title: Prognostic significance of calcified plaque among symptomatic patients with nonobstructive coronary artery disease.
abstract: BACKGROUND
  Coronary artery calcium (CAC) is a well-established predictor of clinical outcomes for population screening. Limited evidence is available as to its predictive value in symptomatic patients without obstructive coronary artery disease (CAD). The aim of the current study was to assess the prognostic value of CAC scores among symptomatic patients with nonobstructive CAD.
  
  
  METHODS
  From the COronary Computed Tomographic Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter (CONFIRM) registry, 7,200 symptomatic patients with nonobstructive CAD (<50% coronary stenosis) on coronary-computed tomographic angiography were prospectively enrolled and followed for a median of 2.1 years. Patients were categorized as without (0% stenosis) or with (>0% but <50% coronary stenosis) a luminal stenosis. CAC scores were calculated using the Agatston method. Univariable and multivariable Cox proportional hazard models were employed to estimate all-cause mortality and/or myocardial infarction (MI). Four-year death and death or MI rates were 1.9% and 3.3%.
  
  
  RESULTS
  Of the 4,380 patients with no luminal stenosis, 86% had CAC scores of <10 while those with a luminal stenosis had more prevalent and extensive CAC with 31.9% having a CAC score of ≥100. Among patients with no luminal stenosis, CAC was not predictive of all-cause mortality (P = .44). However, among patients with a luminal stenosis, 4-year mortality rates ranged from 0.8% to 9.8% for CAC scores of 0 to ≥400 (P < .0001). The mortality hazard was 6.0 (P = .004) and 13.3 (P < .0001) for patients with a CAC score of 100-399 and ≥400. In patients with a luminal stenosis, CAC remained independently predictive in all-cause mortality (P < .0001) and death or MI (P < .0001) in multivariable models containing CAD risk factors and presenting symptoms.
  
  
  CONCLUSIONS
  CAC allows for the identification of those at an increased hazard for death or MI in symptomatic patients with nonobstructive disease. From the CONFIRM registry, the extent of CAC was an independent estimator of long-term prognosis among symptomatic patients with luminal stenosis and may further define risk and guide preventive strategies in patients with nonobstructive CAD.
authors.affiliation: Department of Medicine, Emory Clinical Cardiovascular Research Institute, Emory University School of Medicine, 1462 Clifton Road NE, Room 529, Atlanta, GA, USA.
authors.forename: Sana
authors.initials: S
authors.lastname: Shah
authors.forename: Naveen
authors.initials: N
authors.lastname: Bellam
authors.forename: Jonathon
authors.initials: J
authors.lastname: Leipsic
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Berman
authors.forename: Arshed
authors.initials: A
authors.lastname: Quyyumi
authors.forename: Jörg
authors.initials: J
authors.lastname: Hausleiter
authors.forename: Stephan
authors.initials: S
authors.lastname: Achenbach
authors.forename: Mouaz
authors.initials: M
authors.lastname: Al-Mallah
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Budoff
authors.forename: Fillippo
authors.initials: F
authors.lastname: Cademartiri
authors.forename: Tracy Q
authors.initials: TQ
authors.lastname: Callister
authors.forename: Hyuk-Jae
authors.initials: HJ
authors.lastname: Chang
authors.forename: Benjamin J W
authors.initials: BJ
authors.lastname: Chow
authors.forename: Ricardo C
authors.initials: RC
authors.lastname: Cury
authors.forename: Augustin J
authors.initials: AJ
authors.lastname: Delago
authors.forename: Allison L
authors.initials: AL
authors.lastname: Dunning
authors.forename: Gudrun M
authors.initials: GM
authors.lastname: Feuchtner
authors.forename: Martin
authors.initials: M
authors.lastname: Hadamitzky
authors.forename: Ronald P
authors.initials: RP
authors.lastname: Karlsberg
authors.forename: Philipp A
authors.initials: PA
authors.lastname: Kaufmann
authors.forename: Fay Y
authors.initials: FY
authors.lastname: Lin
authors.forename: Kavitha M
authors.initials: KM
authors.lastname: Chinnaiyan
authors.forename: Erica
authors.initials: E
authors.lastname: Maffei
authors.forename: Gilbert L
authors.initials: GL
authors.lastname: Raff
authors.forename: Todd C
authors.initials: TC
authors.lastname: Villines
authors.forename: Millie J
authors.initials: MJ
authors.lastname: Gomez
authors.forename: James K
authors.initials: JK
authors.lastname: Min
authors.forename: Leslee J
authors.initials: LJ
authors.lastname: Shaw
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D002415:Cats; D015984:Causality; D015897:Comorbidity; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000401:mortality*; D005260:Female; D006801:Humans; D038622:Internationality; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011379:Prognosis; D016016:Proportional Hazards Models; D011877:Radionuclide Imaging; D012042:Registries; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods; D012680:Sensitivity and Specificity; D017678:Sex Distribution; D015996:Survival Rate; D063189:Symptom Assessment; D061205:Vascular Calcification / Q000000981:diagnostic imaging* / Q000401:mortality*