title: Electrocardiographic prediction of lateral involvement in acute non-anterior wall myocardial infarction.
abstract: OBJECTIVE
  Recent research has established that a tall R-wave in V1 indicates lateral wall involvement in non-anterior wall myocardial infarction (MI). The objective of this study was to assess the value of the admission electrocardiogram (ECG) to predict R-waves and consequently lateral wall damage in the late phase of non-anterior MI.
  
  
  METHODS
  ECGs of 69 patients were analyzed. ST-segment changes in representative leads for lateral wall infarction such as V1, V2, V6 and I were correlated with the extent of QRS-wave changes in V1 and V6.
  
  
  RESULTS
  ST-segment elevation in V6 showed correlations with R/S ratio in V1 (r=0.802, B=0.440, P=<0.001) and with the depth of Q-waves in V6 (r=0.671, B=0.441, P=0.007). This correlation was higher in a small subgroup where the left circumflex branch (Cx) was the culprit vessel (r=0.888, B=1.469 and P=0.018). ST-segment depression in lead I correlated with the height of R and the surface of R in V1 (height times width of R) (r=0.542, B=-0.150, P=0.005 and r=0.538, B=-0.153, P=0.005 respectively), especially in the subgroup without proximal occlusions of RCA (r=0.711 and r=0.699). ST-segment depression in lead I also predicted Q-waves in V6 (r=0.538, B=0.114, P=0.006). ST-segment changes in V2 showed no significant correlation with either R- or Q-wave measurements.
  
  
  CONCLUSIONS
  ST-segment elevation in V6 in the acute phase of non-anterior MI predicts lateral involvement as expressed by the R/S ratio in V1 in the post reperfusion phase. A subgroup with Cx occlusion showed especially strong correlations, although the size of the group was small. In lead I ST-segment depression is correlated to height and surface of R in V1 and Q-waves in V6.
authors.affiliation: Department of Cardiology, Maastricht University Medical Center+, the Netherlands. Electronic address: S.Norda@student.maastrichtuniversity.nl.
authors.forename: Stephen
authors.initials: S
authors.lastname: Norda
authors.affiliation: Department of Cardiology, VU Medical Center Amsterdam, the Netherlands.
authors.forename: Kirian
authors.initials: K
authors.lastname: van der Weg
authors.affiliation: Department of Methodology and Statistics Maastricht University, the Netherlands.
authors.forename: Rein
authors.initials: R
authors.lastname: Vos
authors.affiliation: Department of Cardiology, Maastricht University Medical Center+, the Netherlands.
authors.forename: Anton P M
authors.initials: AP
authors.lastname: Gorgels
mesh_terms: D000465:Algorithms; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000175:diagnosis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018497:Ventricular Dysfunction, Right / Q000175:diagnosis* / Q000209:etiology
keywords: CMR; Electrocardiography; Infarct location; ST elevation myocardial infarction