title: [The importance of a normal ECG in non-ST elevation acute coronary syndromes].
abstract: BACKGROUND
  Admission ECG has a major impact on the diagnosis and management of non-ST elevation acute coronary syndromes (ACS).
  
  
  OBJECTIVE
  To assess the impact of the admission ECG on prognosis over non-ST ACS.
  
  
  METHODS
  prospective, continuous, observational study of 802 non-ST ACS patients from a single center.
  
  
  METHODS
  Patients were divided in 2 groups: A (n=538) - Abnormal ECG and B (n=264) - Normal ECG. Normal ECG was synonymous of sinus rhythm and no acute ischemic changes. A one-year clinical follow up was performed targeting all causes of mortality and the MACE rate.
  
  
  RESULTS
  Group A patients were older (68.7+/-11.7 vs. 63.4+/-12.7Y, p<0.001), had higher Killip classes and peak myocardial necrosis biomarkers. Furthermore, they had lower left ventricular ejection fraction (LVEF) (52.01+/-10.55 vs. 55.34+/- 9.51%, p<0.001), glomerular filtration rate, initial hemoglobin, and total cholesterol levels. Group B patients were more frequently submitted to invasive strategy (63.6 vs. 46.5%, p<0.001) and treated with aspirin, clopidogrel, beta blockers and statins. They also more often presented normal coronary anatomy (26.2 vs. 18.0%, p=0.45). There was a trend to higher in-hospital mortality in group A (4.6 vs. 1.9%, p=0.054). Kaplan-Meyer analysis showed that at one month and one year (95.1 vs. 89.5%, p=0.012) survival was higher in group B and the result remained significant on a Cox regression model (normal ECG HR 0.45 (0.21 - 0.97). There were no differences regarding the MACE rate.
  
  
  CONCLUSIONS
  In our non-ST elevation ACS population, a normal ECG was an early marker for good prognosis.
authors.affiliation: Cardiology Department, University Hospitals and Medical School, Coimbra, Portugal. rogeriopteixeira@gmail.com
authors.forename: Rogério
authors.initials: R
authors.lastname: Teixeira
authors.forename: Carolina
authors.initials: C
authors.lastname: Lourenço
authors.forename: Natália
authors.initials: N
authors.lastname: António
authors.forename: Sílvia
authors.initials: S
authors.lastname: Monteiro
authors.forename: Rui
authors.initials: R
authors.lastname: Baptista
authors.forename: Elisabete
authors.initials: E
authors.lastname: Jorge
authors.forename: Maria João
authors.initials: MJ
authors.lastname: Ferreira
authors.forename: Pedro
authors.initials: P
authors.lastname: Monteiro
authors.forename: Mário
authors.initials: M
authors.lastname: Freitas
authors.forename: Luís A
authors.initials: LA
authors.lastname: Providência
mesh_terms: D054058:Acute Coronary Syndrome / Q000175:diagnosis* / Q000401:mortality; D000368:Aged; D004562:Electrocardiography / Q000592:standards*; D004812:Epidemiologic Methods; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis