title: Differential Prognostic Value of Coronary Computed Tomography Angiography in Relation to Exercise Electrocardiography in Asymptomatic Subjects.
abstract: BACKGROUND
  To explore the prognostic performance of coronary computed tomography angiography (CCTA) and exercise electrocardiography (XECG) in asymptomatic subjects.
  
  
  METHODS
  We retrospectively enrolled 812 (59 ± 9 years, 60.8% male) asymptomatic subjects who underwent CCTA and XECG concurrently from 2003 through 2009. Subjects were followed-up for major adverse cardiac events (MACE) including cardiac death, nonfatal myocardial infarction, unstable angina, and revascularization after 90 days from index CCTA.
  
  
  RESULTS
  The prevalence of occult coronary artery disease (CAD) detected by CCTA was 17.5% and 120 subjects (14.8%) had positive XECG. During a mean follow-up of 37 ± 16 months, nine subjects experienced MACE. In multivariable Cox-regression analysis, only the presence of CAD by CCTA independently predicted future MACE (p = 0.002). Moreover, CAD by CCTA improved the predictive value when added to a clinical risk factor model using the likelihood ratio test (p < 0.001). Notably, the prognostic value of CCTA persisted in the moderate-to-high-risk group as classified by the Duke treadmill score (p = 0.040), but not in the low-risk group (p = 0.991).
  
  
  CONCLUSIONS
  CCTA provides incremental prognostic benefit over and above XECG in an asymptomatic population, especially for those in a moderate-to-high-risk group as classified by the Duke treadmill score. Risk stratification using XECG may prove valuable for identifying asymptomatic subjects who can benefit from CCTA.
authors.affiliation: Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Yonsei University Health System, Seoul, Korea.
authors.forename: Sang-Eun
authors.initials: SE
authors.lastname: Lee
authors.affiliation: Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Yonsei University Health System, Seoul, Korea.
authors.forename: Iksung
authors.initials: I
authors.lastname: Cho
authors.affiliation: Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Yonsei University Health System, Seoul, Korea.
authors.forename: Geu-Ru
authors.initials: GR
authors.lastname: Hong
authors.affiliation: Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Yonsei University Health System, Seoul, Korea.; Severance Biomedical Science Institute, Yonsei University Health System, Seoul, Korea.
authors.forename: Hyuk-Jae
authors.initials: HJ
authors.lastname: Chang
authors.affiliation: Department of Research Affairs, Yonsei University College of Medicine, Yonsei University Health System, Seoul, Korea.
authors.forename: Ji Min
authors.initials: JM
authors.lastname: Sung
authors.affiliation: Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Yonsei University Health System, Seoul, Korea.
authors.forename: In-Jeong
authors.initials: IJ
authors.lastname: Cho
authors.affiliation: Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Yonsei University Health System, Seoul, Korea.
authors.forename: Chi Young
authors.initials: CY
authors.lastname: Shim
authors.affiliation: Division of Radiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Byoung Wook
authors.initials: BW
authors.lastname: Choi
authors.affiliation: Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Yonsei University Health System, Seoul, Korea.
authors.forename: Namsik
authors.initials: N
authors.lastname: Chung
keywords: Asymptomatic population; Coronary artery disease; Coronary computed tomography angiography; Exercise electrocardiography