Cardiovascular Disease: Lower Extremity Deep Venous Thrombosis.

Risk factors for deep venous thrombosis (DVT) include immobility, recent or current hospitalization, recent surgery, recent infection, and cancer. Patients with suspected venous thromboembolism should be evaluated with the Wells score or modified Wells score (which adds a previous DVT) to determine the likelihood of DVT. A low or moderate probability score and a normal D-dimer test result exclude DVT. If the score indicates that DVT is likely, patients should undergo Doppler ultrasonography (US). If US reveals DVT in a proximal (ie, in the knee or above) vein, anticoagulation should be started unless contraindicated. If the DVT is distal (ie, below the knee), patients can be started on anticoagulation or monitored with repeat US and started on anticoagulation if the clot extends proximally. For anticoagulation, direct oral anticoagulants are recommended for most patients except pregnant women, for whom heparins are recommended. The treatment duration is at least 3 months, and longer if risk factors persist. Indefinite therapy may be required for patients with irreversible risk factors or inherited coagulation disorders. Other treatments, such as thrombectomy, thrombolytics, and vena cava filters, are used for select patients. Evaluation should include consideration of testing for occult cancer.