One of the most common causes of free flap compromise is microvascular thrombosis. Factors contributing to zone 1 thromboses include anastomotic irregularities, suture material and platelet adhesion. This often presents in the early postoperative period. Zone 2 however, is less well described and is associated with diffuse microvascular ischaemia. Often, these cases are associated with the use of vein grafts in a delayed reconstructive setting, and present relatively late in their postoperative follow up.

We describe the successful use of catheter-directed endovascular urokinase in revascularizing two free flaps which presented in the late postoperative setting.