Veno-occlusive disease (VOD) of the liver is a common complication of BMT and is accompanied by reduced levels of natural anticoagulants and by multi-organ dysfunction. We describe two cases of clinical VOD developing after autologous BMT and accompanied by ultrasonographic features of reversed portal venous flow. In both cases the patients had decreased levels of antithrombin (AT). Once the diagnosis of VOD was made, these patients were treated with tissue plasminogen activator (tPA) and continuous infusion AT. Each patient had radiographic and clinical resolution of VOD with the therapy. This novel treatment appears to have reversed the course of VOD without the increased risk of bleeding seen in the use of heparin therapy.