title: [Analysis of electrocardiographic recordings associated with acute myocardial infarction].
abstract: OBJECTIVE
  Evaluate correlations between variations in eletrocardiogram (ECG) recordings and acute myocardial infarction.
  
  
  METHODS
  Use of a low-cost software to digitalize printed and/or ".pdf" file format ECG recordings. Calculation of ST-segment area and amplitudes of the J and Y points.
  
  
  RESULTS
  The amplitude of the Y point holds maximum correlation with troponin concentration. ST-segment elevation is not a good statistical indicator of myocardial infarction severity. There is a strong negative correlation between the amplitude of the J point and the amount of magnesium ions, but no statistical correlation with sodium or calcium ions. Neither method for calculating the ST-segment area (pixel counts and interpolation) indicated any significant differences in the results.
  
  
  CONCLUSIONS
  The software used proved to be functional and cost-effective. Y point amplitude is a sensitive marker of myocardial infarction, and is also a calculation method both simpler to use and less subject to error than the calculation of the ST-segment elevation area.
authors.affiliation: Centro de Ensino Superior de Catalão, Catalão, GO, Brazil.
authors.forename: Paulo Henrique Garcia
authors.initials: PH
authors.lastname: Mansur
authors.forename: Lacordaire Kemel Pimenta
authors.initials: LK
authors.lastname: Cury
authors.forename: João Batista
authors.initials: JB
authors.lastname: Destro-Filho
authors.forename: Elmiro Santos
authors.initials: ES
authors.lastname: Resende
authors.forename: José Paulo Breda
authors.initials: JP
authors.lastname: Destro
authors.forename: Luana Michelli
authors.initials: LM
authors.lastname: de Oliveira
authors.forename: Diego Carvalho Gomes
authors.initials: DC
authors.lastname: de Moraes
authors.forename: Geraldo Rubens Ramos
authors.initials: GR
authors.lastname: de Freitas
authors.forename: Lucila Soares da Silva
authors.initials: LS
authors.lastname: Rocha
mesh_terms: D000704:Analysis of Variance; D004562:Electrocardiography / Q000191:economics / Q000379:methods / Q000592:standards*; D006801:Humans; D008955:Models, Cardiovascular; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000503:physiopathology / Q000517:prevention & control; D012815:Signal Processing, Computer-Assisted