Computed Tomography CT Venography During Postpartum Venous Thromboembolism

Study Overview
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Brief Summary
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The purpose of this study is to determine whether systematically performing computed tomography (CT) venography (i.e a CT acquisition of the pelvis and of the lower limbs, during the venous phase of opacification) in addition to thoracic CT angiography in women with suspected postpartum pulmonary embolism (PE) results in a gain in venous thromboembolism detection rate.

Detailed Description
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Pulmonary embolism (PE) remains a leading cause of maternal death during postpartum in developed countries; Thoracic computed tomography angiography (CTA) is the first-line diagnostic test for PE suspicion, but has a 20 to 35% rate of inconclusiveness during pregnancy and postpartum, 2 to 3 times higher than that of the general population. CT venography (CTV) consists in a delayed CT acquisition of the abdomen, pelvis and lower limbs, 3 minutes after starting contrast administration. It can be used for detecting deep venous thrombosis (DVT), the source of emboli in most PEs. The investigators hypothesized most postpartum PEs are due to pelvic vein thrombosis and that detecting such pelvic DVT by performing systematic CTV could increase the overall venous thromboembolism (VTE) detection.

Official Title
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Contribution of CT Venography for Diagnosing Venous Thromboembolism During Postpartum

Conditions
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Pulmonary Thromboembolism

Intervention / Treatment
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* Procedure: computed tomography venography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Women with clinically suspected pulmonary embolism (PE) during the first 6 weeks postpartum, without any sign of severe PE (shock, hypotension), referred for CT angiography Absence of contraindication to iodinated contrast medium injection (Previous allergic reaction to iodinated contrast medium, renal insufficiency with creatine clearance less than 30mL/mn, uncontrolled hyperthyroidism) Age > 18 years Health insurance Possibility to have 3-month follow-up Obtention of written informed consent (ability to give consent) Exclusion Criteria: Anticoagulation at therapeutic dosage for another reason than the suspicion of PE for more than 72 hours New pregnancy (In case of any doubt after medical history review, βHCG blood test must be realized to ensure patient's pregnancy status) Contrast medium extravasation during injection CTA or CTV not performed according to the study requirements

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Cohort<br>computed tomography venography | Procedure: computed tomography venography<br>* systematically performing computed tomography venography in addition to thoracic computed tomography angiography<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of detected venous thromboembolism (VTE) based on Computed Tomography Angiography (CTA) plus Computed Tomography Venography (CTV) | VTE detection rate for readings based on CTA plus CTV as compared to readings based on CTA alone | one day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Radiation doses due to CT venography |  | 3 months | 
| kappa coefficients assessing inter-readers agreement for CT venography readings |  | 3 months |