The background and role of catheter-directed thrombolysis evolving procedures for acute iliofemoral deep venous thrombosis.

Minimal invasive treatment such as early endovenous thrombus removal for iliofemoral deep venous thrombosis (DVT) emerged in the end of last century. The principle is catheter-directed thrombolysis (CDT) using either plasminogen activating agents alone, as ultrasound-assisted CDT, or in combination with mechanical devices as pharmaco-mechanical CDT. The interest for this treatment modality is the high rate of post-thrombotic syndrome (PTS) with anticoagulation (AC) alone, especially after iliofemoral DVT. Recently published randomized controlled trials (RCTs) comparing early thrombus removal with AC alone, as well as non-randomized studies, have demonstrated favorable rates, or at least a decrease of moderate and severe PTS, in favor of these procedures. This article will summarize the background and evolution of the procedures in the last three decades and discuss fundamental criteria for inclusion and exclusion, focusing on the procedures regarding thrombus age and location, technical issues, complications and results including different outcome measures for PTS, for which iliac DVT involvement is a massive risk factor to be prevented.