Diagnosing DVT and PE

In patients with signs or symptoms of DVT and / or PE:1

  • National Institute for Health and Care Excellence (NICE) guidelines recommend an assessment of general medical history and a physical examination to exclude other causes1

In patients with a suspected DVT and / or PE:2

  • NICE guidelines recommend following diagnostic pathways and completing all diagnostic investigations within 24 hours of first clinical suspicion2

An interactive version of the full NICE pathway for diagnosing VTE is available here.1

Two-level DVT and PE Wells scores

The two-level DVT Wells score is a clinical prediction rule for estimating the probability of DVT and an important step in the diagnostic pathway. Patients who score 2 points or more are likely to have DVT and those with 1 point or less are unlikely.3,4

The two-level PE Wells score is used for estimating the probability of a PE. Patients who score more than 4 points are likely to have a PE and those with 4 points or less are unlikely.4

The tables below show the two-level Wells scores.

Clinical Model for Predicting the Pretest Probability of Deep-Vein Thrombosis4
Clinical Feature Points
Active cancer (treatment ongoing, within 6 months, or palliative)1
Paralysis, paresis or recent plaster immobilisation on the lower extremities1
Recently bedridden for 3 days or more, or major surgery within 12 weeks requiring general or regional anaesthesia1
Localised tenderness along the distribution of the deep venous system1
Entire leg swollen1
Calf swelling at least 3 cm larger than asymptomatic side1
Pitting oedema confirmed to the symptomatic leg1
Collateral superficial veins (non-varicose)1
Previously documented DVT1
An alternative diagnosis is at least as likely as DVT-2
Clinical Model for Predicting the Pretest Probability of Pulmonary Embolism4
Clinical FeaturePoints
Clinical signs and symptoms of DVT (minimum of leg swelling and pain with palpitation of the deep veins)3
An alternative diagnosis is less likely than PE3
Heart rate >100 beats per minute1.5
Immobilisation for more than 3 days or surgery in the previous 4 weeks1.5
Previous DVT / PE1.5
Malignancy (on treatment, treated in the last 6 months, or palliative)1

Adapted from NICE CG144, 2012.4

Risk stratification in PE

Initial risk stratification for patients with acute PE is based on clinical symptoms and signs of haemodynamic instability, which indicate a high risk of early death.5 In patients with PE who present without haemodynamic instability, further risk stratification requires assessment of two prognostic criteria:5

  1. Clinical, imaging, and laboratory indicators of PE severity, mostly related to presence of right ventricular (RV) dysfunction
  2. Presence of comorbidity and any other aggravating conditions that may adversely affect early prognosis

PE can therefore be stratified into high-risk or non-high-risk levels of early (in-hospital or 30 day) death, determining the optimal diagnostic strategies and initial management.5

Classification of PE severity and the risk of early (in-hospital or 30 day) death5
Early mortality risk Indicators of risk
Haemodynamic instability* Clinical parameters of PE severity and / or comorbidity: PESI class III–V or sPESI≥1 RV dysfunction on TTE or CTPA Elevated cardiac troponin levels
High + (+) + +
Intermediate High + + +
Low + One (or none) positive
Low Assessment optional; if assessed, negative

Adapted from Konstantinides S et al. Eur Heart J 2019.5

* One of the following clinical presentations: cardiac arrest, obstructive shock, or persistent hypotension.
† Haemodynamic instability, combined with PE confirmation on computed tomography pulmonary angiography (CTPA) and / or evidence of RV dysfunction on transthoracic echocardiogram (TTE), is sufficient to classify a patient into the high-risk PE category. In these cases, neither calculation of the Pulmonary Embolism Severity Index (PESI) nor measurement of troponins or other cardiac biomarkers is necessary.
‡ Signs of RV dysfunction on TTE (or CTPA) or elevated cardiac biomarker levels may be present, despite a calculated PESI of I–II or an sPESI of 0. Until the implications of such discrepancies for the management of PE are fully understood, these patients should be classified into the intermediate-risk category.


  • CTPA = Computed Tomography Pulmonary Angiography
  • DVT = Deep Vein Thrombosis
  • NICE = National Institute for Health and Care Excellence
  • PE = Pulmonary Embolism
  • PESI = Pulmonary Embolism Severity Index
  • RV = Right Ventricular
  • TTE = Transthoracic Echocardiogram
  • VTE = Venous Thromboembolic Events

  1. National Institute for Health and Care Excellence. Diagnosing venous thromboembolism in primary, secondary and tertiary care (NICE Pathways). 2019. Available at: https://pathways.nice.org.uk/pathways/venous-thromboembolism/diagnosing-venous-thromboembolism-in-primary-secondary-and-tertiary-care (accessed December 2019).
  2. National Institute for Health and Care Excellence. Venous thromboembolism in adults: diagnosis and management. London: NICE, 2016. Available at: www.nice.org.uk/guidance/qs29/chapter/list-of-quality-statements (accessed December 2019).
  3. National Institute for Health and Care Excellence. Venous thromboembolic diseases: diagnosis, management and thrombophilia testing (CG144). London: NICE, 2012. Available at: www.nice.org.uk/guidance/cg144 (accessed December 2019).
  4. National Institute for Health and Care Excellence. Venous thromboembolic diseases: the management of venous thromboembolic diseases and the role of thrombophilia testing (CG144) Two-level Wells score: templates for deep vein thrombosis and pulmonary embolism. London: NICE, 2012. Available at: www.nice.org.uk/guidance/cg144/resources/twolevel-wells-score-templates-for-deep-vein-thrombosis-and-pulmonary-embolism-msword-186721165 (accessed December 2019).
  5. Konstantinides S, Meyer G, Becattini C, et al. 2019 ESC Guidelines for the diagnosis and management of acute pulmonary embolism developed in collaboration with the European Respiratory Society: The Task Force for the diagnosis and management of acute pulmonary embolism of the European Society of Cardiology. Eur Heart J 2019;00:1–61. Available at: https://doi.org/10.1093/eurheartj/ehz405; PMID: 31473594.

December 2019