The OPTICA Study - The Optimised Computed Tomography Pulmonary Angiography (CTPA) in Pregnancy, Quality and Safety Study

Study Overview
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Brief Summary
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A prospective multicentre study aiming to validate the clinical utility and safety of an optimised low-dose computed-tomography pulmonary angiogram (CTPA) protocol for suspected pulmonary embolism in pregnancy

Detailed Description
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The OPTICA study is the first prospective study of a low-dose CTPA protocol for the pregnant population. It will define the achievable dose, image quality and safety of this protocol and provide an evidence base upon which modern CTPA protocols can be appropriately compared to scintigraphy for this population. Pregnant women undergoing the specified low-dose CTPA protocol for suspected pulmonary embolism (PE), agreed across study sites with equivalent computed-tomography (CT) capabilities, will be included. Independent review of CTPAs by two radiology consultants, image data analysis and 3-month patient follow up will be performed. The diagnostic algorithm employs chest-x-ray and lower limb Doppler if lower limb symptoms are present, followed by CTPA in cases where advanced imaging is required. D-dimer is permitted within the diagnostic algorithm for patients recruited after implementation of the updated 2019 European Society of Cardiology guidelines for diagnosis and management of acute pulmonary embolism.

Official Title
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The OPTICA Study - A Prospective Study Assessing the Quality and Safety of an Optimised CTPA Protocol in Pregnancy

Conditions
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Pulmonary Embolism, Pregnancy Related, Venous Thromboembolism

Intervention / Treatment
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* Diagnostic Test: OPTICA CTPA Protocol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Pregnant patients with a suspected pulmonary embolism Age≥18 years Exclusion Criteria: Age < 18 years Ultrasound proof of symptomatic proximal deep vein thrombosis Contraindication to helical CT because of allergy to intravenous iodinated contrast or renal insufficiency (creatinine clearance <30 ml/min) Treatment with full-dose therapeutic low molecular weight heparin or unfractionated heparin initiated 24 h or more prior to eligibility assessment Treatment with vitamin K antagonists (coumarin derivates i.e. warfarin) Unable or unwilling to consent Unable to part-take in follow-up Life expectancy <3 months

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Pregnant Patients with Suspected PE<br>Pregnant Patients with Suspected pulmonary embolism undergoing low dose CT pulmonary angiogram | Diagnostic Test: OPTICA CTPA Protocol<br>* Low dose CT pulmonary angiogram protocol<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of Venous Thrombo-Embolism (VTE) | 3-month incidence of venous thromboembolism in pregnant patients in whom pulmonary embolism was excluded at baseline CT pulmonary angiogram. | 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maternal Effective Dose | Maternal Effective Dose | 3 months | 
| Breast Radiation Dose | Breast Dose | 3 months | 
| Foetal Radiation Dose | Foetal (Uterine) Dose | 3 months | 
| Signal to Noise Ratio | Image Quality - Objective Variable | 3 months | 
| Contrast to Noise Ratio | Image Quality - Objective Variable | 3 months | 
| Mean Pulmonary Trunk Enhancement | Image Quality - Objective Variable (Hounsfield Units) | 3 months | 
| Subjective Imaging Quality Grade | Subjective Imaging Quality Score: Score 1 - 5. Lowest score of 1 indicates a non diagnostic quality study. Best score of 5 indicates excellent quality / excellent opacification to the segmental pulmonary vessel level. | 3 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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pulmonary embolism, pregnancy, tomography xray computed, radiation dosage, negative predictive value