title: Relation between fragmented QRS and collateral circulation in patients with chronic total occlusion without prior myocardial infarction.
abstract: OBJECTIVE
  It has been shown that the fragmented QRS (fQRS) on electrocardiogram (ECG) signifies regional myocardial scar in patients with non-Q-wave myocardial infarction (MI). We hypothesized that presence of fQRS on ECG may be related with poorly-grown collateral coronary circulation (CCC) in patients with chronic total coronary occlusion (CTO) without prior MI.
  
  
  METHODS
  This retrospective observational study is included 56 patients (mean age 61.73±7.96 years; 67.9% men) with CTO in one of the major coronary arteries. Collateral circulation was graded according to Rentrop's classification. The fQRS was defined as the presence of an additional R wave or notching of R or S wave or the presence of fragmentation in two contiguous ECG leads corresponding to a major coronary artery territory. Patients with pathological Q-wave or history of MI, typical bundle brunch blocks (BBB) and incomplete right BBB were excluded from study. Statistical analysis was performed using Chi-square test, Student's t-test and logistic regression analysis.
  
  
  RESULTS
  Fifteen patients had Rentrop grade 1, 15 patients had grade 2 and 26 patients had grade 3 CCC. Five (19%) of the patients who have grade 3 CCC, seven (47%) of the patients who had grade 2 CCC, ten (67%) of the patients who had grade 1 CCC had fQRS (p=0.002). Logistic regression analysis showed high predictive value of the presence of fQRS for Rentrop 1 CCC (OR=8.4, 95% CI 1.97-35.7; p=0.004).
  
  
  CONCLUSIONS
  Results of our study may implicate the presence of fQRS on electrocardiogram as a predictor of a poorly grown CCC in patients with chronic total occlusion without prior MI.
authors.affiliation: Department of Cardiology, Faculty of Medicine, Gaziosmanpaşa University, Tokat, Turkey. drhkadi@hotmail.com
authors.forename: Hasan
authors.initials: H
authors.lastname: Kadı
authors.forename: Köksal
authors.initials: K
authors.lastname: Ceyhan
authors.forename: Fatih
authors.initials: F
authors.lastname: Koç
authors.forename: Ataç
authors.initials: A
authors.lastname: Celik
authors.forename: Orhan
authors.initials: O
authors.lastname: Onalan
mesh_terms: D001145:Arrhythmias, Cardiac / Q000503:physiopathology*; D002908:Chronic Disease; D003097:Collateral Circulation / Q000502:physiology*; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000503:physiopathology*; D004562:Electrocardiography / Q000379:methods; D005260:Female; D006329:Heart Conduction System; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000503:physiopathology*; D012044:Regression Analysis; D012189:Retrospective Studies