HeartFlowNXT - HeartFlow Analysis of Coronary Blood Flow Using Coronary CT Angiography (HFNXT)

This study has been completed.
Sponsor:
Collaborator:
Case Western Reserve University
Information provided by (Responsible Party):
HeartFlow, Inc.
ClinicalTrials.gov Identifier:
NCT01757678
First received: December 18, 2012
Last updated: September 10, 2013
Last verified: September 2013
  Purpose

To determine the diagnostic performance of FFRCT by coronary computed tomographic angiography (cCTA), as compared to cCTA alone, for non-invasive determination of the presence of a hemodynamically significant coronary lesion, using direct measurement of fractional flow reserve (FFR) during cardiac catheterization as a reference standard.


Condition Intervention Phase
The Targeted Population is Subjects With Suspected CAD Who Are Referred for Non-emergent Clinically-indicated Invasive Coronary Angiography.
Device: Measured FFR
Phase 4

Study Type: Interventional
Study Design: Endpoint Classification: Efficacy Study
Intervention Model: Single Group Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Diagnostic
Official Title: HeartFlowNXT - HeartFlow Analysis of Coronary Blood Flow Using Coronary CT Angiography: NeXt sTeps

Further study details as provided by HeartFlow, Inc.:

Primary Outcome Measures:
  • Primary Endpoint [ Time Frame: 1 day ] [ Designated as safety issue: No ]
    The area under the receiver operating characteristic curve (AUC of ROC) of a patient-based model intended to detect hemodynamically significant obstruction. FFR is used as the reference standard to determine the presence or absence of hemodynamically significant obstruction. cCTA stenosis will be calculated for each patient as the highest cCTA stenosis category for any vessel segment with diameter ≥2.0 mm. Only subjects with maximum cCTA stenosis in the range of 30 to 90% (as determined by the investigative site) in one or more vessel segments with diameter ≥2.0 mm will be included in the primary analysis.


Enrollment: 254
Study Start Date: September 2012
Study Completion Date: September 2013
Primary Completion Date: September 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: single arm
Single arm
Device: Measured FFR
Fractional Flow Reserve
Other Name: Fractional Flow Reserve

Detailed Description:

Recently, coronary Computed Tomography Angiography (cCTA) of 64-detector rows or greater has emerged as a novel non-invasive imaging modality that is capable of providing high-resolution images of coronary artery lesions (Budoff 2008; Miller 2008; Meijboom 2008). While cCTA demonstrates good diagnostic performance for detection and exclusion of anatomic coronary artery stenoses, numerous prior studies have revealed an unreliable relationship between detection of obstructive anatomic coronary artery stenoses by cCTA and hemodynamically (HD)-significant coronary artery disease (CAD), identified by myocardial perfusion SPECT or fractional flow reserve (FFR) (Di Carli 2007; Klauss 2007; Rispler 2007; van Werkhoven 2009). Individual subjects may have HD-significant CAD despite cCTA assessment demonstrating angiographically mild (<50%) maximal stenosis (Schuijf 2006). These findings emphasize the need for additional measures beyond anatomic stenosis severity for the detection and exclusion of HD-significant CAD.

Measurement of FFR during invasive cardiac catheterization represents the "gold standard" for assessment of the hemodynamic significance of coronary artery lesions (Kern 2010). Anatomic coronary artery stenosis assessment by quantitative coronary angiography (QCA) also correlates very poorly with FFR Melikian 2010). This was highlighted by the results of the FAME study in which FFR-guided coronary revascularization improved healthcare and economic outcomes compared to the conventional angiographically guided strategy (Pijls 2010; Tonino 2009; Tonino 2010).

The major disadvantage of FFR is that it has to be measured invasively. HeartFlow, Inc. ('HeartFlow') has recently developed a non-invasive method to determine FFR which computes the hemodynamic significance of CAD (FFRCT) from subject-specific cCTA data using computational fluid dynamics under rest and simulated maximal coronary hyperemic conditions. Preliminary results in subjects suggest that FFRCT accurately predicts the hemodynamic significance of coronary lesions when compared to directly-measured FFR during invasive cardiac catheterization (Koo 2011).

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • Age ≥18 years
  • Subject providing written informed consent
  • Scheduled to undergo a clinically indicated Invasive Coronary Angiogram (ICA)
  • Has had ≥64 multidetector row cCTA within 60 days prior to ICA or agrees to undergo cCTA with ≥64 multidetector row cCTA within 60 days prior to ICA

Exclusion Criteria:

  • Percutaneous coronary intervention (PCI) has been performed any time prior to ICA.
  • Prior coronary artery bypass graft (CABG) surgery
  • Contraindication to beta blocker agents, nitrates, or 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 30 days prior to cCTA or between cCTA and ICA
  • Known complex congenital heart disease
  • Prior pacemaker or internal defibrillator lead implantation
  • Prosthetic heart valve
  • Tachycardia or significant arrhythmia
  • Impaired chronic renal function (serum creatinine >1.5 mg/dl)
  • Subjects with known anaphylactic allergy to iodinated contrast
  • Pregnancy or unknown pregnancy status in subject of childbearing potential
  • Body mass index >35 at time of cCTA
  • Subject 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
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01757678

Locations
Denmark
Aarhus University Hospital
Arhus, Denmark
Sponsors and Collaborators
HeartFlow, Inc.
Case Western Reserve University
Investigators
Principal Investigator: Bjarne Norgaard, MD Aarhus University Hospital
  More Information