title: Improving the relationship between coronary artery calcium score and coronary plaque burden: addition of regional measures of coronary artery calcium distribution.
abstract: BACKGROUND
  The Agatston coronary artery calcium (CAC) score predicts cardiovascular events through its association with overall burden of coronary atherosclerosis. It is unclear whether adding regional measures of CAC distribution to the Agatston score improves this association.
  
  
  METHODS
  We studied 920 consecutive patients (mean age 57 ± 12, 53% female), referred for 64-slice Coronary CT angiography (CCTA) who had concomitant CAC scoring. Total atherosclerosis burden was quantified as the segment involvement score (SIS), which describes the number of coronary segments with plaque on CCTA. We studied the heterogeneity between CAC group (0, 1-100, 101-400, >400) and the number of vessels with CAC (0-4), and related this to SIS on CCTA. In patients with multi-vessel disease, we examined the relationship of concentrated vs. diffuse CAC (> or ≤75% total CAC in one vessel) with SIS.
  
  
  RESULTS
  When CAC was intermediate (1-400), considerable heterogeneity was noted between CAC group and the number of vessels with CAC (CAC 1-100: 53% 1-vessel, 29% 2-vessel, 16% 3-vessel, 2% 4-vessel; CAC 101-400: 9% 1-vessel, 28% 2-vessel, 43% 3-vessel, 20% 4-vessel). Within each CAC group, increase in the number of vessels with CAC was significantly associated with increased SIS. In multi-vessel disease, a higher SIS was associated with diffuse versus concentrated CAC (CAC 1-100: 3.8 vs. 2.8, CAC 101-400: 5.5 vs. 4.3 [both p < 0.01]). These associations persisted after adjustment for age, gender, and the absolute Agatston CAC score (p < 0.01).
  
  
  CONCLUSIONS
  Addition of measures of regional CAC distribution improves the association of the Agatston CAC score with total plaque burden.
authors.affiliation: Johns Hopkins Ciccarone Center for the Prevention of Heart Disease, Carnegie 565A, Johns Hopkins Hospital, 600 N. Wolfe Street, Baltimore, MD 21287, USA; Danbury Hospital, 24 Hospital Avenue, Danbury, CT 06810, USA.
authors.forename: Rajesh
authors.initials: R
authors.lastname: Tota-Maharaj
authors.affiliation: Henry Ford Hospital/Wayne State University, 2799 W Grand Blvd, Detroit, MI 48202, USA; King Abdul-Aziz Cardiac Center, King Abdul-Aziz Medical City, Riyadh, Saudi Arabia.
authors.forename: Mouaz H
authors.initials: MH
authors.lastname: Al-Mallah
authors.affiliation: Johns Hopkins Ciccarone Center for the Prevention of Heart Disease, Carnegie 565A, Johns Hopkins Hospital, 600 N. Wolfe Street, Baltimore, MD 21287, USA; Baptist Health South Florida, 1691 Michigan Avenue Suite 500, Miami Beach, FL 33139, USA.
authors.forename: Khurram
authors.initials: K
authors.lastname: Nasir
authors.affiliation: Wake Forest University School of Medicine, Medical Center Blvd, Winston-Salem, NC 27157, USA.
authors.forename: Waqas T
authors.initials: WT
authors.lastname: Qureshi
authors.affiliation: Johns Hopkins Ciccarone Center for the Prevention of Heart Disease, Carnegie 565A, Johns Hopkins Hospital, 600 N. Wolfe Street, Baltimore, MD 21287, USA.
authors.forename: Roger S
authors.initials: RS
authors.lastname: Blumenthal
authors.affiliation: Johns Hopkins Ciccarone Center for the Prevention of Heart Disease, Carnegie 565A, Johns Hopkins Hospital, 600 N. Wolfe Street, Baltimore, MD 21287, USA. Electronic address: mblaha1@jhmi.edu.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Blaha
mesh_terms: D000368:Aged; D000465:Algorithms; D050197:Atherosclerosis / Q000175:diagnosis* / Q000000981:diagnostic imaging; D002114:Calcinosis / Q000175:diagnosis* / Q000000981:diagnostic imaging; D002118:Calcium / Q000737:chemistry*; D017023:Coronary Angiography; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000473:pathology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000175:diagnosis / Q000000981:diagnostic imaging; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed
chemical_list: D002118:Calcium
keywords: Coronary artery calcium; Coronary artery disease; Coronary computed tomography angiography