title: QRS duration: a novel marker of microvascular reperfusion as assessed by myocardial blush grade in ST elevation myocardial infarction patients undergoing a primary percutaneous intervention.
abstract: OBJECTIVE
  Prolonged QRS duration is a predictor of poor prognosis in patients with coronary artery disease. The association between the duration of QRS and myocardial reperfusion is not very well understood. Our aim was to assess the relationship between the measurements of QRS duration and myocardial blush grade (MBG) in patients with ST elevation myocardial infarction (STEMI) who were treated with a primary percutaneous intervention.
  
  
  METHODS
  A total of 213 patients (mean age: 57.5±11 years) with STEMI were included. ECG recordings were obtained for the evaluation of the QRS duration before and after primary percutaneous coronary intervention. Angiographic assessment in the infarct-related artery was performed using the MBG. Patients were categorized into two groups of those with impaired microvascular reperfusion (MBG: 0-1) and those with normal microvascular reperfusion (MBG: 2-3).
  
  
  RESULTS
  Overall, 105 and 108 patients had an MBG of 0-1 or 2-3, respectively. There is no significant difference between patient's characteristics. Despite the absence of a difference between two groups in terms of the QRS duration at presentation (P: 0.57), patients with impaired microvascular reperfusion were found to have longer QRS duration at immediately postprocedure (P: 0.003) and postprocedure 60 min time-points (P<0.001). Correlation analyses showed a positive correlation between pain-to-balloon time and QRS duration at postprocedure 60 min time-points (r: 0.137 and P: 0.04).
  
  
  CONCLUSIONS
  Our results suggest that longer QRS duration after angioplasty seemed to indicate the presence of impaired microvascular reperfusion in patients with STEMI.
authors.affiliation: Department of Cardiology, Gazi Yasargil Education and Research Hospital, Diyarbakir, Turkey.
authors.forename: Zülküf
authors.initials: Z
authors.lastname: Karahan
authors.forename: Barış
authors.initials: B
authors.lastname: Yaylak
authors.forename: Murat
authors.initials: M
authors.lastname: Uğurlu
authors.forename: İlyas
authors.initials: İ
authors.lastname: Kaya
authors.forename: Berzal
authors.initials: B
authors.lastname: Uçaman
authors.forename: Önder
authors.initials: Ö
authors.lastname: Öztürk
mesh_terms: D000368:Aged; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000503:physiopathology* / Q000628:therapy; D003326:Coronary Circulation; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008833:Microcirculation; D055806:Microvessels / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000628:therapy; D015425:Myocardial Reperfusion; D062645:Percutaneous Coronary Intervention; D011379:Prognosis; D013997:Time Factors