Fractional flow reserve calculation from 3-dimensional quantitative coronary angiography and TIMI frame count: a fast computer model to quantify the functional significance of moderately obstructed coronary arteries

JACC Cardiovasc Interv. 2014 Jul;7(7):768-77. doi: 10.1016/j.jcin.2014.03.004.


Objectives: This study sought to present a novel computer model for fast computation of myocardial fractional flow reserve (FFR) and to evaluate it in patients with intermediate coronary stenoses.

Background: FFR is an indispensable tool to identify individual coronary stenoses causing ischemia. Calculation of FFR from x-ray angiographic data may increase the utility of FFR assessment.

Methods: Consecutive patients with intermediate coronary stenoses undergoing pressure wire-based FFR measurements were analyzed by a core laboratory. Three-dimensional quantitative coronary angiography (QCA) was performed and the mean volumetric flow rate at hyperemia was calculated using TIMI (Thrombolysis In Myocardial Infarction) frame count combined with 3-dimensional QCA. Computational fluid dynamics was applied subsequently with a novel strategy for the computation of FFR. Diagnostic performance of the computed FFR (FFRQCA) was assessed using wire-based FFR as reference standard.

Results: Computation of FFRQCA was performed on 77 vessels in 68 patients. Average diameter stenosis was 46.6 ± 7.3%. FFRQCA correlated well with FFR (r = 0.81, p < 0.001), with a mean difference of 0.00 ± 0.06 (p = 0.541). Applying the FFR cutoff value of ≤0.8 to FFRQCA resulted in 18 true positives, 50 true negatives, 4 false positives, and 5 false negatives. The area under the receiver-operating characteristic curve was 0.93 for FFRQCA, 0.73 for minimum lumen area, and 0.65 for percent diameter stenosis.

Conclusions: Computation of FFRQCA is a novel method that allows the assessment of the functional significance of intermediate stenosis. It may emerge as a safe, efficient, and cost-reducing tool for evaluation of coronary stenosis severity during diagnostic angiography.

Keywords: cardiovascular physiology; computational fluid dynamics; fractional flow reserve; quantitative coronary angiography.

Publication types

  • Evaluation Study
  • Multicenter Study
  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Area Under Curve
  • Cardiac Catheterization
  • China
  • Computer Simulation
  • Coronary Angiography / methods*
  • Coronary Angiography / standards
  • Coronary Stenosis / diagnostic imaging*
  • Coronary Stenosis / physiopathology
  • Coronary Vessels / diagnostic imaging*
  • Coronary Vessels / physiopathology
  • False Negative Reactions
  • False Positive Reactions
  • Female
  • Fractional Flow Reserve, Myocardial*
  • Humans
  • Hungary
  • Hyperemia / diagnostic imaging
  • Hyperemia / physiopathology
  • Imaging, Three-Dimensional* / standards
  • Male
  • Middle Aged
  • Models, Cardiovascular
  • Myocardial Perfusion Imaging / methods*
  • Myocardial Perfusion Imaging / standards
  • Predictive Value of Tests
  • Prognosis
  • ROC Curve
  • Radiographic Image Interpretation, Computer-Assisted* / standards
  • Reference Standards
  • Retrospective Studies
  • Severity of Illness Index
  • Time Factors
  • Tomography, X-Ray Computed / methods*
  • Tomography, X-Ray Computed / standards