Determination of Fractional Flow Reserve by Anatomic Computed Tomographic Angiography

Not Applicable

Completed

Brief Summary: This is a prospective, multi-center trial conducted at up to 20 US, Canadian, European and Asian centers designed to determine the diagnostic performance of CT-FLOW (the investigational technology) by coronary computed tomographic angiography (CCTA) for non-invasive assessment of the hemodynamic significance of coronary lesions, as compared to direct measurement of fractional flow reserve (FFR) during cardiac catheterization as a reference standard.

Detailed Description: 285 patient, prospective, multi-center trial conducted at up to 20 US, Canadian, European and Asian centers designed to determine the diagnostic performance of CT-FLOW (the investigational technology) by coronary computed tomographic angiography (CCTA) for non-invasive assessment of the hemodynamic significance of coronary lesions, as compared to direct measurement of fractional flow reserve (FFR) during cardiac catheterization as a reference standard

Recruitment & Eligibility

Inclusion Criteria

Age >18 years
Patients providing written informed consent
Scheduled to undergo clinically-indicated non-emergent invasive coronary angiography (ICA)
Has undergone >64 multidetector row CCTA within 60 days prior to ICA
No cardiac interventional therapy between the CCTA and ICA

Exclusion Criteria

Prior coronary artery bypass graft (CABG) surgery
Prior percutaneous coronary intervention (PCI) for which suspected coronary artery lesion(s) are within a stented coronary vessel
Contraindication to adenosine, including 2nd or 3rd degree heart block; sick sinus syndrome; long QT syndrome; severe hypotension, severe asthma, , severe COPD or bronchodilator-dependent COPD
Suspicion of acute coronary syndrome (acute myocardial infarction and unstable angina)
Recent prior myocardial infarction within 40 days of ICA
Known complex congenital heart disease
Prior pacemaker or internal defibrillator lead implantation
Prosthetic heart valve
Significant arrhythmia or tachycardia
Impaired chronic renal function (serum creatinine >1.5 mg/dl
Patients with known anaphylactic allergy to iodinated contrast
Pregnancy or unknown pregnancy status
Body mass index >35
Patient requires an emergent procedure
Evidence of ongoing or active clinical instability, including acute chest pain (sudden onset), cardiogenic shock, unstable blood pressure with systolic blood pressure <90 mmHg, and severe congestive heart failure (NYHA III or IV) or acute pulmonary edema
Any active, serious, life-threatening disease with a life expectancy of less than 2 months
Inability to comply with study procedures

Arm && Interventions

Group	Intervention	Description
Single arm study	FFR	Patients will receive cCTA, ICA, FFR, and cFFR per protocol.

Primary Outcome Measures

Name	Time	Method
Percentage of Participants With Diagnostic Accuracy of CCTA Plus FFRCT and CCTA Alone	1 day	Diagnostic accuracy of CCTA (Cardiac Computed Tomography Angiography) plus FFRCT (Noninvasive Fractional Flow Reserve computed from CCTA) to determine presence or absence of at least one hemodynamically (HD)-significant coronary artery stenosis\* at the subject level using binary outcomes when compared to invasive FFR (Fractional Flow Reserve) as the reference standard. In the per-patient analysis, vessels with the most adverse clinical status were selected to represent a given patient. FFR and FFRCT measurements were recorded on a continuous scale and dichotomized at the 0.80 threshold (values ≤0.80 considered diseased; values \>0.80 nondiagnostic for ischemia). Stenosis on CCTA was recorded at the 50% threshold (stenoses ≥50% considered obstructive and \<50% as non-significant). Prespecified primary endpoint was expected to be greater than 70% of the lower bound of the 95% confidence interval.

Secondary Outcome Measures

Name	Time	Method
Diagnostic Performance of CCTA Plus FFRCT at the Subject Level	1 day	Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of CCTA plus CT-FLOW at the subject level using binary outcomes when compared to FFR as the reference standard.