Safely Ruling Out Deep Vein Thrombosis in Pregnancy With the LEFt Clinical Decision Rule and D-Dimer (LEaD)
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|ClinicalTrials.gov Identifier: NCT02507180|
Recruitment Status : Recruiting
First Posted : July 23, 2015
Last Update Posted : February 27, 2020
|Condition or disease||Intervention/treatment|
|Pregnancy Deep Vein Thrombosis||Other: LEFt clinical decision rule|
VTE is a leading cause of maternal death in the developed world. Suspected DVT in pregnancy is a common clinical problem faced by clinicians daily. The only validated method to exclude DVT in pregnancy requires leg vein CUS imaging. This imaging modality is costly and has limited availability (only available in radiology departments and, usually, only during weekday daytime hours) often necessitating referral to the emergency room for initiation of heparin injections until leg vein CUS can be obtained. A simple and seemingly powerful clinical decision rule (LEFt) and a simple blood test (D-dimer) may be promising to exclude DVT in pregnancy without the need for diagnostic imaging. Validating the safety of a simple, non-invasive, widely available approach to suspected DVT in pregnancy would be an important advance in maternal health.
A prospective cohort diagnostic management study in pregnant women with suspected DVT, with three-month follow-up for symptomatic VTE will take place in multiple centres throughout Canada and Europe.
After obtaining informed consent, all patient will have the LEFt clinical decision rule applied by the attending physician and will have D-Dimer testing (D-Dimer results of test performed within 24 hours will be accepted and do not need to be repeated).
Patients with an "unlikely" LEFt score of 0 or 1 point and a negative D-dimer will not undergo diagnostic imaging.
Patients with either a "likely" LEFt score of 2 or 3 points or a positive D-dimer will undergo either a single complete leg vein compression ultrasound (CCUS) (Day 1) or a serial proximal leg vein (CUS) (Day 1 and Day 7).
All patients will be followed for 3 months for symptomatic VTE.
|Study Type :||Observational|
|Estimated Enrollment :||366 participants|
|Official Title:||Safely Ruling Out Deep Vein Thrombosis in Pregnancy With the LEFt Clinical Decision Rule and D-Dimer: the LEaD Study. A Prospective Cohort Study.|
|Actual Study Start Date :||September 2015|
|Estimated Primary Completion Date :||September 2021|
|Estimated Study Completion Date :||January 2022|
Pregnant women with suspected DVT
Pregnant women presenting with suspected DVT will have the LEFt clinical decision rule applied by the attending physician and will have a clinical D-dimer test done.
Other: LEFt clinical decision rule
The LEFt rule
Predictor Points Left leg symptoms +1 Extremity swelling (≥ 2 cm difference in calf circumference +1 First trimester symptom onset +1
Clinical probability Unlikely: 0 or 1 point Likely: > 1 point
- Number of VTE diagnosed in patients deemed DVT "unlikely" [ Time Frame: 3 months after presentation ]The primary outcome will be the number of VTE (distal or proximal DVT, sub-segmental or greater pulmonary embolism (PE), death attributable to VTE) documented during the three-month follow-up in those patients left untreated for DVT on the basis of the study's initial diagnostic management (see Figure 2) i.e. not doing CUS on patients with an "unlikely" LEFt score (0 or 1 points) and a negative D-dimer
- Number of VTE diagnosed in all patients [ Time Frame: 3 months after presentation ]The number of major VTE events (any proximal DVT, segmental or greater PE, death attributable to VTE) documented during the 3-month follow-up in all patients. Some clinicians may not treat distal DVT or sub-segmental PE in pregnancy, instead following these patients with serial US imaging, and hence may prefer to focus on this outcome that excludes distal DVT and sub-segmental PE.
- Proportion of women requiring CUS [ Time Frame: Baseline ]The proportion of women requiring CUS using the study's diagnostic strategy (i.e. no imaging in patients with an "unlikely" LEFt score (0 or 1 points) and a negative D-dimer). We anticipate that an important proportion (>40%) of women will be able to avoid the need for CUS imaging based on safely excluding DVT on the basis of an "unlikely" LEFt (0 or 1) and a negative D-dimer. However, if this proportion is very low (<5%) this may argue against the widespread adoption of our proposed diagnostic management strategy even if it proves to be safe.
- Average number of CUS in pregnant women with suspected DVT [ Time Frame: 7 days from initial presentation ]The mean number of ultrasounds per patient with suspected DVT. In the study by Chan, validating serial CUS in pregnancy, the mean number of US per patient was 2.8630. We anticipate that we will be able to reduce this by >40% with our diagnostic approach.
Biospecimen Retention: Samples Without DNA
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02507180
|Contact: Marc A Rodger, MDfirstname.lastname@example.org|
|Contact: Veronica Bates, BSc||613-737-8899 ext email@example.com|
|United States, Utah|
|Intermountain Healthcare, Inc.||Not yet recruiting|
|Murray, Utah, United States|
|Contact: Scott Stevens, MD|
|Principal Investigator: Scott Stevens, MD|
|Foothills Medical Centre||Recruiting|
|Calgary, Alberta, Canada|
|Contact: Jessica Lee, BA|
|Contact: Alissa Kazakoff, BSc|
|Principal Investigator: Paul Gibson, MD|
|Royal Alexandra Hospital||Recruiting|
|Edmonton, Alberta, Canada|
|Contact: Shauna Littlefair, RN|
|Principal Investigator: Rshmi Khurana, MD|
|Canada, British Columbia|
|Children's and Women's Health Centre of British Columbia||Recruiting|
|Vancouver, British Columbia, Canada|
|Contact: Frannie MacKenzie|
|Principal Investigator: Wee-Shian Chan, MD|
|Canada, Nova Scotia|
|Queen Elizabeth II Health Science Centre||Recruiting|
|Halifax, Nova Scotia, Canada|
|Contact: Blaine Gallant, RN|
|Principal Investigator: Sudeep Shivakumar, MD|
|Hamilton Health Sciences Centre||Recruiting|
|Hamilton, Ontario, Canada|
|Contact: Carolyn Webb, RN|
|Principal Investigator: Shannon Bates, MD|
|London Health Sciences Centre||Withdrawn|
|London, Ontario, Canada|
|Ottawa Hospital Research Institute||Recruiting|
|Ottawa, Ontario, Canada|
|Contact: Veronica Whitham, BSc|
|Principal Investigator: Marc Rodger, MD|
|Sunnybrook Medical Hospital||Withdrawn|
|Toronto, Ontario, Canada|
|Jewish General Hospital||Recruiting|
|Montreal, Quebec, Canada|
|Contact: Carla Strulovitch, RN|
|Principal Investigator: Susam Kahn, MD|
|Leiden University Medical Center||Recruiting|
|Contact: Erik Klok, MD|
|Principal Investigator: Erik Klok, MD|
|Hopitaux Universitaires de Geneve||Recruiting|
|Contact: Louise Riberdy, MD|
|Principal Investigator: Marc Righini, MD|
|Principal Investigator:||Marc Rodger, MD||Ottawa Hospital Research Institute|
|Principal Investigator:||Marc Righini, MD||Hopitaux Universitaires de Geneve|