by the European Society Guideline on management of PE.Low-risk PE and/or intermediate low-risk PE can be enrolled.
9. Inability to tolerate contemporary venous intervention procedure due to severe dyspneaor acute systemic illness.
10. Allergy, hypersensitivity, or thrombocytopenia from heparin, Recombinant tissueplasminogen activator (rtPA), dexamethasone sodium phosphate or iodinated contrast,except for mild-moderate contrast allergies for which steroid pre-medication can beused.
11. History of, or active heparin-induced thrombocytopenia (HIT).
12. Haemoglobin < 9.0 mg/dl, INR > 1.6 before starting anticoagulation, or platelets < 100,000/ml. Moderate renal impairment in diabetic patients (estimated glomerularfiltration rate < 60 ml/min) or severe renal impairment in non-diabetic patients (estimated glomerular filtration rate < 30 ml/min).
13. Active bleeding, recent (< 3 mo) GI bleeding, severe liver dysfunction, bleedingdiathesis.
14. Recent (< 3 mo) internal eye surgery or haemorrhagic retinopathy; recent (< 10 days)major surgery, cataract surgery, trauma, cardiopulmonary resuscitation, obstetricaldelivery, or other invasive procedure.
15. History of hemorrhagic stroke or intracranial/intraspinal bleed, tumor, vascularmalformation, aneurysm.
16. Active cancer with a life expectancy of <2 years.
17. Severe hypertension on repeated readings (systolic blood pressure > 180 mmHg ordiastolic blood pressure > 105 mmHg). This can be treated, and blood pressure must bestable before venous access is obtained (systolic blood pressure <140 mmHg).
18. Pregnant or breastfeeding.
19. Life expectancy < 2 years.
20. Thrombus of the inferior vena cava (IVC) extending at least one centimeter above thecommon iliac confluence.
21. Inability to obtain venous access.
22. Inability to recanalize the target vein segment(s).
23. History of ipsilateral venous stent.
24. DVT length to be targeted for perivascular drug therapy exceeds 50 cm.