title: Perioperative myocardial necrosis in patients at high cardiovascular risk undergoing elective non-cardiac surgery.
abstract: OBJECTIVE
  Cardiovascular complications are important causes of morbidity and mortality in elective non-cardiac surgery. Although difficult to diagnose, perioperative myocardial infarction (MI) remains prognostically important. High-sensitivity troponin T (hs-TnT) assays allow detection of very minor damage to cardiac muscle. These assays are yet to be fully evaluated in the perioperative setting. Our aim was to determine the incidence and predictors of myocardial necrosis in patients at high cardiovascular risk undergoing elective non-cardiac surgery using hs-TnT.
  
  
  METHODS
  Prospective observational cohort study.
  
  
  METHODS
  352 consecutive patients undergoing elective major non-cardiac surgery prescribed antiplatelet therapy for primary or secondary cardiovascular event prevention.
  
  
  METHODS
  The incidence of elevated preoperative hs-TnT (≥14 ng/litre), hs-TnT-defined perioperative myocardial necrosis (≥ 14ng/litre and 50% increase from preoperative level), and perioperative MI were determined in relation to patient and surgical factors.
  
  
  RESULTS
  Preoperative hs-TnT was elevated in 31% and postoperative myocardial necrosis occurred in 22% of patients. Predictors of elevated baseline hs-TnT included age (OR 1.10, p<0.001), male gender (OR 2.91, p<0.001), diabetes requiring insulin therapy (OR 4.85, p=0.004) and chronic kidney disease (OR 3.60, p<0.001). Independent predictors of perioperative myocardial necrosis were age (OR 1.07, p<0.001), intraoperative hypotension (OR 3.67, p=0.001) and orthopaedic surgery (OR 2.46, p=0.005). Only 2% of patients suffered clinically apparent MI. Elevated preoperative hs-TnT did not predict perioperative myocardial necrosis or MI.
  
  
  CONCLUSIONS
  Perioperative myocardial damage occurs frequently in patients undergoing elective non-cardiac surgery, although the majority of events are clinically undetected. Age and intraoperative hypotension are independent predictors of myocardial necrosis in this setting.
authors.affiliation: Concord Repatriation General Hospital, Hospital Road, Concord, NSW 2139, Australia.
authors.forename: Richard F
authors.initials: RF
authors.lastname: Alcock
authors.forename: Dorothy
authors.initials: D
authors.lastname: Kouzios
authors.forename: Christopher
authors.initials: C
authors.lastname: Naoum
authors.forename: Graham S
authors.initials: GS
authors.lastname: Hillis
authors.forename: David B
authors.initials: DB
authors.lastname: Brieger
mesh_terms: D000368:Aged; D017558:Elective Surgical Procedures; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009203:Myocardial Infarction / Q000097:blood / Q000453:epidemiology* / Q000517:prevention & control; D009517:New South Wales / Q000453:epidemiology; D059035:Perioperative Period; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends; D020107:Troponin T / Q000097:blood
chemical_list: D010975:Platelet Aggregation Inhibitors; D020107:Troponin T