title: Diagnostic performance of initial salivary alpha-amylase activity for acute myocardial infarction in patients with acute chest pain.
abstract: BACKGROUND
  To rule out acute myocardial infarction (AMI) in chest pain patients constitutes a diagnostic challenge to emergency department (ED) physicians.
  
  
  OBJECTIVE
  To evaluate the diagnostic value of measuring salivary alpha-amylase (sAA) activity for detecting AMI in patients presenting to the ED with acute chest pain.
  
  
  METHODS
  sAA activity was measured in a prospective cohort of 473 consecutive adult patients within 4 h of onset of chest pain. Comparisons were made between patients with a final diagnosis of AMI and those with non-AMI. Univariate analysis and multiple logistic regression model were used to identify independent clinical predictors of AMI.
  
  
  RESULTS
  Initial sAA activity in the AMI group (n = 85; 266 ± 127.6 U/mL) was significantly higher than in the non-AMI group (n = 388; 130 ± 92.8 U/mL, p < 0.001). sAA activity levels were also significantly higher in patients with ST elevation AMI (n = 53) compared to in those with non-ST elevation AMI (n = 32) (300 ± 141.1 vs. 210 ± 74.1 U/mL, p < 0.001). The area under the receiver operating characteristic curve of sAA activity for predicting AMI in patients with acute chest pain was 0.826 (95% confidence interval [CI] 0.782-0.869), with diagnostic odds ratio 10.87 (95% CI 6.16-19.18). With a best cutoff value of 197.7 U/mL, the sAA activity revealed moderate sensitivity and specificity as an independent predictor of AMI (78.8% and 74.5%).
  
  
  CONCLUSIONS
  High initial sAA activity is an independent predictor of AMI in patients presenting to the ED with chest pain.
authors: Institute of Aerospace Medicine, School of Medicine, National Defense Medical Center, Taipei, Taiwan.
authors: Ying-Sheng
authors: YS
authors: Shen
authors: Wei-Lung
authors: WL
authors: Chen
authors: Hsin-Yu
authors: HY
authors: Chang
authors: Hung-Yi
authors: HY
authors: Kuo
authors: Yue-Cune
authors: YC
authors: Chang
authors: Hsin
authors: H
authors: Chu
mesh_terms: D000368:Aged; D019540:Area Under Curve; D015415:Biomarkers / Q000378:metabolism; D016022:Case-Control Studies; D002637:Chest Pain / Q000209:etiology; D016001:Confidence Intervals; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000175:diagnosis* / Q000201:enzymology*; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D012463:Saliva / Q000201:enzymology*; D055291:Salivary alpha-Amylases / Q000378:metabolism*; D018709:Statistics, Nonparametric; D019210:Troponin I / Q000097:blood
chemical_list: D015415:Biomarkers; D019210:Troponin I; D055291:Salivary alpha-Amylases