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Venous thromboembolic diseases: diagnosis, management and thrombophilia testing
NICE guideline [NG158] Published: 26 March 2020
This guideline covers diagnosing and managing venous thromboembolic diseases in adults. It aims to support rapid diagnosis and effective treatment for people who develop deep vein thrombosis (DVT) or pulmonary embolism (PE).
NICE has produced a visual summary of the recommendations on diagnosis and initial management of suspected deep vein thrombosis (DVT) and pulmonary embolism (PE).
Signs or symptoms of DVT
For people who present with signs or symptoms of DVT, such as a swollen or painful leg, assess their general medical history and do a physical examination to exclude other causes.
If DVT is suspected, use the 2‑level DVT Wells score (table 1) to estimate the clinical probability of DVT.
Clinical feature | Points |
|---|---|
Active cancer (treatment ongoing, within 6 months, or palliative) | 1 |
Paralysis, paresis or recent plaster immobilisation of the lower extremities | 1 |
Recently bedridden for 3 days or more, or major surgery within 12 weeks requiring general or regional anaesthesia | 1 |
Localised tenderness along the distribution of the deep venous system | 1 |
Entire leg swollen | 1 |
Calf swelling at least 3 cm larger than asymptomatic side | 1 |
Pitting oedema confined to the symptomatic leg | 1 |
Collateral superficial veins (non-varicose) | 1 |
Previously documented DVT | 1 |
An alternative diagnosis is at least as likely as DVT | -2 |
Clinical probability simplified score | Points |
DVT likely | 2 points or more |
DVT unlikely | 1 point or less |
1.1.3 Offer people with a likely DVT Wells score (2 points or more):
a proximal leg vein ultrasound scan, with the result available within 4 hours if possible (if the scan result cannot be obtained within 4 hours follow recommendation 1.1.4)
a D-dimer test if the scan result is negative.
1.1.4 If a proximal leg vein ultrasound scan result cannot be obtained within 4 hours, offer people with a DVT Wells score of 2 points or more:
interim therapeutic anticoagulation (see the section on interim therapeutic anticoagulation for suspected DVT or PE) and
a proximal leg vein ultrasound scan with the result available within 24 hours.
1.1.5 For people with a positive proximal leg vein ultrasound scan:
offer or continue anticoagulation treatment (see the section on anticoagulation treatment for confirmed DVT or PE) or
if anticoagulation treatment is contraindicated, offer a mechanical intervention (see the section on mechanical interventions).
For people with symptomatic iliofemoral DVT see the section on thrombolytic therapy.
1.1.6 For people with a negative proximal leg vein ultrasound scan and a positive D-dimer test result:
stop interim therapeutic anticoagulation (but do not stop long-term anticoagulation if being used for secondary prevention)
offer a repeat proximal leg vein ultrasound scan 6 to 8 days later and
if the repeat scan result is positive, follow the actions in recommendation 1.1.5
if the repeat scan result is negative, follow the actions in recommendation 1.1.7.
1.1.7 For people with a negative proximal leg vein ultrasound scan and a negative D-dimer test result:
1.1.8 Offer people with an unlikely DVT Wells score (1 point or less):
a D‑dimer test with the result available within 4 hours (see the section on D-dimer testing) or
if the D-dimer test result cannot be obtained within 4 hours, offer interim therapeutic anticoagulation while awaiting the result (see the section on interim therapeutic anticoagulation for suspected DVT or PE).
1.1.9 If the D-dimer test result is negative, follow the actions in recommendation 1.1.7.
1.1.10 If the D-dimer test result is positive, offer:
a proximal leg vein ultrasound scan, with the result available within 4 hours if possible or
interim therapeutic anticoagulation (see the section on interim therapeutic anticoagulation for suspected DVT or PE) and a proximal leg vein ultrasound scan with the result available within 24 hours.
1.1.11 If the proximal leg vein ultrasound scan is:
positive, follow the actions in recommendation 1.1.5
negative, follow the actions in recommendation 1.1.7, that is:
stop interim therapeutic anticoagulation (but do not stop long-term anticoagulation if being used for secondary prevention)
think about alternative diagnoses
tell the person that it is not likely they have DVT. Discuss with them the signs and symptoms of DVT and when and where to seek further medical help.
For people who present with signs or symptoms of PE, such as chest pain, shortness of breath or coughing up blood, assess their general medical history, do a physical examination and offer a chest X‑ray to exclude other causes.
If clinical suspicion of PE is low (the clinician estimates the likelihood of PE to be less than 15% based on the overall clinical impression, and other diagnoses are feasible), consider using the pulmonary embolism rule-out criteria (PERC) to help determine whether any further investigations for PE are needed.
If PE is suspected, use the 2‑level PE Wells score (table 2) to estimate the clinical probability of PE.
Clinical feature | Points |
|---|---|
Clinical signs and symptoms of DVT (minimum of leg swelling and pain with palpation of the deep veins) | 3 |
An alternative diagnosis is less likely than PE | 3 |
Heart rate more than 100 beats per minute | 1.5 |
Immobilisation for more than 3 days or surgery in the previous 4 weeks | 1.5 |
Previous DVT/PE | 1.5 |
Haemoptysis | 1 |
Malignancy (on treatment, treated in the last 6 months, or palliative) | 1 |
Clinical probability simplified score | Points |
PE likely | More than 4 points |
PE unlikely | 4 points or less |
1.1.18 For people with a likely PE Wells score (more than 4 points):
offer a computed tomography pulmonary angiogram (CTPA) immediately if possible or
for people with an allergy to contrast media, severe renal impairment (estimated creatinine clearance less than 30 ml/min) or a high risk from irradiation, assess the suitability of a ventilation/perfusion single photon emission computed tomography (V/Q SPECT) scan or, if a V/Q SPECT scan is not available, a V/Q planar scan, as an alternative to CTPA.
If a CTPA, V/Q SPECT or V/Q planar scan cannot be done immediately, offer interim therapeutic anticoagulation (see the section on interim therapeutic anticoagulation for suspected DVT or PE).
1.1.19 If PE is identified by CTPA, V/Q SPECT or V/Q planar scan:
offer or continue anticoagulation treatment (see the section on anticoagulation treatment for confirmed DVT or PE) or
if anticoagulation treatment is contraindicated, consider a mechanical intervention (see the section on mechanical interventions).
For people with PE and haemodynamic instability see the section on thrombolytic therapy.
1.1.20 If PE is not identified by CTPA, V/Q SPECT or V/Q planar scan:
consider a proximal leg vein ultrasound scan if DVT is suspected
if DVT is not suspected:
stop interim therapeutic anticoagulation (but do not stop long-term anticoagulation if being used for secondary prevention)
think about alternative diagnoses
tell the person that it is not likely they have PE. Discuss with them the signs and symptoms of PE and when and where to seek further medical help.
1.1.21 Offer people with an unlikely PE Wells score (4 points or less):
a D-dimer test with the result available within 4 hours if possible (see the section on D-dimer testing) or
if the D-dimer test result cannot be obtained within 4 hours, offer interim therapeutic anticoagulation while awaiting the result (see the section on interim therapeutic anticoagulation for suspected DVT or PE).
If the D-dimer test result is:positive, follow the actions in recommendations 1.1.18 and 1.1.19
negative:
stop interim therapeutic anticoagulation (but do not stop long-term anticoagulation if being used for secondary prevention)
think about alternative diagnoses
tell the person that it is not likely they have PE. Discuss with them the signs and symptoms of PE and when and where to seek further medical help.
For people who present with signs or symptoms of both DVT and PE, carry out initial diagnostic investigations for either DVT or PE, basing the choice of diagnostic investigations on clinical judgement.
NICE has produced a visual summary of the recommendations on anticoagulation treatment for DVT or PE.
1.3.1 When offering anticoagulation treatment, follow the recommendations on shared decision making and supporting adherence in the NICE guidelines on medicines optimisation, medicines adherence, patient experience in adult NHS services and shared decision making.
Interim therapeutic anticoagulation for suspected DVT or PE
1.3.2 Follow the recommendations on when to offer interim therapeutic anticoagulation for suspected proximal DVT or PE in the section on diagnosis and initial management.
1.3.3 If possible, choose an interim anticoagulant that can be continued if DVT or PE is confirmed (see the section on anticoagulation treatment for confirmed DVT or PE).
1.3.4 When using interim therapeutic anticoagulation for suspected proximal DVT or PE:
carry out baseline blood tests including full blood count, renal and hepatic function, prothrombin time (PT) and activated partial thromboplastin time (APTT)
do not wait for the results of baseline blood tests before starting anticoagulation treatment
review, and if necessary act on, the results of baseline blood tests within 24 hours of starting interim therapeutic anticoagulation.
Anticoagulation treatment for confirmed DVT or PE
1.3.5 Offer anticoagulation treatment for at least 3 months to people with confirmed proximal DVT or PE. For recommendations on treatment after 3 months see the section on long-term anticoagulation for secondary prevention.
1.3.6 If not already done, carry out baseline blood tests, as outlined in recommendation 1.3.4, when starting anticoagulation treatment.
1.3.7 When offering anticoagulation treatment, take into account comorbidities, contraindications and the person’s preferences.
Follow the recommendations on anticoagulation treatment in the sections on:
1.3.8 Offer either apixaban or rivaroxaban to people with confirmed proximal DVT or PE (but see recommendations 1.3.11 to 1.3.20 for people with any of the clinical features listed in recommendation 1.3.7). If neither apixaban nor rivaroxaban is suitable offer:
LMWH for at least 5 days followed by dabigatran or edoxaban or
LMWH concurrently with a vitamin K antagonist (VKA) for at least 5 days, or until the INR is at least 2.0 in 2 consecutive readings, followed by a VKA on its own.
1.3.9 Do not routinely offer unfractionated heparin (UFH) with a VKA to treat confirmed proximal DVT or PE unless the person has renal impairment or established renal failure (see recommendations 1.3.13 and 1.3.14) or an increased risk of bleeding.
For people with confirmed PE and haemodynamic instability, offer continuous UFH infusion and consider thrombolytic therapy (see the section on thrombolytic therapy).