A Study to Evaluate Direct Wire Pacing (DWP) for Measuring Fractional Flow Reserve (FFR)

Study Overview
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Brief Summary
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This is a randomized, non-inferiority, crossover investigation comparing the Direct Wire Pacing (DWP) versus standard method to measure Fractional Flow Reserve (FFR) in subjects with FFR indications. All subjects requiring on a clinical basis a pressure wire assessment of coronary artery stenosis(es) will be eligible to take part in the study.

Detailed Description
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Pressure wire-based Fractional Flow Reserve (FFR) has become the reference standard index of haemodynamic significance to guide revascularisation of intermediate coronary artery lesions. The FFR measurement determines the ratio of the maximum blood flow that can be achieved in a diseased or narrowed coronary artery to the maximum blood flow in a normal coronary artery. This ratio represents the potential decrease in distal coronary flow relative to coronary stenosis. FFR is easily measured during routine coronary angiography using a pressure wire to calculate the ratio of coronary pressure distal to a stenosis or diseased segment to aortic pressure under conditions of maximum myocardial hyperemia. An FFR of 1.0 is widely accepted as normal. An FFR of less than 0.80 is generally considered to be associated with coronary ischemia and widely accepted in favor of revascularization rather than conservative management. The current standard method of measuring FFR is to insert a pressure wire into the coronary artery while the hyperaemic agent, usually adenosine, is delivered by intracoronary bolus or continuous intravenous injection. Administration of adenosine may cause bradycardia and thus cause patient vagal discomfort. Direct Wire Pacing (DWP) can potentially overcome the drawbacks of the standard method when measuring FFR. Indeed, DWP allows to transmit an electrical current from the external pacemaker to the heart thanks to metallic FFR guidewire already used, and thus prevent bradycardia. In addition, there are some absolute contraindications to the use of Adenosine such as 2nd or 3rd degree atrioventricular block, untreated sinus dysfunction or long QT syndrome ...DWP could allow this highly recommended diagnostic tool (1A) to be used in this patient population. The investigators would therefore like to determine if the measurement of FFR by DWP would be non-inferior to the standard method to obtain precise FFR values and maximize patient's comfort.

Official Title
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A Randomized Crossover Study to Evaluate and Compare the Reproducibility and Tolerability of Direct Wire Pacing for Measuring Fractional Flow Reserve Versus Standard Method in Subjects With FFR Indications

Conditions
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Coronary Artery Stenosis, Fractional Flow Reserve

Intervention / Treatment
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* Diagnostic Test: FFR DWP
* Diagnostic Test: FFR


Participation Criteria
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Eligibility Criteria
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Eligible patient for coronary angiography. Inclusion Criteria: The patients included in the study must meet the following inclusion criteria : Patients ≥ 18 years old Patients with FFR indications Has given consent to undergo diagnostic coronary procedure Patients able to understand and provide informed consent Patients with Social Security coverage Prior to randomisation: Angiography demonstrates at least one coronary stenosis in an artery, requiring FFR measurement for physiological assessment. Exclusion Criteria: The patients included in the study should not meet the following inclusion criteria : Contraindications to use sensitivity to Adenosine or any of its excipients Technically inaccessible stenosis(es) Pregnant or breastfeeding woman Patients under judicial protection, tutorship or curatorship Patient participating in another interventional clinical trial

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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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: FFR followed by FFR-DWP (investigation)<br>The FFR measurement is performed with the standard method first followed by the FFR measurement with the DWP method. | Diagnostic Test: FFR DWP<br>* FFR will be measured twice in the same lesion : One with the standard method and the other with the DWP method.<br>Diagnostic Test: FFR<br>* FFR will be measured twice in the same lesion : One with the standard method and the other with the DWP method.<br>|
| Experimental: FFR-DWP (investigation) followed by FFR<br>The FFR measurement is performed with the DWP method first followed by the FFR measurement with the standard method. | Diagnostic Test: FFR DWP<br>* FFR will be measured twice in the same lesion : One with the standard method and the other with the DWP method.<br>Diagnostic Test: FFR<br>* FFR will be measured twice in the same lesion : One with the standard method and the other with the DWP method.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reproducibility of the FFR measurement | Evaluated by the number of patients with comparable FFR ratio recording. The FFR ratio should remain constant (+/-0.02) between the two modes of measuring FFR. | Intraoperative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of participants with Adverse Events | Assessed by the number of participants with adverse events during the procedure. | Intraoperative | 
| Tolerance | Assessed by asking patients during each FFR to grade verbally any symptoms of chest discomfort. | Intraoperative | 
| correlation between a disproportionately high FFR value and la presence of a (partially) infarcted territory | The correlation between a disproportionately high FFR value in presence of a (partially)infarcted territory will be assessed by the comparison the obtained FFR value, the degree of angiographic stenosis measured and the obtained stimulation threshold. | Intraoperative |