Determinants of early and long-term efficacy of catheter-directed thrombolysis in proximal deep vein thrombosis.

PURPOSE Catheter-directed thrombolysis (CDT) for proximal deep vein thrombosis (DVT) effectively enhances clot removal and recently has been shown to reduce the development of postthrombotic syndrome (PTS). This study was performed to identify potential markers for early and long-term efficacy of CDT, adverse events, and their interrelationship. MATERIALS AND METHODS Patients aged 18-75 years (mean, 54 y; 33 women) with first-time proximal DVT and symptoms up to 21 days were included in subanalyses in an open, multicenter, randomized, controlled trial. Early efficacy was assessed with a thrombus score based on daily venography. Six-month and 2-year follow-up included iliofemoral patency assessed with duplex ultrasound and air plethysmography, and PTS was assessed with the Villalta scale. RESULTS A mean clot resolution of 82%±25 was achieved in 92 patients. Successful lysis (ie,≥50%) was obtained in 83 patients. Early efficacy was equal for femoral and iliofemoral thrombus and not related to thrombus load before CDT, symptom duration, or predisposing risk factors. Lower thrombus score at completion of CDT was associated with increased patency at 24 months (P = .040), and increased patency after 6 and 24 months was correlated with reduced development of PTS after 24 months (P<.001). Bleeding complications were mainly related to the puncture site, and popliteal vein access led to fewer bleeding incidents. CONCLUSIONS Comp, this is a Clinical Study article, so, as noted on the TOC, the Conclusions section of the abstract gets listed on the TOC. CDT via popliteal access was safe, effectively removed clots, and restored iliofemoral patency. Preprocedure evaluation did not identify patients who did not benefit from treatment. Early efficacy and follow-up patency are of importance to reduce the risk for PTS.