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NCT Number: NCT05735639

THRomboprophylaxis in Individuals Undergoing Superficial endoVEnous Treatment (THRIVE)

Endovenous interventions are keyhole operations for varicose veins that are carried out from within the vein itself. Varicose veins are enlarged veins close to the surface of the skin. They are connected to the bigger deeper veins in the leg (known as deep veins). Because of this, operations to close the varicose veins can increase the chance of a blood clot forming in the deep veins. Blood clots in the deep veins happen in around 1 in 50 people after endovenous operations. A clot in the leg can cause swelling, pain, and other long-term problems. If a clot in the leg breaks off and travels to the lungs, it can cause problems with the lung' ability to move oxygen from the air into the blood and may, in rare cases, be life threatening.

Varicose vein procedures may carry a slightly higher risk of blood clot formation, and we are currently unsure if current clot reducing medicines are beneficial in preventing blood clots in people having varicose vein procedures.

This study will investigate if it is worthwhile prescribing medicines to reduce blood clots after varicose vein procedures.

Recruiting

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Key information

Conditions

Venous Thromboembolism Cardiovascular Diseases Embolism and Thrombosis Thromboembolism Varicose Veins Vascular Diseases

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 4

Primary location

Imperial College Hospital NHS Foundation Trust

London, W6 8RF, United Kingdom

Location status: Recruiting

Location contact

Alun H Davies

CONTACT

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Adults (>18 years)
  • Scheduled to undergo endovenous intervention of truncal varicose veins under local anaesthesia
  • Treatment technologies including radiofrequency, laser, mechanochemical, foam sclerotherapy and cyanoacrylate glue

Exclusion criteria

  • Clinical indication for therapeutic anticoagulation e.g., atrial fibrillation
  • Previous personal or first-degree relative history of VTE
  • Thrombophilia
  • Female patients of childbearing potential who have a positive pregnancy test
  • A history of allergy to heparins or direct oral anticoagulants
  • A history of heparin-induced thrombocytopenia
  • Inherited and acquired bleeding disorders
  • Evidence of active bleeding
  • Concomitant major health problems such as active cancer and chronic renal and/or liver impairment
  • Known thrombocytopenia (platelets known to be less than 50 x 109

/l)

  • Surgery or major trauma in the previous 90 days
  • Recent ischemic stroke in the previous 90 days
  • Inability to provide consent

Treatment and study plan

Dalteparin Sodium

Drug

Low molecular weight heparin

Tinzaparin sodium

Drug

Low molecular weight heparin

Enoxaparin sodium

Drug

Low molecular weight heparin

Rivaroxaban

Drug

Direct oral anticoagulant

Apixaban

Drug

Direct oral anticoagulant

Dabigatran Etexilate

Drug

Direct oral anticoagulant

Primary outcomes

  1. Imaging confirmed lower limb deep vein thrombosis (DVT) with or without symptoms, or pulmonary embolism (PE) with symptoms within 90 days of varicose vein treatment.

    Time frame: 90 days

    The rate of lower limb DVT with or without symptoms, or PE with symptoms within 90 days of varicose vein treatment.

Secondary outcomes

  1. Lower limb DVT without symptoms

    Time frame: 21 - 28 days

    Duplex ultrasound scan

  2. Lower limb DVT with symptoms

    Time frame: 90 days

    Self-reported VTE outcome questionnaire

  3. PE with symptoms

    Time frame: 90 days

    VTE outcome questionnaire (self-reported) to determine the rate of PE

  4. Comparisons of quality of life at 7- and 90-days post-procedure

    Time frame: 90-days

    Using EQ-5D

  5. Cost-effectiveness of providing pharmacological thromboprophylaxis

    Time frame: 90 days

    Incremental Cost-Effectiveness Ratio (ICER)

  6. Exploratory analyses to assess how well a VTE risk assessment tool predicts VTE outcome

    Time frame: 90 days

    Venous thromboembolism risk as determined by the Department of Health Risk Assessment tool

  7. Exploratory analyses to assess how well a VTE risk assessment tool predicts VTE outcome

    Time frame: 90 days

    Venous thromboembolism risk as determined by the Caprini risk assessment model

  8. Mortality rates in each group

    Time frame: 90 days

    Rate of mortality

Study contacts

Contact information is provided by the study sponsor or research team.

Sarah Whittley

CONTACT

[email protected]

+442033117309

Sponsors and collaborators

Lead sponsor

Imperial College London

Other

Registry information

Official study title

THRomboprophylaxis in Individuals Undergoing Superficial endoVEnous Treatment (THRIVE) - a Multi-centre Assessor-blind Randomised-controlled Trial

Acronym: THRIVE

Important dates

Study start
2024
Primary completion
2027
Study completion
2027
First posted
Feb 21, 2023
Registry last updated
Jun 4, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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