Plaque burden improves the detection of ischemic CAD over stenosis from coronary computed tomography angiography

Tanja Kero1,2, Sarah Bär3,4, Antti Saraste3,5

  • 1Department of Surgical Sciences, Nuclear Medicine & PET, Uppsala University, Uppsala, Sweden. tanja.kero@uu.se.

Insights

Quantifying plaque burden using percent atheroma volume (PAV) with coronary CT angiography (CTA) improves detection of ischemic coronary artery disease (CAD). This AI-guided approach offers incremental value beyond stenosis severity and clinical factors for patient-level diagnosis.

Area of Science:

  • Cardiovascular Imaging
  • Radiology
  • Artificial Intelligence in Medicine

Background:

  • Coronary artery disease (CAD) diagnosis relies on assessing luminal narrowing, but plaque burden may offer additional insights.
  • Coronary computed tomography angiography (CTA) is widely used for CAD evaluation.
  • Identifying ischemic CAD accurately is crucial for guiding patient management.

Purpose of the Study:

  • To evaluate if quantifying plaque burden via AI-guided quantitative CT (AI-QCT) provides incremental diagnostic value for ischemic CAD.
  • To compare the diagnostic performance of AI-QCT plaque metrics against traditional stenosis assessment and clinical risk factors.
  • To determine the optimal application of plaque quantification for improved patient-level CAD detection.

Main Methods:

  • 2145 symptomatic patients with suspected CAD underwent coronary CTA and 15O-water PET myocardial perfusion imaging.
  • AI-QCT was used to measure maximum diameter stenosis, percent atheroma volume (PAV), percent calcified plaque volume (CPV), and percent noncalcified plaque volume (NCPV).
  • Ischemic CAD was defined by abnormal stress perfusion on PET; diagnostic performance was assessed using Area Under the Curve (AUC) and predictive values.

Main Results:

  • Percent atheroma volume (PAV) significantly improved the prediction of ischemic CAD compared to clinical variables and stenosis alone (AUC 0.91 vs. 0.87).
  • Applying a PAV cut-off of 12.2% in patients with intermediate stenosis (30-70%) yielded the best diagnostic performance (88% accuracy).
  • This approach demonstrated high sensitivity (76%), specificity (91%), and negative predictive value (95%) for detecting ischemic CAD.

Conclusions:

  • Quantitative plaque burden assessment using AI-QCT, specifically PAV, offers incremental value for identifying ischemic CAD in symptomatic patients.
  • Integrating PAV measurement into coronary CTA analysis enhances diagnostic accuracy beyond traditional stenosis assessment.
  • A PAV threshold of 12.2% in intermediate stenosis cases provides optimal performance for detecting PET-defined ischemic CAD.