In venous thromboembolism (VTE), a blood clot forms in a vein, usually in the deep veins of the legs or pelvis. This is known as deep vein thrombosis, or deep vein thrombosis (DVT). The blood clot can dislodge and travel in the blood, particularly to the pulmonary arteries. This is known as pulmonary embolism (PE). The term 'VTE' includes both DVT and PE.
Failure to diagnose and treat VTE correctly can result in fatal PE, in which the blood clot blocks the blood supply to the lungs. However, diagnosis of VTE is not always straightforward. This guideline includes advice on the Wells score, D-dimer measurement, ultrasound and radiological imaging. It also offers guidance on treating VTE, investigations for cancer in people with VTE and thrombophilia testing. The guideline covers adults with suspected or confirmed DVT or PE. It does not cover children or young people aged under 18, or women who are pregnant.
Since publication of the original guideline in 2012, new evidence has emerged and practice has changed in relation to the use of direct oral anticoagulants, prognostic tools, diagnosis of VTE using age-adjusted and point-of-care D-dimer testing, pulmonary embolism rule-out criteria, outpatient treatment for PE, inferior vena caval filters and investigations for cancer in people with unprovoked VTE. This 2020 update includes new and updated recommendations in these areas.