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Updated: Jan 30, 2026

A Multicenter MRI Protocol for the Evaluation and Quantification of Deep Vein Thrombosis
Published on: June 2, 2015
Pharmacomechanical Catheter-Directed Thrombolysis in Acute Femoral-Popliteal Deep Vein Thrombosis: Analysis from a
Clive Kearon1, Chu-Shu Gu2, Jim A Julian2
1Department of Medicine, McMaster University, Hamilton, Ontario, Canada.
Background And Objectives:
The Acute Venous Thrombosis: Thrombus Removal with Adjunctive Catheter-Directed Thrombolysis (ATTRACT) trial reported that pharmacomechanical catheter-directed thrombolysis (PCDT) did not reduce post-thrombotic syndrome (PTS), but reduced moderate-to-severe PTS and the severity of PTS symptoms. In this analysis, we examine the effect of PCDT in patients with femoral-popliteal deep vein thrombosis (DVT) (without involvement of more proximal veins).
Patients And Methods:
Within the ATTRACT trial, 300 patients had DVT involving the femoral vein without involvement of the common femoral or iliac veins and were randomized to receive PCDT with anticoagulation or anticoagulation alone (no PCDT). Patients were followed for 24 months.
Results:
From 6 to 24 months, between the PCDT versus no PCDT arms, there was: no difference in any PTS (Villalta scale ≥ 5: risk ratio [RR] = 0.97; 95% confidence interval [CI], 0.75-1.24); moderate-or-severe PTS (Villalta scale ≥ 10: RR = 0.93; 95% CI, 0.57-1.52); severity of PTS scores; or general or disease-specific quality of life (p > 0.5 for all comparisons). From baseline to both 10 and 30 days, there was no difference in improvement of leg pain or swelling between treatment arms. From baseline to 10 days, major bleeding occurred in three versus none (p = 0.06) and any bleeding occurred in eight versus two (p = 0.032) PCDT versus no PCDT patients. Over 24 months, recurrent venous thromboembolism occurred in 16 PCDT and 12 no PCDT patients (p = 0.24).
Conclusion:
In patients with femoral-popliteal DVT, PCDT did not improve short- or long-term efficacy outcomes, but it increased bleeding. Therefore, PCDT should not be used as initial treatment of femoral-popliteal DVT. (NCT00790335).
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