Advanced management of acute iliofemoral deep venous thrombosis: emergency department and beyond.

Pollack, Charles V

Recent attention to the increasing incidence of venous thromboembolism has included a call to action from the surgeon general and new guidelines from various specialty organizations. The standard of care for treatment of deep venous thrombosis in the emergency department (ED), supported by the 2008 American College of Chest Physicians (ACCP) guidelines, involves initiation of anticoagulation with low-molecular-weight heparin, pentasaccharide, or unfractionated heparin. For selected appropriate patients with extensive acute proximal deep venous thrombosis, the ACCP guidelines now recommend thrombolysis in addition to anticoagulation to reduce not only the risk of pulmonary embolism but also the risk of subsequent postthrombotic syndrome and recurrent deep venous thrombosis. Postthrombotic syndrome is a potentially debilitating chronic cluster of lower-extremity symptoms occurring in 20% to 50% of deep venous thrombosis patients subsequent to the acute insult, sometimes not until years later. A strategy of early thrombus burden reduction or frank removal might reduce the incidence of postthrombotic syndrome, as per natural history studies, venous thrombectomy data, observations after systemic and catheter-directed thrombolysis, and the still-limited number of randomized trials of catheter-directed thrombolysis (with anticoagulation) versus anticoagulation alone. Contemporary invasive (endovascular) treatments mitigate the drawbacks historically associated with thrombolytic approaches by means of intrathrombus delivery of drugs with greater fibrin specificity and lower allergenicity, followed by mechanical dispersion to accelerate lysis and then aspiration of remaining drug and clot debris. With a 2016 target completion date, the National Heart, Lung, and Blood Institute--sponsored Acute Venous Thrombosis: Thrombus Removal With Adjunctive Catheter-Directed Thrombolysis trial is comparing the safety and efficacy, in terms of both deep venous thrombosis and postthrombotic syndrome parameters, of the most evolved pharmacomechanical catheter-directed thrombolysis devices versus standard anticoagulation therapy alone. This article reviews the grounds for use of adjunctive thrombolysis in patients with acute proximal deep venous thrombosis and begins to identify types of deep venous thrombosis patients encountered in the ED who might benefit most from multidisciplinary consideration of early referral for possible endovascular therapy.