title: A peripheral blood gene expression score is associated with plaque volume and phenotype by intravascular ultrasound with radiofrequency backscatter analysis: results from the ATLANTA study.
abstract: BACKGROUND
  A composite, peripheral gene expression score based on quantitative RNA-measurements has been validated for detecting stenosis against invasive coronary X-ray angiography. IVUS/VH has been validated for quantitative measurements of coronary plaque volume and composition and has been shown to be predictive of outcomes and treatment effects. The correlation between peripheral gene expression and coronary plaque composition by intravascular ultrasound with radiofrequency backscatter (IVUS/VH) is unknown.
  
  
  METHODS
  Peripheral blood gene expression score (GES) was prospectively measured in 18 patients undergoing IVUS/VH. Plaque volume and composition [fibrous tissue (FI), fibro-fatty tissue (FF), necrotic core (NC) and dense calcium (DC)] were quantified in 3 dimensions in all plaques within the entire pullback. The relationship to GES was assessed by Spearman rank correlation.
  
  
  RESULTS
  Mean age was 61.1±8.6 years; 67% were male. 1,158 mm of coronary anatomy was imaged by IVUS/VH. Using a validated scale of 1-40, mean GES was 21.6±9.4. GES was associated with plaque volume (R(2)=0.55; P=0.018), NC volume (R(2)=0.56; P=0.015), DC volume (R(2)=0.60; P=0.007), and non-calcified plaque volume (R(2)=0.50; P=0.036) by Spearman rank correlation.
  
  
  CONCLUSIONS
  In this preliminary report, increased GES was associated with higher plaque volume and a more vulnerable plaque phenotype as evidenced by NC and DC. This composite GES is not only associated with obstructive coronary disease, but also with higher plaque volume and vulnerable phenotype.
authors.affiliation: Piedmont Heart Institute, Atlanta, GA 30309, USA;
authors.forename: Parag H
authors.initials: PH
authors.lastname: Joshi
authors.forename: Sarah
authors.initials: S
authors.lastname: Rinehart
authors.forename: Gustavo
authors.initials: G
authors.lastname: Vazquez
authors.forename: Zhen
authors.initials: Z
authors.lastname: Qian
authors.forename: Abhinav
authors.initials: A
authors.lastname: Sharma
authors.forename: Hunt
authors.initials: H
authors.lastname: Anderson
authors.forename: Laura
authors.initials: L
authors.lastname: Murrieta
authors.forename: Nancy
authors.initials: N
authors.lastname: Flockhart
authors.forename: Dimitri
authors.initials: D
authors.lastname: Karmpaliotis
authors.forename: Anna
authors.initials: A
authors.lastname: Kalynych
authors.forename: Bela
authors.initials: B
authors.lastname: Asztalos
authors.forename: Michael R
authors.initials: MR
authors.lastname: Elashoff
authors.forename: John
authors.initials: J
authors.lastname: Blanchard
authors.forename: Steven
authors.initials: S
authors.lastname: Rosenberg
authors.forename: Charles
authors.initials: C
authors.lastname: Brown
authors.forename: Szilard
authors.initials: S
authors.lastname: Voros
keywords: Gene expression; intravascular ultrasound; necrotic core; plaque volume; vulnerable plaque