Assessment of Catheter-based Interrogation and Standard Techniques for Fractional Flow Reserve Measurement

Study Overview
=================
Brief Summary
-----------------
This study will assess the differences between Fractional Flow Reserve (FFR) measurements made by the Navvus catheter and a commercially available pressure guidewire in up to 240 subjects where FFR is clinically indicated. All subjects will receive diagnostic treatment according to clinical indications and center standard practice.

Detailed Description
-----------------
The ACIST-FFR study is a prospective, open label, observational, multi-center study designed to assess the differences, if any, between FFR measured by the Navvus catheter and a commercially available 0.014-inch pressure guidewire (St. Jude Medical, Volcano, hereafter referred to as the PW) in subjects with coronary artery disease (CAD) undergoing coronary angiography. This will be accomplished by comparing the FFR measurement obtained with the ACIST Medical Systems RXi System and Navvus catheter with the FFR measurement obtained by using a PW within the same subject across the same target lesion at the same time.

Official Title
-----------------
Assessment of Catheter-based Interrogation and Standard Techniques for Fractional Flow Reserve Measurement: the ACIST-FFR Study

Conditions
-----------------
Coronary Artery Disease

Intervention / Treatment
-----------------
* Device: RXi System
* Device: Pressure Wire


Participation Criteria
=================
Eligibility Criteria
-----------------
General Inclusion Criteria: Subject is 18 years of age or older Subject has a clinical indication for coronary angiography Subject or subject's legal representative has the ability to understand and provide signed consent for participating in the study Angiographic Inclusion Criteria: Vessel has a TIMI flow = 3 Subject has de novo lesion which physician has determined has a clinical indication for FFR measurement RVD of the target lesion is assessed by the operator to be ≥2.25 mm. General Exclusion Criteria: Subjects with acute ST-elevation or non-ST-elevation myocardial infarction as the indication for coronary angiography NYHA Class 4 severe heart failure Angiographic Exclusion Criteria: Target vessel has angiographically visible or suspected thrombus. Target lesion is within a bypass graft. Angiographic evidence of a dissection prior to initiation of PW measurements. Target vessel contains excessive tortuosity or calcification.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Participants<br>Subjects who satisfy both general and angiographic inclusion/exclusion criteria, and who have the pressure measurement taken with the Navvus catheter. | Device: RXi System<br>* Provide hemodynamic information for the diagnosis and treatment of coronary and peripheral artery disease. The system is intended for use in catheterization and related cardiovascular specialty laboratories to compute and display fractional flow reserve or FFR. Measurement of FFR requires simultaneously monitoring the blood pressures proximal and distal to a lesion. The RXi system includes a single use catheter (Navvus) with a pressure sensor for acquisition of the distal pressure. The proximal pressure is acquired by the guide catheter via an interface to the hospital hemodynamic monitor. The Navvus catheter interfaces to the RXi system console which includes embedded software, a user interface touch screen and associated electronics.<br>* Other names: Navvus Catheter;Device: Pressure Wire<br>* Provide hemodynamic information for the diagnosis and treatment of coronary and peripheral artery disease. The system is intended for use in catheterization and related cardiovascular specialty laboratories to compute and display fractional flow reserve or FFR.<br>* Other names: Volcano PrimeWire Prestige;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| FFR Measurements | Bias between Navvus and PW FFR measurements, as assessed by Bland-Altman analysis | Duration of FFR Procedure | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Slope of Passing-Bablok | Slope of Passing-Bablok fit between paired FFR measurements by Navvus and PW | Duration of FFR Procedure | 
| Intercept of Passing-Bablok | Intercept of Passing-Bablok fit between paired FFR measurements by Navvus and PW | Duration of FFR Procedure | 
| Comparability of FFR Measurements | Comparability of PW FFR and Navvus FFR measurements at PW FFR=0.80, by Passing-Bablok analysis. | Duration of FFR Procedure | 
| Diagnostic FFR concurrence of stenosis significance | Concurrence of Navvus FFR diagnostic accuracy of stenosis significance, using PW FFR ≤0.80 as the standard. | Duration of FFR Procedure | 
| Device success rate | Device success rate, defined as a valid FFR reading, for each system individually, and comparison between the two systems. | Duration of FFR Procedure | 
| Mean drift | Mean drift, defined as the absolute difference between Pd/Pa at the equalization position after pullback and 1.00, for each system individually, and comparison between the two systems. | Duration of FFR Procedure | 
| Rate of clinically significant drift | Rate of clinically significant drift, defined as drift >0.03, for each system individually, and comparison between the two systems. | Duration of FFR Procedure | 
| Rate of device-related adverse effects | Rate of device-related adverse effects, for each system individually, and comparison between the two systems. | Duration of FFR Procedure | 
| PW FFR measurements with Navvus across and not across lesion | Comparisons between PW FFR measurements with Navvus across lesion and with Navvus not across lesion, including bias as assessed by Bland-Altman analysis. | Duration of FFR Procedure | 
| Comparison of FFR Measurements including bias | Comparisons between PW (with Navvus present in lesion) and Navvus FFR measurements, including bias assessed by Bland-Altman analysis. | Duration of FFR Procedure | 
| Correlation between Navvus diagnostic accuracy, bias, and angiographic characteristics | Relationship between Navvus diagnostic accuracy, bias, and angiographic characteristics such as lesion length and reference vessel diameter. | Duration of FFR Procedure | 
| PW Pd/Pa diagnostic concurrence of stenosis signficance | PW Pd/Pa diagnostic accuracy (concurrence) of stenosis significance, using PW FFR ≤0.80 as the standard. | Duration of FFR Procedure | 
| PW Pd/Pa measurements with Navvus across and not across lesion | Comparisons between PW Pd/Pa measurements with Navvus across lesion and with Navvus not across lesion, including bias as assessed by Bland-Altman analysis. | Duration of FFR Procedure | 
| Comparison of Pd/Pa Measurements including bias | Comparisons between PW (with Navvus present in lesion) and Navvus Pd/Pa measurements, including bias assessed by Bland-Altman analysis. | Duration of FFR Procedure | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Fractional Flow Reserve, Rapid Exchange, Catheter