title: Improving Prediction of Postoperative Myocardial Infarction With High-Sensitivity Cardiac Troponin T and NT-proBNP.
abstract: This study sought to determine whether preoperatively measured high-sensitivity cardiac troponin T (hs-cTnT) and N-terminal pro-brain natriuretic peptide (NT-proBNP) improve cardiac risk prediction in patients undergoing major noncardiac surgery compared with the standard risk indices.
  
  
  
  In this ancillary study to the Vitamins in Nitrous Oxide trial, patients were included who had preoperative hs-cTnT and NT-proBNP measured (n = 572). Study outcome was the incidence of postoperative myocardial infarction (MI) within the first 3 postoperative days. hs-cTnT was considered elevated if >14 ng/L and NT-proBNP if >300 ng/L. Additional cutoff values were investigated on the basis of receiver operating characteristic statistics. Biomarker risk prediction was compared with Lee's Revised Cardiac Risk Index (RCRI) with the use of standard methods and net reclassification index.
  
  
  
  The addition of hs-cTnT (>14 ng/L) and NT-proBNP (>300 ng/L) to RCRI significantly improved the prediction of postoperative MI (event rate 30/572 [5.2%], Area under the receiver operating characteristic curve increased from 0.590 to 0.716 with a 0.66 net reclassification index [95% confidence interval 0.32-0.99], P < .001). The use of 108 ng/L as a cutoff for NT-proBNP improved sensitivity compared with 300 ng/L (0.87 vs 0.53). Sensitivity, specificity, positive, and negative predictive value for hs-cTnT were 0.70, 0.60, 0.09, and 0.97 and for NT-proBNP were 0.53, 0.68, 0.08, and 0.96.
  
  
  
  The addition of cardiac biomarkers hs-cTnT and NT-proBNP to RCRI improves the prediction of adverse cardiac events in the immediate postoperative period after major noncardiac surgery. The high negative predictive value of preoperative hs-cTnT and NT-proBNP suggest usefulness as a "rule-out" test to confirm low risk of postoperative MI.
authors.affiliation: From the *Division of Clinical and Translational Research, Department of Anesthesiology, Washington University School of Medicine in St. Louis, St. Louis, Missouri; †Department of Internal Medicine, ‡Division of Biostatistics, §Cardiovascular Division, Department of Internal Medicine, and ‖Division of Core Clinical Laboratory Services, Department of Laboratory Medicine and Pathology, Mayo Clinic and Medical School, Rochester, Minnesota; ¶Department of Laboratory Medicine & Pathology, Hennepin County Medical Center, University of Minnesota School of Medicine, Minneapolis, Minnesota; and #Department of Pathology & Immunology (MGS), Mayo Clinic and Medical School, Rochester, Minnesota.
authors.forename: Michael
authors.initials: M
authors.lastname: Kopec
authors.forename: Andreas
authors.initials: A
authors.lastname: Duma
authors.forename: Mohammad A
authors.initials: MA
authors.lastname: Helwani
authors.forename: Jamie
authors.initials: J
authors.lastname: Brown
authors.forename: Frank
authors.initials: F
authors.lastname: Brown
authors.forename: Brian F
authors.initials: BF
authors.lastname: Gage
authors.forename: David W
authors.initials: DW
authors.lastname: Gibson
authors.forename: J Philip
authors.initials: JP
authors.lastname: Miller
authors.forename: Eric
authors.initials: E
authors.lastname: Novak
authors.forename: Allan S
authors.initials: AS
authors.lastname: Jaffe
authors.forename: Fred S
authors.initials: FS
authors.lastname: Apple
authors.forename: Mitchell G
authors.initials: MG
authors.lastname: Scott
authors.forename: Peter
authors.initials: P
authors.lastname: Nagele
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D015331:Cohort Studies; D004311:Double-Blind Method; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis*; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D011183:Postoperative Complications / Q000175:diagnosis*; D011237:Predictive Value of Tests; D012372:ROC Curve; D012016:Reference Values; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D020107:Troponin T / Q000097:blood*
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; D020107:Troponin T; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain