Post-thrombotic syndrome is a common complication after acute proximal deep vein thrombosis (DVT) and is associated with reduced quality of life and a substantial cost burden. In the 2-year results of the CaVenT study, additional catheter-directed thrombolysis reduced the risk of post-thrombotic syndrome by 14% compared with conventional therapy, but did not affect quality of life. In this study we report results at the 5-year follow-up, aiming to assess whether findings for post-thrombotic syndrome and quality of life have persisted.