Abstract
Systemically delivered pharmacologic thrombolysis for acute deep vein thrombosis long ago gave way to catheter delivery of plasminogen activators within the clot. This simple concept resulted in markedly improved efficacy and safety. In an effort to accelerate thrombus dissolution or extraction, mechanical methods were developed, but the initial techniques left substantial residual thrombus that required subsequent catheter-directed thrombolysis (CDT). It was soon observed that combined pharmacomechanical thrombolysis was more effective than either one alone. Randomized trials of catheter-based strategies for thrombus removal have documented objective benefit, including improved patency, preserved valve function, and reduced post-thrombotic syndrome. The largest randomized study is the ATTRACT trial published at the end of 2017. Although mild post-thrombotic syndrome (PTS) was no different between the pharmacomechanical catheter-directed thrombolysis (PCDT) and control groups, acute pain and swelling and moderate-to-severe PTS were reduced with PCDT. Additional analyses from this robust data set are forthcoming.