Catheter-Directed Venous Thrombolysis in Acute Iliofemoral Vein Thrombosis (CaVenT)

Catheter-directed Venous Thrombolysis in Acute Iliofemoral Vein Thrombosis, an Open Randomized, Controlled, Clinical Trial

Deep vein thrombosis (DVT) is a severe disease, and conventional treatment with low molecular weight heparin (LMWH) and warfarin is associated with some degree of long-term sequelae, i.e. post-thrombotic syndrome (PTS). Catheter-directed thrombolytic (CDT) therapy has been introduced worldwide the last two decades. Reports have suggested a beneficial effect of this costly treatment, but there are no randomized clinical trials documenting its short- and long-term efficacy and safety. This multi-center study will randomize patients with acute iliofemoral vein thrombosis to either conventional treatment or CDT in addition to conventional treatment. Main outcome parameters are patency rates at 6 months and prevalence of PTS at 24 months. The main short-term hypothesis is that CDT of first-time acute DVT will increase patency of the affected segments after 6 months from <50% to >80%. The main long-term hypothesis is that CDT will improve long-term functional outcome, i.e. risk of PTS after 2 years from >25% to <10%.

catheter-directed continuous intravenous infusion of alteplase 0.01mg/kg/h and low-dose heparin. Max dose 20mg/24 h and up to 96 hrs.

Inclusion Criteria: Onset of symptoms <21 days Objectively verified DVT of the femoral or common iliac veins or the combined iliofemoral segment Informed consent Exclusion Criteria: Anticoagulant therapy prior to trial entry >7 days Contraindications to thrombolytic therapy Indications for thrombolytic therapy, i.e. phlegmasia coerulea dolens or vena cava thrombosis Severe anemia, hemoglobin (hgb)<8 g/dl Thrombocytopenia, platelets <80x10^9/l Severe renal failure, creatinine clearance <30ml/min Severe hypertension, systolic (syst) blood pressure (BP)>160 mmHg or diastolic (diast) BP >100 mmHg pregnancy Less than 14 days post-surgery or post-trauma History of subarachnoidal or intracerebral bleeding Disease with life expectancy <24 months Drug abuse or mental disease that may interfere with treatment and follow-up Former ipsilateral proximal DVT Chemotherapy or advanced malignant disease

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