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Pd/Pa vs iFR™ in an Unselected Population Referred for Invasive Angiography (VERIFY2)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT02377310
Recruitment Status : Completed
First Posted : March 3, 2015
Last Update Posted : August 13, 2015
Information provided by (Responsible Party):
Golden Jubilee National Hospital

Brief Summary:

Instantaneous wave-free ratio (iFR™) is a novel non-hyperaemic index of the functional significance of a coronary stenosis. Previous studies have shown variable levels of correlation with the established hyperaemic index FFR. In addition it has been proposed that iFR™ has superior diagnostic accuracy when compared to mean whole cardiac cycle Pd/Pa which can also be used to predict FFR.

We plan to undertake a prospective clinical study in consecutive patients already undergoing FFR assessment in the cardiac catheterisation laboratory to compare the ability of iFR™ and Pd/Pa (both measured using the proprietary Volcano system) to predict FFR. We will explore the level of misclassification of flow limiting disease that results from use of iFR™ and resting Pd/Pa employed using either binary cut-off algorithms or in a hybrid decision making protocol. We plan to analyse 260 vessels over a 18 month period. Hyperaemia will be induced by intravenous adenosine (140 ug/kg/min) administered wherever possible via an antecubital vein. Intra-coronary nitrates will also be given in line with the standard care procedure for FFR measurement. Final clinical decisions following coronary physiology will be based on steady state FFR.

Condition or disease
Coronary Artery Disease Plaque Atherosclerosis Fractional Flow Reserve

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Study Type : Observational
Actual Enrollment : 197 participants
Observational Model: Cohort
Time Perspective: Prospective
Official Title: A Comparative Study of Resting Coronary Pressure Gradient, Instantaneous Wave-free Ratio and Fractional Flow Reserve in an Unselected Population Referred for Invasive Angiography: The VERIFY 2 Study
Study Start Date : September 2013
Actual Primary Completion Date : April 2015
Actual Study Completion Date : April 2015

All patients
All patients will undergo coronary physiological study with measurement of resting Pd/Pa, iFR™, hyperaemic iFR and FFR.

Primary Outcome Measures :
  1. To determine the diagnostic accuracy of instantaneous wave-free ratio (binary cut-off value 0.90) versus resting Pd/Pa (binary cut-off value 0.92) in reference to FFR. [ Time Frame: 30 days ]
    Resting Pd/Pa will be compared to iFR™ in reference to FFR.

Secondary Outcome Measures :
  1. To determine the diagnostic accuracy of hybrid iFR™/FFR versus hybrid resting Pd/Pa/FFR in reference to FFR [ Time Frame: 30 days ]
    Adenosine zone for iFR is 0.86-0.93, Adenosine zone for resting Pd/Pa is 0.87-0.94.

  2. To compare steady state FFR to minimum FFR [ Time Frame: 30 days ]
    FFR recorded by the operator as the minimum value will be compared with the steady state value and the impact on vessel classification will be assessed

  3. To investigate the influence of hyperemia on iFR™. [ Time Frame: 30 days ]
    iFR™ will be reassessed after administration of adenosine to evaluate whether this increases agreement with FFR.

  4. To assess the rate of revascularization per (1) artery and (2) per patient, associated with iFR™-guided management vs. FFR-guided management. [ Time Frame: 30 days ]
    An analysis of the total number of vessels and patients that would potentially undergo revascularisation will be used to compare iFR™ versus FFR guided managment.

  5. To assess serious adverse events in patients receiving intravenous adenosine [ Time Frame: 30 days ]
    Patients will be monitored during coronary physiology studies to assess the safety of intravenous adenosine infusion with assessment of side effects leading to early termination of the infusion.

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
All consecutive patients undergoing FFR assessment for standard clinical indications.

Inclusion Criteria:

All patients ≥18 years of age, already undergoing pressure wire assessment and able to consent

Exclusion Criteria:

Inability to receive adenosine

Extremely tortuous vessels

Highly calcified lesions unsuitable for pressure wire assessment

coronary artery occlusion

acute MI within 3 days

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT02377310

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United Kingdom
Golden Jubilee National Hospital
Glasgow, Dunbartonshire, United Kingdom, G81 4DY
Sponsors and Collaborators
Golden Jubilee National Hospital
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Study Director: Keith G Oldroyd, M.D. Golden Jubilee National Hospital
Publications automatically indexed to this study by Identifier (NCT Number):
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Responsible Party: Golden Jubilee National Hospital Identifier: NCT02377310    
Other Study ID Numbers: 1.0
First Posted: March 3, 2015    Key Record Dates
Last Update Posted: August 13, 2015
Last Verified: August 2015
Additional relevant MeSH terms:
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Coronary Artery Disease
Coronary Disease
Myocardial Ischemia
Heart Diseases
Cardiovascular Diseases
Arterial Occlusive Diseases
Vascular Diseases