CTEPH Identification an Standard Computerised Tomography Pulmonary Angiography in Pulmonary Embolism Patients

Study Overview
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Brief Summary
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In this study the investigators will evaluate whether more careful reading (than the current standard) of routine computerised tomography pulmonary angiography (CTPA) performed in the clinical work-up of suspected (pulmonary embolism (PE) will differentiate patients with acute PE from those with more chronic or acute on chronic PE, which could be indicative of the presence of chronic thromboembolic pulmonary hypertension (CTEPH)

Detailed Description
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The investigators will study 50 consecutive patients diagnosed with CTEPH as well as 50 patients diagnosed with acute PE in whom CTEPH was ruled out 2 years after the PE diagnosis by sequential echocardiography. The cases and controls will be matched based on the right-to-left ventrilcle diameter ratio. Three experienced thorax radiologists with specific expertise on acute PE and CTEPH will blindly assess the index CTPAs of the study population. In addition to the binominal judgement whether CTEPH signs are already present (or not), the presence of the following items will be scored by all 3 readers independently: Webs or bands Residual thrombus attached to the vascular wall Complete occlusion /retraction Mosaic perfusion Pulmonary infarct Parenchymal bands Bronchial arteries Right atrial (RA) dilatation Right ventricle (RV) dilatation Flattening of the septum Right ventricle (RV) hypertrophy Dilated truncus pulmonalis Cardiac signs of pulmonary hypertension (PH) Further remarks (free text)

Official Title
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Identification of CTEPH on Standard Computerised Tomography Pulmonary Angiography Performed in the Work-up of Suspected Pulmonary Embolism

Conditions
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CTEPH, Pulmonary Embolism, Early Diagnosis

Intervention / Treatment
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* Diagnostic Test: The initial CTPA will be reviewed


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients after an acute PE diagnosed with CTEPH according to current guidelines, patients after an acute PE in whom CTEPH is excluded by follow-up echocardiography availability of the CTPA scan of the initial PE episode Exclusion Criteria: CTEPH diagnosis based on other test results than a RHC Patients who did not receive anticoagulation after PE diagnosis Patients under the age of 18 years old Patients in the control group with a follow-up duration of less than 2 years after the index PE episode Use of a CTPA scanner with less than 32-detector rows

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| CTEPH patients<br>the initial CTPA scan will be reviewed in patients diagnosed with CTEPH after an episode of an acute PE | Diagnostic Test: The initial CTPA will be reviewed<br>* The initial CTPA will be reviewed<br>|
| non CTEPH patients<br>the initial CTPA scan will be reviewed in patients after an episode of an acute PE in whom CTEPH was excluded | Diagnostic Test: The initial CTPA will be reviewed<br>* The initial CTPA will be reviewed<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To Identify the Accuracy of Routine CTPA for the Distinction of CTEPH From Acute PE. | The sensitivity of CTPA is determined by calculating the proportion of scans that are read as positive for the CTEPH specific radiological pattern in patients with confirmed CTEPH and the specificity is determined by calculating the proportion of scans that are read as negative for the CTEPH specific radiological pattern in patients without CTEPH. | 1 year |