title: Additional value of associating aortic valve calcification to coronary calcium as a gatekeeper for coronary tomography angiography.
abstract: BACKGROUND
  Aortic valve calcification shares risk factors with coronary artery disease. Coronary calcium has been used has a gatekeeper to performing coronary tomography angiography. The aim of this study was to evaluate aortic valve calcification as a predictor of obstructive coronary artery disease by computed tomography, and its possible usefulness, alongside with coronary calcium, to improve the decision of whether or not to proceed with computed tomography angiography.
  
  
  METHODS
  Transversal case-control study including 154 consecutive patients (62 ± 12 years, 57.6 % female, without known coronary or valve disease) undergoing calcium scoring and angiography through computed tomography (Phillips Brilliance, 16-slice). Predictors of aortic valve calcification and obstructive coronary artery disease were identified. Usefulness of aortic valve calcification when added to calcium score for prediction of obstructive coronary artery disease was assessed by binary logistic regression and net reclassification index.
  
  
  RESULTS
  Aortic valve calcification was associated with higher coronary calcium, extent and prevalence of obstructive coronary disease, which was identified in 22.1 % of patients and was discriminated by aortic valve calcium with an area under curve 0.749 (p < 0.001, Youden index: 61). A higher discriminative power was achieved with a model based on coronary and aortic valve calcification (AUC 0.900, p < 0.001). Compared with calcium score >400 as a gatekeeper to angiography, the association of aortic calcium >61 allowed a net reclassification index of +7.7 % of patients.
  
  
  CONCLUSIONS
  Aortic valve calcification is associated with the prevalence and extent of obstructive coronary artery disease by computed tomography angiography and is an easy, fast and useful method to improve the selection of patients for angiography.
authors.affiliation: Cardiology Department, Coimbra's Hospital and University Centre - General Hospital, 3041-801 S. Martinho do Bispo, Coimbra, Portugal. anacatarina.faustino@gmail.com.
authors.forename: Ana
authors.initials: A
authors.lastname: Faustino
authors.affiliation: Cardiology Department, Coimbra's Hospital and University Centre - General Hospital, 3041-801 S. Martinho do Bispo, Coimbra, Portugal. ruiprovidencia@yahoo.com.|Faculty of Medicine, University of Coimbra, Coimbra, Portugal. ruiprovidencia@yahoo.com.
authors.forename: Rui
authors.initials: R
authors.lastname: Providência
authors.affiliation: Cardiology Department, Coimbra's Hospital and University Centre - General Hospital, 3041-801 S. Martinho do Bispo, Coimbra, Portugal. luisvpaiva@gmail.com.
authors.forename: Luís
authors.initials: L
authors.lastname: Paiva
authors.affiliation: Radiology Department, Coimbra's Hospital and University Centre - General Hospital, Coimbra, Portugal. rpdnc@netcabo.pt.
authors.forename: Rui
authors.initials: R
authors.lastname: Catarino
authors.affiliation: Radiology Department, Coimbra's Hospital and University Centre - General Hospital, Coimbra, Portugal. spfbasso@yahoo.com.
authors.forename: Susana
authors.initials: S
authors.lastname: Basso
authors.affiliation: Cardiology Department, Coimbra's Hospital and University Centre - General Hospital, 3041-801 S. Martinho do Bispo, Coimbra, Portugal. marcocostacard@sapo.pt.
authors.forename: Marco
authors.initials: M
authors.lastname: Costa
authors.affiliation: Cardiology Department, Coimbra's Hospital and University Centre - General Hospital, 3041-801 S. Martinho do Bispo, Coimbra, Portugal. dir.cardiologia@chc.min-saude.pt.|Faculty of Medicine, University of Coimbra, Coimbra, Portugal. dir.cardiologia@chc.min-saude.pt.
authors.forename: Lino
authors.initials: L
authors.lastname: Gonçalves
mesh_terms: D000368:Aged; D001021:Aortic Valve / Q000000981:diagnostic imaging / Q000473:pathology*; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging*; D000082882:Bicuspid Aortic Valve Disease; D002114:Calcinosis / Q000000981:diagnostic imaging*; D016022:Case-Control Studies; D015331:Cohort Studies; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000000981:diagnostic imaging; D023921:Coronary Stenosis / Q000175:diagnosis / Q000000981:diagnostic imaging*; D005260:Female; D006330:Heart Defects, Congenital / Q000000981:diagnostic imaging*; D006349:Heart Valve Diseases / Q000000981:diagnostic imaging*; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D061205:Vascular Calcification / Q000000981:diagnostic imaging*