Deep Venous Thrombosis and Pulmonary Embolism: Current Therapy

Abstract

Pulmonary embolism and deep venous thrombosis are the two most important manifestations of venous thromboembolism (VTE), which is the third most common life-threatening cardiovascular disease in the United States. Anticoagulation is the mainstay of VTE treatment. Most patients with deep venous thrombosis or low-risk pulmonary embolism can be treated in the outpatient setting with low-molecular-weight heparin and a vitamin K antagonist (warfarin) or direct-acting oral anticoagulants. Inpatient treatment of VTE begins with parenteral agents, preferably low-molecular-weight heparin. Unfractionated heparin is used if a patient is hemodynamically unstable or has severe renal insufficiency, high bleeding risk, hemodynamic instability, or morbid obesity. Direct-acting oral anticoagulants are an alternative; however, concerns include cost and use of reversing agents (currently available only for dabigatran, although others are in development). If warfarin, dabigatran, or edoxaban is used, low-molecular-weight or unfractionated heparin must be administered concomitantly for at least five days and, in the case of warfarin, until the international normalized ratio becomes therapeutic for 24 hours. Hemodynamically unstable patients with a low bleeding risk may benefit from thrombolytic therapy. An inferior vena cava filter is not indicated for patients treated with anticoagulation. Current guidelines recommend anticoagulation for a minimum of three months. Special situations, such as active cancer and pregnancy, require long-term use of low-molecular-weight or unfractionated heparin. Anticoagulation beyond three months should be individualized based on a risk/benefit analysis. Symptomatic distal deep venous thrombosis should be treated with anticoagulation, but asymptomatic patients may be monitored with serial imaging for two weeks and treated only if there is extension.