title: Incremental value of a single high-sensitivity cardiac troponin I measurement to rule out myocardial ischemia.
abstract: BACKGROUND
  The aim of this study was to investigate the value of a novel high-sensitivity cardiac troponin I measurement to rule out exercise-induced myocardial ischemia in patients without known coronary artery disease.
  
  
  METHODS
  We included 714 patients without previously known coronary artery disease who were referred for rest/stress myocardial perfusion single photon emission tomography. All clinical information available to the treating cardiologist was used to quantify the clinical judgment regarding the presence of exercise-induced myocardial ischemia using a visual analogue scale twice: once before and once after bicycle exercise stress testing. High-sensitivity cardiac troponin I measurements were obtained before stress testing in a blinded manner. The presence of exercise-induced myocardial ischemia was adjudicated on the basis of myocardial perfusion single photon emission tomography combined with coronary angiography findings.
  
  
  RESULTS
  Exercise-induced myocardial ischemia was detected in 167 participants (23.4%). High-sensitivity cardiac troponin I levels were significantly higher in patients with exercise-induced myocardial ischemia (4.0 ng/L [95% confidence interval, 2.8-8.6] vs 2.6 ng/L [95% confidence interval, 1.8-4.1], P < .001) and remained an independent predictor of ischemia in multivariable analysis (P < .001). Combining clinical judgment before exercise testing with high-sensitivity cardiac troponin I levels increased diagnostic accuracy as quantified by the area under the receiver operating curve from 0.64 to 0.73 (P < .001), which also tended to be superior to clinical judgment after exercise testing (0.69, P = .056). A single resting high-sensitivity cardiac troponin I measurement provided similar diagnostic accuracy as integrated clinical judgment after exercise testing including work load, as well as symptoms and electrocardiogram changes (0.70 vs 0.69, P = not significant).
  
  
  CONCLUSIONS
  High-sensitivity cardiac troponin I measurements seem to complement noninvasive clinical assessment in patients with suspected coronary artery disease.
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Yunus
authors: Y
authors: Tanglay
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland; Department of Internal Medicine, University Hospital Basel, Switzerland.
authors: Raphael
authors: R
authors: Twerenbold
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Gino
authors: G
authors: Lee
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Max
authors: M
authors: Wagener
authors: Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Ursina
authors: U
authors: Honegger
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Christian
authors: C
authors: Puelacher
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Tobias
authors: T
authors: Reichlin
authors: Seoung
authors: S
authors: Mann
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland; Department of Internal Medicine, University Hospital Basel, Switzerland.
authors: Seoung Man
authors: SM
authors: Sou
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Sophie
authors: S
authors: Druey
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland; Department of Internal Medicine, University Hospital Basel, Switzerland.
authors: Thomas
authors: T
authors: Hochgruber
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Stephan
authors: S
authors: Zürcher
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Milos
authors: M
authors: Radosavac
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Philipp
authors: P
authors: Kreutzinger
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Gilles
authors: G
authors: Pretre
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Fabio
authors: F
authors: Stallone
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Petra
authors: P
authors: Hillinger
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Cedric
authors: C
authors: Jaeger
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Maria
authors: M
authors: Rubini Gimenez
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Michael
authors: M
authors: Freese
authors: Division of Nuclear Medicine, University Hospital Basel, Switzerland.
authors: Damian
authors: D
authors: Wild
authors: Department of Laboratory Medicine, University Hospital Basel, Switzerland.
authors: Katharina
authors: K
authors: Rentsch
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Stefan
authors: S
authors: Osswald
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors: Michael J
authors: MJ
authors: Zellweger
authors: Department of Cardiology, University Hospital Basel, Switzerland; Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland. Electronic address: christian.mueller@usb.ch.
authors: Christian
authors: C
authors: Mueller
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D003324:Coronary Artery Disease / Q000097:blood / Q000175:diagnosis; D015444:Exercise; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017202:Myocardial Ischemia / Q000097:blood* / Q000175:diagnosis*; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012044:Regression Analysis; D019210:Troponin I / Q000097:blood*
chemical_list: D015415:Biomarkers; D019210:Troponin I
keywords: Exercise; High-sensitivity cardiac troponin I; Ischemia; Perfusion; Single photon emission tomography