Trial Outcomes & Findings for Determination of Fractional Flow Reserve by Anatomic Computed Tomographic Angiography (NCT NCT01233518)

NCT ID: NCT01233518

Last Updated: 2021-02-09

Results Overview

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.

• Recruitment status: COMPLETED
• Study phase: NA
• Target enrollment: 285 participants
• Primary outcome timeframe: 1 day
• Results posted on: 2021-02-09

Participant Flow

Participant milestones

Measure	Single Arm Study Patients will receive cCTA, ICA, FFR, and cFFR per protocol. FFR: Fractional flow reserve measured during cardiac catheterization
Overall Study STARTED	285
Overall Study COMPLETED	252
Overall Study NOT COMPLETED	33

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Determination of Fractional Flow Reserve by Anatomic Computed Tomographic Angiography

Baseline characteristics by cohort

Measure	Single Arm Study n=252 Participants Patients will receive cCTA, ICA, FFR, and cFFR per protocol. FFR: Fractional flow reserve measured during cardiac catheterization
Age, Categorical <=18 years	0 Participants n=5 Participants
Age, Categorical Between 18 and 65 years	135 Participants n=5 Participants
Age, Categorical >=65 years	117 Participants n=5 Participants
Sex: Female, Male Female	74 Participants n=5 Participants
Sex: Female, Male Male	178 Participants n=5 Participants
Region of Enrollment United States	92 Participants n=5 Participants
Region of Enrollment Belgium	43 Participants n=5 Participants
Region of Enrollment Canada	1 Participants n=5 Participants
Region of Enrollment Latvia	41 Participants n=5 Participants
Region of Enrollment South Korea	75 Participants n=5 Participants

PRIMARY outcome

Timeframe: 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.

Outcome measures

Measure	Single Arm Study n=252 Participants Per-patient performance (diagnostic accuracy) CCTA plus FFRCT
Percentage of Participants With Diagnostic Accuracy of CCTA Plus FFRCT and CCTA Alone Accuracy of FFRCT	73 percentage of participants Interval 67.0 to 78.0
Percentage of Participants With Diagnostic Accuracy of CCTA Plus FFRCT and CCTA Alone Accuracy of CCTA	64 percentage of participants Interval 58.0 to 70.0

SECONDARY outcome

Timeframe: 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.

Outcome measures

Measure	Single Arm Study n=252 Participants Per-patient performance (diagnostic accuracy) CCTA plus FFRCT
Diagnostic Performance of CCTA Plus FFRCT at the Subject Level Sensitivity	90 percentage of participants Interval 84.0 to 95.0
Diagnostic Performance of CCTA Plus FFRCT at the Subject Level Specificity	54 percentage of participants Interval 46.0 to 83.0
Diagnostic Performance of CCTA Plus FFRCT at the Subject Level Positive predictive value	67 percentage of participants Interval 60.0 to 74.0
Diagnostic Performance of CCTA Plus FFRCT at the Subject Level Negative predictive value	84 percentage of participants Interval 74.0 to 90.0

Adverse Events

Single Arm Study

Serious events: 2 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Measure	Single Arm Study n=252 participants at risk Patients will receive cCTA, ICA, FFR, and cFFR per protocol. FFR: Fractional flow reserve measured during cardiac catheterization
Vascular disorders Retroperitoneal bleed	0.40% 1/252 • Number of events 1
Vascular disorders Hypotension	0.40% 1/252 • Number of events 1
Blood and lymphatic system disorders Septic shock	0.40% 1/252 • Number of events 1

Other adverse events

Adverse event data not reported

Additional Information

Whitney Huey

Heartflow, Inc.

Phone: 650.257.6697

Email: whuey@heartflow.com

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place