Aortic Dissection Detection Risk Score Plus D-dimer in Suspected Acute Aortic Dissection

Study Overview
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Brief Summary
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Acute aortic dissection (AD) is a deadly, difficult to diagnose disease presenting with an array of common and unspecific symptoms. Aortic dissection detection (ADD) risk score is a bedside clinical tool to estimate the risk of AD. D-dimer has been evaluated in several studies as a biomarker of AD and has showed a pooled diagnostic sensitivity of 97%. However, considering the severe morbidity and mortality of AD, a negative d-dimer per se is considered insufficient to rule-out AD in unselected patients. The aim of the present study is to evaluate whether the diagnostic performance of d-dimer differs in patients at different clinical risk of AD, and in particular whether a negative d-dimer test may allow safe rule-out of AD in any patient subgroup without necessity to perform urgent aortic imaging. Consecutive adult patients with suspected AD presenting to Emergency Department will be enrolled before the establishment of a final diagnosis; a standardized clinical form comprehensive of presence/absence of 12 risk markers allowing ADD risk score fulfilled and d-dimer levels measured at presentation. The aortic imaging exam used to confirm or refuse of AD will be computed tomography angiography or transesophageal echocardiography and final diagnosis established after reviewing of all available data. The accuracy, failure rate and efficiency of a diagnostic strategy combining standardized clinical stratification via the ADD risk score with d-dimer testing will therefore be assessed.

Detailed Description
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Acute AD will include the following etiological entities, also known as acute aortic syndromes: acute aortic dissection, intramural aortic hematoma, penetrating aortic ulcer and spontaneous aortic rupture. A pre-specified secondary sub-analysis will evaluate the diagnostic accuracy of focus cardiac ultrasound (FoCUS) and chest x ray for suspected AD.

Official Title
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Aortic Dissection Detection Risk Score Plus D-dimer in the Diagnostic Workup of Suspected Acute Aortic Dissection: a Prospective Multicenter Study

Conditions
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Aortic Dissection

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age >18 years Presentation to the ED with any of the following symptoms: chest pain, back pain, abdominal pain, syncope or symptoms of perfusion deficit (central nervous system, mesenteric, myocardial, or limb ischemia) Aortic dissection considered among the differential diagnosis by the attending physician. Enrollment in the study will be decided by the attending physician during evaluation in the ED and before the establishment of a final diagnosis. Exclusion Criteria: An alternative diagnosis to AD objectively established by the attending physician after the initial medical evaluation Clinical severity or other conditions not allowing complete evaluation/proper enrollment Lack of consent to participate to the study

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Suspected AD<br>Consecutive adult patients with suspected AD presenting to Emergency Departments will be enrolled at the time of initial medical evaluation and before the establishment of a final diagnosis. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Accuracy of ADD risk score and d-dimer in suspected aortic dissection | The diagnostic performance of d-dimer will be assessed by computing sensitivity, specificity, negative and positive predictive values and negative and positive likelihood ratios with their 95% confident interval (95% CI) in all patients and within ADD risk score classes. The ADD risk score will be calculated based on the number of categories where at least one risk marker is present. Patients will be divided in low-risk (0 risk markers, ADD risk score 0), intermediate-risk (ADD risk score 1, at least 1 risk marker in 1 ADD risk category) and high-risk (ADD risk >1, at least 1 risk marker in >1 ADD risk categories). For diagnostic accuracy analyses, also a category of non-high-risk patients (ADD risk score ≤1) will be used. | 2 weeks after the end of recruitment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Efficiency and failure rate of a diagnostic strategy using ADD risk score and d-dimer | Conventional accuracy measures, failure rate and the efficiency of d-dimer will be calculated in high-risk patients (ADD risk score >1), in low-risk patients (ADD risk score 0) and in the intermediate and low-risk patients combined (non high-risk patients, ADD risk score ≤1). Failure rate (false negative proportion) will be calculated as the number of patients with a negative d-dimer and a final diagnosis of AD divided by all patients with negative d-dimer in the same risk group. The efficiency of the diagnostic strategy will be calculated as the number of patients with a negative d-dimer within a risk group divided by all included patients. | 2 weeks after the end of recruitment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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aortic dissection, diagnosis, emergency medicine, d-dimer