Non-invasive diagnosis of venous thromboembolism in outpatients

Lancet. 1999 Jan 16;353(9148):190-5. doi: 10.1016/S0140-6736(98)05248-9.


Background: We designed a simple and integrated diagnostic algorithm for acute venous thromboembolism based on clinical probability assessment of deep-vein thrombosis (DVT) or pulmonary embolism (PE), plasma D-dimer measurement, lower-limb venous compression ultrasonography, and lung scan to reduce the need for phlebography and pulmonary angiography.

Methods: 918 consecutive patients presenting at the emergency ward of the Geneva University Hospital, Geneva, Switzerland, and Hôpital Saint-Luc, Montreal, Canada, with clinically suspected venous thromboembolism were entered into a sequential diagnostic protocol. Patients in whom venous thromboembolism was deemed absent were not given anticoagulants and were followed up for 3 months.

Findings: A normal D-dimer concentration (<500 microg/L by a rapid ELISA) ruled out venous thromboembolism in 286 (31%) members of the study cohort, whereas DVT by ultrasonography established the diagnosis in 157 (17%). Lung scan was diagnostic in 80 (9%) of the remaining patients. Venous thromboembolism was also deemed absent in patients with low to intermediate clinical probability of DVT and a normal venous ultrasonography (236 [26%] patients), and in patients with a low clinical probability of PE and a non-diagnostic result on lung scan (107 [12%] patients). Pulmonary angiography and phlebography were done in only 50 (5%) and 2 (<1%) of the patients, respectively. Hence, a non-invasive diagnosis was possible in 866 (94%) members of the entire cohort. The 3-month thromboembolic risk in patients not given anticoagulants, based on the results of the diagnostic protocol, was 1.8% (95% CI 0.9-3.1).

Interpretation: A diagnostic strategy combining clinical assessment, D-dimer, ultrasonography, and lung scan gave a non-invasive diagnosis in the vast majority of outpatients with suspected venous thromboembolism, and appeared to be safe.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Disease
  • Algorithms
  • Ambulatory Care
  • Enzyme-Linked Immunosorbent Assay
  • Fibrin Fibrinogen Degradation Products / analysis
  • Humans
  • Leg / blood supply*
  • Lung / diagnostic imaging
  • Prospective Studies
  • Pulmonary Embolism / diagnosis*
  • Pulmonary Embolism / diagnostic imaging
  • Radionuclide Imaging
  • Risk Factors
  • Ultrasonography
  • Venous Thrombosis / diagnosis*
  • Venous Thrombosis / diagnostic imaging


  • Fibrin Fibrinogen Degradation Products
  • fibrin fragment D