Distal-vessel fractional flow reserve by computed tomography to monitor epicardial coronary artery disease

Eur Heart J Cardiovasc Imaging. 2024 Jan 29;25(2):163-172. doi: 10.1093/ehjci/jead229.

Abstract

Aims: Coronary computed tomography angiography (CTA) and fractional flow reserve by computed tomography (FFR-CT) are increasingly utilized to characterize coronary artery disease (CAD). We evaluated the feasibility of distal-vessel FFR-CT as an integrated measure of epicardial CAD that can be followed serially, assessed the CTA parameters that correlate with distal-vessel FFR-CT, and determined the combination of clinical and CTA parameters that best predict distal-vessel FFR-CT and distal-vessel FFR-CT changes.

Methods and results: Patients (n = 71) who underwent serial CTA scans at ≥2 years interval (median = 5.2 years) over a 14-year period were included in this retrospective study. Coronary arteries were analysed blindly using artificial intelligence-enabled quantitative coronary CTA. Two investigators jointly determined the anatomic location and corresponding distal-vessel FFR-CT values at CT1 and CT2. A total of 45.3% had no significant change, 27.8% an improvement, and 26.9% a worsening in distal-vessel FFR-CT at CT2. Stepwise multiple logistic regression analysis identified a four-parameter model consisting of stenosis diameter ratio, lumen volume, low density plaque volume, and age, that best predicted distal-vessel FFR-CT ≤ 0.80 with an area under the curve (AUC) = 0.820 at CT1 and AUC = 0.799 at CT2. Improvement of distal-vessel FFR-CT was captured by a decrease in high-risk plaque and increases in lumen volume and remodelling index (AUC = 0.865), whereas increases in stenosis diameter ratio, medium density calcified plaque volume, and total cholesterol presaged worsening of distal-vessel FFR-CT (AUC = 0.707).

Conclusion: Distal-vessel FFR-CT permits the integrative assessment of epicardial atherosclerotic plaque burden in a vessel-specific manner and can be followed serially to determine changes in global CAD.

Keywords: FFR-CT; coronary CT angiogram; coronary artery disease; plaque characteristics; total plaque burden.

MeSH terms

  • Artificial Intelligence
  • Computed Tomography Angiography
  • Constriction, Pathologic
  • Coronary Angiography / methods
  • Coronary Artery Disease* / diagnostic imaging
  • Coronary Stenosis* / diagnostic imaging
  • Fractional Flow Reserve, Myocardial*
  • Humans
  • Plaque, Atherosclerotic* / diagnostic imaging
  • Predictive Value of Tests
  • ROC Curve
  • Retrospective Studies
  • Tomography, X-Ray Computed