title: Etiologies and predictors of ST-segment elevation myocardial infarction.
abstract: OBJECTIVE
  Rapid diagnosis of ST-segment elevation myocardial infarction (STEMI) is essential for the appropriate management of patients. We investigated the prevalence, etiologies and predictors of false-positive diagnosis of STEMI and subsequent inappropriate catheterization laboratory activation in patients with presumptive diagnosis of STEMI.
  
  
  METHODS
  Four hundred fifty-five consecutive patients (62±13 years, 345 males) with presumptive diagnosis of STEMI between August 2008 and November 2010 were included.
  
  
  RESULTS
  A false-positive diagnosis of STEMI was made in 34 patients (7.5%) with no indication of coronary artery lesion. Common causes for the false-positive diagnosis were coronary spasm in 10 patients, left ventricular hypertrophy in 5 patients, myocarditis in 4 patients, early repolarization in 3 patients, and previous myocardial infarction and stress-induced cardiomyopathy in 2 patients each. In multivariate logistic regression analysis, symptom-to-door time >12 hours {odds ratio (OR) 4.995, 95% confidence interval (CI) 1.384-18.030, p=0.014}, presenting symptom other than chest pain (OR 7.709, 95% CI 1.255-39.922, p=0.027), absence of Q wave (OR 9.082, CI 2.631-31.351, p<0.001) and absence of reciprocal changes on electrocardiography (ECG) (OR 17.987, CI 5.295-61.106, p<0.001) were independent predictors of false-positive diagnosis of STEMI.
  
  
  CONCLUSIONS
  In patients whom STEMI was planned for primary coronary intervention, the false-positive diagnosis of STEMI was not rare. Correct interpretation of ECGs and consideration of ST-segment elevation in conditions other than STEMI may reduce inappropriate catheterization laboratory activation.
authors.affiliation: Department of Internal Medicine, Kyungpook National University Hospital, Daegu, Korea.
authors.forename: Myung Hwan
authors.initials: MH
authors.lastname: Bae
authors.forename: Sang Soo
authors.initials: SS
authors.lastname: Cheon
authors.forename: Joon Hyuk
authors.initials: JH
authors.lastname: Song
authors.forename: Se Yong
authors.initials: SY
authors.lastname: Jang
authors.forename: Won Suk
authors.initials: WS
authors.lastname: Choi
authors.forename: Kyun Hee
authors.initials: KH
authors.lastname: Kim
authors.forename: Sun Hee
authors.initials: SH
authors.lastname: Park
authors.forename: Jang Hoon
authors.initials: JH
authors.lastname: Lee
authors.forename: Dong Heon
authors.initials: DH
authors.lastname: Yang
authors.forename: Hun Sik
authors.initials: HS
authors.lastname: Park
authors.forename: Yongkeun
authors.initials: Y
authors.lastname: Cho
authors.forename: Shung Chull
authors.initials: SC
authors.lastname: Chae
keywords: False positive reactions; Myocardial infarction