Definitions and methodology for the grayscale and radiofrequency intravascular ultrasound and coronary angiographic analyses

JACC Cardiovasc Imaging. 2012 Mar;5(3 Suppl):S1-9. doi: 10.1016/j.jcmg.2011.11.019.


Objectives: In a prospective study of the natural history of coronary atherosclerosis using angiography and grayscale and radiofrequency intravascular ultrasound (IVUS)-virtual histology (VH), larger plaque burden, smaller luminal area, and plaque composition thin-cap fibroatheroma emerged as independent predictors of future adverse cardiovascular events.

Background: The methodology for IVUS-VH classification for an in vivo natural history study and the prospective image mapping by angiography and grayscale and IVUS-VH have not been established.

Methods: All culprit and nonculprit lesions (defined as ≥ 30% angiographic visual diameter stenoses) were analyzed. Three epicardial vessels as well as all ≥ 1.5-mm-diameter side branches were divided into 29 CASS (Coronary Artery Surgery Study) segments. Each CASS segment was then subdivided into 1.5-mm-long subsegments, and dimensions were analyzed. All grayscale and IVUS-VH slices from the proximal 6 to 8 cm of the 3 coronary arteries were analyzed, with lesions defined as having more than 3 consecutive slices with ≥ 40% plaque burden categorized as: 1) VH thin-cap fibroatheroma; 2) thick-cap fibroatheroma; 3) pathological intimal thickening; 4) fibrotic plaque; or 5) fibrocalcific plaque. The locations of angiographic and grayscale and IVUS-VH lesions were recorded in relation to the corresponding coronary artery ostium and nearby side branches.

Results: The 3-year cumulative rate of major adverse cardiovascular events was 20.4%. Events were adjudicated to culprit lesions in 12.9% of patients and to nonculprit lesions in 11.6%. On multivariate analysis, nonculprit lesions associated with recurrent events were characterized by a plaque burden ≥ 70% (hazard ratio: 5.03; 95% confidence interval: 2.51 to 10.11; p < 0.0001), a minimal luminal area ≤ 4.0 mm(2) (hazard ratio: 3.21; 95% confidence interval: 1.61 to 6.42; p = 0.001), and IVUS-VH phenotype of a thin-cap fibroatheroma (hazard ratio: 3.35; 95% confidence interval: 1.77 to 6.36; p < 0.001).

Conclusions: Three-vessel multimodality coronary artery imaging was feasible and allowed the identification of lesion-level predictors for future events in this natural history study.

Trial registration: NCT00180466.

Publication types

  • Multicenter Study

MeSH terms

  • Aged
  • Angioplasty, Balloon, Coronary / adverse effects
  • Angioplasty, Balloon, Coronary / mortality
  • Coronary Angiography* / standards
  • Coronary Artery Disease / classification
  • Coronary Artery Disease / diagnostic imaging*
  • Coronary Artery Disease / mortality
  • Coronary Artery Disease / therapy
  • Coronary Stenosis / classification
  • Coronary Stenosis / diagnostic imaging*
  • Coronary Stenosis / mortality
  • Coronary Stenosis / therapy
  • Disease Progression
  • Europe / epidemiology
  • Female
  • Fibrosis
  • Humans
  • Image Processing, Computer-Assisted / standards
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Neointima / diagnostic imaging
  • Predictive Value of Tests
  • Prospective Studies
  • Risk Assessment
  • Risk Factors
  • Severity of Illness Index
  • Terminology as Topic
  • Time Factors
  • Treatment Outcome
  • Ultrasonography, Interventional* / standards
  • United States / epidemiology
  • Vascular Calcification / diagnostic imaging

Associated data