Diagnostic Agreement of iFR and QFR.

Study Overview
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Brief Summary
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A Prospective, observational, single center diagnostic study to investigate the the diagnostic agreement between QFR and the pressure wire-based iFR in a real world setting.

Detailed Description
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During coronary angiography, intermediate stenoses can not be adequately assessed by visual assessment alone. It is necessary to evaluate the functional significance to guide their treatment. Fractional Flow Reserve (FFR) is the current gold standard for determining this functional significance but its adoption in clinical practice remains low. The instantaneous wave-free ratio (iFR) is an alternative way to determine the flow-limiting characteristics of a coronary stenosis with a pressure wire but without the need to induce hyperemia. Large randomised trials have confirmed the non-inferiority of iFR in respect to FFR in terms of outcome. Quantitative Flow Ratio (QFR) is another new method for evaluating the functional significance of coronary stenosis It is a software-based analysis of conventional angiographic images to estimate the pressure drop caused by a coronary stenosis. The diagnostic agreement with FFR seemed promising in the FAVOR Pilot Study and a larger trial is enrolling for confirmation. A stepwise approach of QFR and iFR could make the functional assessment of intermediate stenoses more practical and cost-effective. However before being used as a combination in daily practice, QFR has to be validated in respect to iFR. The primary objective of the trial is to investigate the diagnostic agreement between QFR and the pressure wire-based iFR in a real world setting

Official Title
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DETErmining the funCTional Significance of Intermediate Stenoses in isCHEMIc heArt Disease (DETECT ISCHEMIA): Diagnostic Agreement of iFR and QFR.

Conditions
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Fractional Flow Reserve, Myocardial, Coronary Artery Disease

Intervention / Treatment
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* Diagnostic Test: QFR and iFR


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age > 18 with symptoms of myocardial ischemia and angina or angina equivalent (chest pain, abnormal stress testing, abnormal noninvasive testing) Patients witch semi recent (>3 days) acute coronary syndromes can be included but only for the non-culprit vessels and outside of primary intervention during acute myocardial infarction. Willing to participate and able to understand, read and sign the informed consent document before the planned procedure Eligible for coronary angiography and/or percutaneous coronary intervention Coronary artery disease with at least 1 or more visually assessed de novo coronary stenosis (30-90% diameter stenosis) in native major epicardial vessel or its branches by coronary angiogram. Exclusion criteria: Contraindication to adenosine administration Previous Coronary Artery Bypass surgery with patent grafts to the interrogated vessel

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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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| FFR-iFR-QFR group<br> | Diagnostic Test: QFR and iFR<br>* iFR® (CE-Marked) is a pressure-derived, hyperemia-free index for the assessment of coronary stenosis relevance. This option consists of an FFR-iFR® specific patient interface module (PIM-FFR) which can be connected to the Volcano system - VOLCANO s5 or s5i™ platform equipped with iFR® option. QFR® (CE-Marked) is an angio-based FFR estimation using the analytical Software QAngio XA 3D from Medis medical imaging B.V., The Netherland<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Diagnostic performance of QFR in comparison to iFR | reported as sensitivity, specificity, positive and negative likelihood ratio of QFR according to iFR | 1 hour | 
| QFR- iFR diagnostic grey zone calculation. | QFR limits for achieving 95% sensitivity and specificity in comparison to iFR | 1 hour | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Diagnostic performance of QFR in comparison to FFR | reported as sensitivity, specificity, positive and negative likelihood ratio of QFR according to FFR | 1 hour | 
| QFR- FFR diagnostic grey zone calculation. | QFR limits for achieving 95% sensitivity and specificity in comparison to FFR | 1 hour | 
| Diagnostic performance of iFR in comparison to FFR | reported as sensitivity, specificity, positive and negative likelihood ratio of iFR according to FFR | 1 hour | 
| iFR- FFR diagnostic grey zone calculation. | iFR limits for achieving 95% sensitivity and specificity in comparison to FFR | 1 hour | 
| effect of 3D QCA characteristics on QFR-iFR-FFR disagreement. | Influence of minimum luminal area (MLA), percentage area stenosis, lesion length, and minimum luminal diameter (MLD) and percentage diameter stenosis in the prediction of QFR-iFR-FFR disagreement. | 1 hour | 
| Effect of lesion location on QFR-iFR-FFR disagreement. | Evaluation of lesion location in the prediction of QFR-iFR-FFR disagreement. | 1 hour | 
| Effect of p20-DAC2 score in proximal and mid-LAD stenosis on QFR-iFR-FFR disagreement. | Evaluation of p20-DAC2 score in proximal and mid-LAD stenosis in in the prediction of QFR-iFR-FFR disagreement. | 1 hour | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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instantaneous Flow Ratio, Quantitative Flow Ratio, Fractional Flow Reserve