title: Serial changes in the high-frequency ECG during the first year following acute myocardial infarction.
abstract: BACKGROUND
  Previous studies have shown reduced high-frequency QRS components (HF-QRS) after acute myocardial infarction (MI). The purpose of this study was to investigate serial changes in HF-QRS during the first year following acute MI.
  
  
  METHODS
  A total of 75 patients were included. Standard- and high-frequency ECGs were recorded on five occasions during the year following the MI (a few days after the MI, after 6 weeks, and after 3, 6 and 12 months).
  
  
  RESULTS
  There was a statistically significant increase in HF-QRS during the follow-up year (P = 0.002). There were no significant differences in HF-QRS when comparing either the infarct location or the presence or absence of reperfusive therapy. Large differences in HF-QRS were observed, both intra-individually and inter-individually, during the year.
  
  
  CONCLUSIONS
  There was a statistically significant increase in HF-QRS during the year following acute MI.
authors.affiliation: Department of Clinical Physiology, Lund University, Lund, Sweden. elin.tragardh@med.lu.se
authors.forename: Elin
authors.initials: E
authors.lastname: Trägårdh
authors.forename: Olle
authors.initials: O
authors.lastname: Pahlm
authors.forename: Bo
authors.initials: B
authors.lastname: Hedén
authors.forename: Leif
authors.initials: L
authors.lastname: Sörnmo
authors.forename: Kristina
authors.initials: K
authors.lastname: Tägil
authors.forename: Galen S
authors.initials: GS
authors.lastname: Wagner
authors.forename: Jonas
authors.initials: J
authors.lastname: Pettersson
mesh_terms: D000368:Aged; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000628:therapy*; D015425:Myocardial Reperfusion; D012815:Signal Processing, Computer-Assisted; D013997:Time Factors