title: Noise versus signal: the clinical implications of an increasingly sensitive troponin assay for patients with suspected acute coronary syndrome.
abstract: OBJECTIVE
  To evaluate the clinical impact of a troponin assay switch in suspected acute coronary syndromes (ACS).
  
  
  METHODS
  Retrospective analysis of ACS cases in the 3 months before and after changing to a contemporary, higher sensitivity troponin assay. Admitting diagnosis, proportion with a positive result, initial treatment and testing, coronary artery intervention, inhospital events, and final discharge diagnosis were compared by assay group.
  
  
  RESULTS
  Seven hundred seventy patients were included: 319 (41.4%) preassay and 451 (58.6%) postassay. Preassay change, non-ST segment elevation myocardial infarction at admission (43.0% vs. 70.5%; diff [95% confidence interval (CI)] = -27.5 [-34.2, -20.6]) was diagnosed less often, and a positive troponin was less common (33.2% vs. 72.3%; diff [95% CI] = -39.1 [-45.4, -32.2]). However, anticoagulation (53.3% vs. 42.4%; diff [95% CI] = 10.9 [3.8, 18.0]) and cardiac catheterization use were more frequent (53.9% vs. 41.9%; diff [95% CI] = 12.0 [19.0, 48.5]). There was no difference in coronary intervention (41.9% vs. 40.7%; diff [95% CI] = 1.2 [-9.0, 11.2]) by assay period. Inhospital event were rare (unstable ventricular arrhythmia = 1.2%, cardiac arrest = 3.4%, death = 4.4%) with no difference between groups. A non-ACS diagnosis at discharge was more common in the postassay group (31.6% vs. 46.5%; diff [95% CI] = 14.9 [7.9, 21.6]).
  
  
  CONCLUSIONS
  Although non-ST segment elevation myocardial infarction diagnosis at admission and a positive troponin were more frequent postassay change, rates of anticoagulation and cardiac catheterization were lower and a non-ACS diagnosis at discharge was more common. These data suggest an evolving understanding and clinical impact of contemporary troponin assays when used in real-world settings.
authors: From the *Department of Emergency Medicine, Emory University, Atlanta GA; †Department of Internal Medicine, Wayne State University, Detroit, MI; ‡Department of Emergency Medicine, Metro Health Hospital-Statewide Campus System, Michigan State University College of Osteopathic Medicine, Wyoming, MI; §Oakwood Heritage Transitional Year Residency Program/Oakwood Healthcare, Taylor, MI; ¶Department of Internal Medicine, Loma Linda University, Loma Linda, CA; ‖Department of Emergency Medicine, St. John Hospital and Medical Center, Detroit, MI; **Department of Internal Medicine, California Pacific Medical Center, San Francisco, CA; ††Wayne State University School of Medicine, Detroit, MI; ‡‡Department of Emergency Medicine, Wayne State University School of Medicine, Detroit, MI; and §§Cardiovascular Research Institute, Wayne State University School of Medicine, Detroit, MI.
authors: Sarah
authors: S
authors: Wolf
authors: Ramanjit
authors: R
authors: Kaur
authors: William Patrick
authors: WP
authors: McKeown
authors: Helen
authors: H
authors: Chan
authors: Allen
authors: A
authors: Dang
authors: Trevor
authors: T
authors: Kuston
authors: Waihin
authors: W
authors: Leung
authors: John
authors: J
authors: Purakal
authors: Brian J
authors: BJ
authors: O'Neil
authors: Phillip
authors: P
authors: Levy
mesh_terms: D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use; D006328:Cardiac Catheterization / Q000706:statistics & numerical data; D003955:Diagnostic Tests, Routine / Q000379:methods / Q000706:statistics & numerical data; D004562:Electrocardiography; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods; D009203:Myocardial Infarction / Q000097:blood / Q000175:diagnosis / Q000401:mortality / Q000601:surgery; D017063:Outcome Assessment, Health Care; D010351:Patient Discharge / Q000706:statistics & numerical data; D062645:Percutaneous Coronary Intervention / Q000706:statistics & numerical data; D019990:Perioperative Care / Q000379:methods; D012189:Retrospective Studies; D019209:Troponin C / Q000097:blood*; D014481:United States / Q000453:epidemiology
chemical_list: D000925:Anticoagulants; D019209:Troponin C