title: The Correlation between Infarct Size and the QRS Axis Change after Thrombolytic Therapy in ST Elevation Acute Myocardial Infarction.
abstract: OBJECTIVE
  Electrocardiography (ECG) may be a practical guiding tool for prognostic infarct sizing in ST elevation acute myocardial infarction (STEAMI). In this study, we sought to find a relation between the infarct size and the change in the QRS axis after thrombolytic therapy.
  
  
  METHODS
  Patients with STEAMI who received thrombolytic therapy were selected retrospectively. The mean QRS axes of two ECGs (before and 90 minutes after thrombolytic therapy) were calculated. Creatinine kinase MB (CKMB) was used as the marker of infarct size.
  
  
  RESULTS
  We did not detect any correlation between infarct size and change in the QRS axis with respect to any myocardial infarction MI localizations (p=0.80). However, in the isolated inferior MI group, there was a good correlation between CKMB and change in the QRS axis (r=-0.52 p=0.049).
  
  
  CONCLUSIONS
  The change in the QRS axis is rarely emphasized, providing a practical and promising tool for evaluating both the efficiency of the thrombolytic therapy and prognostic infarct sizing.
authors.affiliation: Department of Cardiology, Ataturk Education and Research Hospital, Ankara, Turkey.
authors.forename: M Fatih
authors.initials: MF
authors.lastname: Karakas
authors.affiliation: Department of Cardiology, Ataturk Education and Research Hospital, Ankara, Turkey.
authors.forename: Emine
authors.initials: E
authors.lastname: Bilen
authors.affiliation: Department of Cardiology, Facult of Medicine, Mustafa Kemal University, Hatay, Turkey.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Kurt
authors.affiliation: Department of Cardiology, Ataturk Education and Research Hospital, Ankara, Turkey.
authors.forename: Ugur
authors.initials: U
authors.lastname: Arslantas
authors.affiliation: Department of Cardiology, Ataturk Education and Research Hospital, Ankara, Turkey.
authors.forename: Gokturk
authors.initials: G
authors.lastname: Ipek
authors.affiliation: Department of Endocrinology, Facult of Medicine, Mustafa Kemal University, Hatay, Turkey.
authors.forename: Esra
authors.initials: E
authors.lastname: Karakas
authors.affiliation: Department of Cardiology, Ataturk Education and Research Hospital, Ankara, Turkey.
authors.forename: Isa Oner
authors.initials: IO
authors.lastname: Yuksel
authors.affiliation: Department of Cardiology, Ataturk Education and Research Hospital, Ankara, Turkey.
authors.forename: Ayse Saatcı
authors.initials: AS
authors.lastname: Yasar
authors.affiliation: Department of Cardiology, Ataturk Education and Research Hospital, Ankara, Turkey.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Bilge
keywords: Acute coronary syndrome; Acute myocardial infarction with ST elevation; Infarct size; QRS axis; Thrombolytic therapy