title: Cardiac troponin T is an important predictor of mortality after cardiac surgery.
abstract: Serum troponin (cTnT) levels, a commonly measured biomarker of myocardial injury, has rarely been considered in risk models after cardiac surgery.
  
  
  
  Retrospective study of patients undergoing any cardiac surgery between 2004 and 2012. Patients with a history of recent myocardial injury (<21 days) were excluded. The minimum P value approach was used to determine categories of peak cTnT associated with in-hospital death. A multivariable analysis was performed to identify independent predictors of mortality.
  
  
  
  A total of 5318 patients without evidence of preoperative ischemia underwent a number of cardiac surgical interventions ranging from isolated coronary revascularization to combined valve coronary artery bypass grafting. The unadjusted in-hospital mortality rate was 3.3% (n = 175 patients). Four categories of peak cTnT were identified using the minimum P value approach: less than or equal to 0.6 ng/mL, 0.7 to 1.9 ng/mL, 2.0 to 3.1 ng/mL, and greater than 3.1 ng/mL with unadjusted mortality rates of 1.0%, 3.6%, 10.1%, and 33.1%, respectively. Multivariate logistic regression demonstrated that all peak cTnT levels greater than 0.6 ng/mL were independent predictors of in-hospital mortality in a dose-dependent manner.
  
  
  
  We demonstrate that in patients without preoperative myocardial ischemia, the demonstration of myocardial injury (>0.6 ng/mL) in the postoperative period is highly predictive of in-hospital death.
authors.affiliation: Department of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia.
authors.forename: Ahmed T
authors.initials: AT
authors.lastname: Mokhtar
authors.affiliation: Department of Surgery, Division of Cardiac Surgery, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: Jahanara
authors.initials: J
authors.lastname: Begum
authors.affiliation: Department of Surgery, Division of Cardiac Surgery, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Buth
authors.affiliation: Department of Surgery, Division of Cardiac Surgery, Dalhousie University, Halifax, Nova Scotia, Canada. Electronic address: jean.legare@nshealth.ca.
authors.forename: Jean-Francois
authors.initials: JF
authors.lastname: Legare
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood*; D001026:Coronary Artery Bypass / Q000401:mortality*; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000601:surgery*; D009674:Nova Scotia; D011183:Postoperative Complications / Q000097:blood / Q000401:mortality; D012189:Retrospective Studies; D020107:Troponin T / Q000097:blood*
chemical_list: D015415:Biomarkers; D020107:Troponin T
keywords: Cardiac surgery; Myocardial ischemia; Troponin